Technical field [0001]The present invention relates to a plated steel. BACKGROUND [0002]The construction materials, a wide variety of plating steel is utilized. And many, is a Zn-plated steel. From long life needs building materials, the study of high corrosion resistance of the Zn-plated steel has been made for a long time, various plating steel have been developed. High corrosion resistance plating steel for the first building material, in Zn-based plating layer, was added Al, with improved corrosion resistance, a Zn-5% Al-plated steel (GALFAN plated steel). To improve the corrosion resistance by adding Al in the plating layer is a well known fact, the plating layer with 5% Al added (specifically, Zn phase) Al phase formed improves the corrosion resistance in the. Zn-55% Al-1.6% Si -plated steel (Galvalume steel) The basically a plating steel with improved corrosion resistance for the same reason. 　Therefore, essentially planar portion corrosion resistance Al concentration is increased is improved. However, improvement of the Al concentration, causes a reduction in the sacrificial protection ability. [0003] 　Here, the charm of Zn-plated steel is a sacrificial protection effect to the base steel (steel). That is, the cut end surface of the plated steel material, the plated layer cracking unit during processing, and, in base iron (steel) bare portion which appears by peeling of the plating layer, the plating layer around before corrosion of the base steel (steel) is eluted plating eluted component to form a protective coating. Thus, it is possible to prevent red rust from base iron (steel) to some extent. [0004] 　This effect is generally has a low Al concentration, it Zn concentration is high is preferable. Therefore, high corrosion resistance of the plated steel material with a reduced Al concentration to a relatively low concentration of the order of 5% to 25% have been recently put to practical use. In particular, it is suppressing the Al concentration, further, plated steel containing Mg of about 1 to 3% have excellent planar portion corrosion resistance and sacrificial corrosion resistance than GALFAN plated steel. For this reason, become the market trend as plated steel, are widely known in the market today. As the plating steel to achieve high corrosion of containing the given amount of Al and Mg, for example, it has also been developed plated steel sheet disclosed in Patent Document 1 and Patent Document 2. [0005] 　The always construction materials for long life is desired, further improvement of the flat portion corrosion resistance and sacrificial corrosion resistance has been required, plating steel is most preferred that both both performance. Both of both performance today has been achieved mainly by alloying the plating layer due to the inclusion of Al and Mg. However, usually, the alloying of the plating layer causes an increase in the plating layer hardness, since also impair significantly workability than the plating layer of pure metal, it must be plated steel material with workability. The plating layer hardness for leading to wear resistance flop, it is preferable to effectively use the properties obtained by alloying of the plating layer. 　However, these flat portion corrosion resistance, sacrificial corrosion resistance, formability, and abrasion resistance of each performance, when both improving one, equal to other properties may be deteriorated, it is difficult properties to achieve both. [0006] 　For example, as described above, the selection of the concentration of Al in terms of the flat portion corrosion resistance is particularly important. And Al mainly as a plating steel took measures to impart a sacrificial corrosion protection, there are Al-Zn-based plated steel sheet as shown Al-plated steel sheet as described in Patent Document 3, and Patent Document 4. Further, on the other hand, it kept relatively low Al concentration of about 5% ~, as a plating steel imparted with flat portion corrosion resistance of these plated layer, Patent Document 5, Patent Document 6, Patent Document 7, and Patent Document 8 plated steel sheet shown is disclosed. [0007] Patent Document 1: Japanese Patent 2006-193791 JP Patent Document 2: WO 2011/001662 Patent Document 3: Japanese Patent 2002-012959 JP Patent Document 4: Japanese Patent 2015-214747 JP Patent Document 5: Japanese Patent 2001-115273 JP Patent Document 6: Japanese Patent 2001-316791 JP Patent Document 7: Japanese Patent 2010-275634 JP Patent Document 8: Japanese Patent 2001-64759 No. Summary of the Invention Problems that the Invention is to Solve [0008] 　However, the plating steel described in these Patent Documents 3-4, plating layer for the Al mainly, Zn amount is limited, the sacrificial protection effect and duration of its effect becomes extremely small. Therefore, despite the advantages of the flat portion corrosion resistance, it is hard to say that both the plane portion corrosion resistance and sacrificial corrosion resistance. As a result, the plated steel material, such as replace the Galvalume steel is not yet widespread in the market. 　The plating steel described in Patent Documents 5-8 also recently developed Zn-Al (5%) -Mg against (1%) based plating steel, flat portion corrosion resistance comparable to Al-based plated steel and of the grant, not been able to grant a further sacrifice corrosion resistance. Therefore, it is hard to say that attractive performance grant is made to an existing Zn-Al-Mg plated steel. 　Then, any of plating steel also hard to say that there has been implemented both in processability and abrasion resistance. [0009] 　One aspect of the object of the present disclosure, together with improvement of the flat portion corrosion resistance and sacrificial corrosion resistance and to provide a plating steel having both workability and abrasion resistance. Means for Solving the Problems [0010] 　It means for solving the problems include the following aspects. [0011] <1> 　and steel, a plated steel material with a plated layer containing Zn-Al-Mg alloy layer disposed on the surface of the steel product, 　the Zn-Al-Mg alloy layer has a Zn phase, and said containing Mg-Sn intermetallic compound phase Zn phase, 　the plating layer is, in 　mass%, Zn: 65.0% 　greater, Al: 5.0% ultra-than 　25.0%, Mg: 3.0% ultra-less% 　12.5, Sn: 　0.1% ~ 20.0%, Bi: less than% ~ 5.0 　0%, an In: less than% ~ 2.0 0%, 　Ca: 0% 　3.00% ~, Y: 　0% ~ 0.5%, La: less than% ~ 0.5 　0%, Ce: less than% ~ 0.5 　0%, Si: less than% ~ 2.5 　0%, Cr : less than% ~ 0.25 　0%, Ti: less than% ~ 0.25 　0%, Ni: less than% ~ 0.25 　0%, Co: less than% ~ 0.25 　0%, V: 0% ~ 0. less than 25%, 　Nb: less than to 0.25 　0%% Cu: less than to 0.25 　0%% Mn: less than 0% to 0.25%, 　Fe: 　0% ~ 5.0%, Sr: less than% ~ 0.5 　0%, Sb: less than% ~ 0.5 　0%, Pb: less than% ~ 0.5 　0%, B: 0% ~ 0. less than 5%, and 　consists of impurities, and plated steel having a chemical composition satisfying the following formulas 1 through equation 5. 　Formula 1: Bi + In 　The average crystal grain size of the Mg-Sn intermetallic compound phase, plating steel according to less than 1 [mu] m <1>. <3> 　In the above cross-section of the Zn-Al-Mg alloy layer, the area fraction of Mg-Sn intermetallic compound phase of less than the crystal grain size 1μm for Zn phase containing Mg-Sn intermetallic compound phase, 10-50 % a is <1> or plating steel according to <2>. <4> 　In the cross section of the Zn-Al-Mg alloy layer, Zn phase containing the Mg-Sn intermetallic phase is present at least 3% in area fraction for a cross section of the Zn-Al-Mg alloy layer <1> - plated steel material according to any one of <3>. <5> 　using Cu-K [alpha rays, X-ray output was measured under the conditions a 40kV and 150 mA, the X-ray diffraction pattern of the plating layer surface, specific strength I (Mg-Sn intermetallic compound phase) = { I (22.8 ° intensity (cps)) + I (23.3 ° intensity (cps)) + I (24.2 ° intensity (cps))} / 3 × I ( background intensity at 20 ° (cps)) is less than 1.5 <1> - plated steel material according to any one of <4>. <6> 　In the plating layer is from 0.05 to 3.00% the content of Ca is in mass%, and as the Mg-Sn intermetallic compound phase, MgCaSn phase and Mg in the Zn phase 9 Sn 5 has a 　phase, using a Cu-K [alpha rays, X-ray output was measured under the conditions a 40kV and 150 mA, the X-ray diffraction pattern of the plating layer surface, specific strength I (MgCaSn + Mg 9 Sn 5 ) = {I (22.8 ° intensity (cps)) + I (26.3 ° intensity (cps))} / I ( 23.3 ° intensity (cps)) is less than 0.3, and I (23.3 ° strength (cps)) is equal to or greater than 500cps <1> ~ <5> plated steel material according to any one of. <7> 　In the plating layer, 4.0% Ultra-than 12.5% content of Mg is in mass%, 0.05 to 3.00% the content of Ca is in mass%, content of Si the amount is 0.01 to 2.5% by mass%, 　Using Cu-K [alpha rays, X-ray output was measured under the conditions a 40kV and 150 mA, the X-ray diffraction pattern of the plating layer surface, among the diffraction peaks appearing at 23.0 ~ 23.46 °, the strongest intensity plated steel according to the diffraction peak appears between 23.36 ~ 23.46 ° <5> of. <8> 　In the plating layer, from 0.05 to 3.00% the content of Ca is in mass%, and 0.01 to 2.5% Si content in mass%, 　the Zn-Al- Mg alloy layer, contains at least one selected from average crystal grain size 1μm or more Ca-Al-Si intermetallic compound phase and an average grain diameter 1μm or more Mg-Al-Si intermetallic group consisting compound phase to <1> - plated steel material according to any one of <7>. <9> 　In the plating layer, the content of Ca is 0.05 to 3.00% in mass%, 　the in the cross section of the Zn-Al-Mg alloy layer, the above grain size 1 [mu] m Ca-Zn-Al intermetallic phase, present more than 5% in area fraction for a cross section of the Zn-Al-Mg alloy layer <1> to <8> any one the plating steel according to. <10> 　In the plating layer, from 3.00 to 20.00% the Sn content in mass%, and, when the contents of the elements of each of Sn and Zn, wherein: 0.05 ~ any one of <9>. <11> 　In the cross section of the Zn-Al-Mg alloy layer, Zn phase and eutectoid tissue below configured lamellar spacing 300nm of Al phase is present more than 10% area fraction for the cross section of the Zn-Al-Mg alloy layer <1> - plated steel material according to any one of <10>. <12> 　In the cross section of the Zn-Al-Mg alloy layer, Zn-Al-MgZn 2 ternary eutectic structure area fraction of a 0-5% <1> to any one of <11> plated steel described. <13> 　In the plating layer, the content of the Sn is less than 0.10 to 3.00% in mass% <1> to <9> plated steel material according to any one of. <14> 　the plating layer, the plating steel according to any one of <1> to <13> with Al-Fe alloy layer between the steel and the Zn-Al-Mg alloy layer. The invention's effect [0012] 　One aspect of the object of the present disclosure, together with improvement of the flat portion corrosion resistance and sacrificial corrosion resistance, plating steel having both workability and wear resistance is provided. BRIEF DESCRIPTION OF THE DRAWINGS [0013] [1] is an example of a ternary eutectic structure in the existing Zn-Al-Mg plated layer (Zn-11% Al-3 % Mg-0.2% Si). [2] is a SEM reflection electron image of an example of the plating layer of the present disclosure. Is a SEM reflection electron image showing an enlarged image of the Zn phase portion of FIG. 3 FIG. It is a SEM reflection electron image showing another example of the plating layer in FIG. 4 this disclosure. 5 is a SEM reflection electron image showing an enlarged view of the periphery of the Mg-Sn intermetallic compound phase of massive FIG. 6 is a SEM reflection electron image showing another example of the plating layer of the present disclosure. 7 is a SEM reflection electron image showing an enlarged image of the Zn phase and eutectoid tissue below configured lamellar spacing 300nm of Al phase of FIG. 6 (Zn-Al fine eutectoid tissue). It is a SEM reflection electron image showing another example of the plating layer in FIG. 8 the invention. In [9] FIG. 8 is an enlarged image of the plating tissue in the frame (SEM reflection electron image). A [10] enlarged image of the vicinity of Fe interface of the plating layer shown in FIG. 8 (TEM images). In FIG 11A] FIG. 10 is an electron diffraction image of the irregular intermetallic phase (13). In FIG 11B] FIG. 10 is a EDS spectra of amorphous intermetallic phase (13). In FIG 12A] FIG. 10 is an electron diffraction image of the needle-like intermetallic compound phase (14). In FIG 12B] FIG. 10 is a EDS analysis spectrum of the needle-like intermetallic compound phase (14). [Figure 13] Zn phase and eutectoid tissue below configured lamellar spacing 300nm of Al phase SEM reflection electron image for explaining a method of measuring the determination and area fraction of (Zn-Al fine eutectoid tissue) is there. [Figure 14] Zn-Al-MgZn 2 is a SEM reflection electron image for explaining a method of measuring the determination and the area fraction of the ternary eutectic structure. DESCRIPTION OF THE INVENTION [0014] 　Hereinafter, an example of the present disclosure. 　In the present disclosure, the content of each element in the chemical composition shown in the "%" means "% by mass". 　Further, the numerical range expressed using "to" means a range including numerical values described before and after "to" as the lower and upper limits. 　Further, numerical ranges when the numerical values set forth are "super" or "less than" are assigned before and after "to" means a range that does not include the lower limit or the upper limit value of these values. 　The content of elements in chemical composition, element content (e.g., Zn amount, Mg content, etc.) or elemental concentrations (e.g., Zn concentration, Mg concentration, etc.) may be referred to. 　Also, the term "process" not only separate steps, even if that can not be clearly distinguished from other processes intended purpose of the process if it is achieved, are included in this term. 　In addition, the "planar portion corrosion resistance", (specifically Zn-Al-Mg alloy layer) plating layer shows a corrosion hardly nature itself. 　Further, the "sacrificial protection property", base iron (steel) bare portion (e.g. the cut end surface of the plated steel material, the plated layer cracking unit during processing, and the peeling of the plating layer, locations base iron (steel) is exposed ) indicating the property of inhibiting corrosion of. [0015] 　Plated steel of the present disclosure, a steel, is disposed on the surface of the steel material, a hot dip plated steel sheet having a plating layer containing Zn-Al-Mg alloy layer, a Zn-Al-Mg alloy layer is Zn phase a, and the containing Mg-Sn intermetallic compound phase Zn phase, plating layer has a predetermined chemical composition. [0016] 　Plated steel of the present disclosure, the above-described configuration, the improvement of the flat portion corrosion resistance and sacrificial corrosion resistance, achieving both workability and abrasion resistance. Plated steel of the present disclosure has been found by the following findings. [0017] 　The present inventors have for the various performances of the plating layer of Zn-Al-Mg plated steel, and obtained the following findings. 　To obtain the recent most highly corrosion resistant Zn-Al-Mg plated steel sheet the same level or more of the planar portion corrosion resistance, Al concentration is minimal than 5%, Mg concentration is 3% Ultra necessary. If falls below these concentrations, can not be both planar portion corrosion resistance and sacrificial corrosion resistance with respect to existing Zn-Al-Mg plated steel sheet. 　On the other hand, application of sacrificial protection of the plating layer, in addition to the control of the Al concentration and Mg concentration, a certain amount is contained Sn in the plating layer, the plating layer (specifically, Zn-Al-Mg alloy layer) It can be realized by bringing a change in the configuration phase. Specifically, mainly the Zn phase which are formed on the Zn-Al-Mg alloy layer, by precipitating Mg-Sn intermetallic compound phase, conventionally, could not be obtained in the molten Zn-plated steel level sacrifice corrosion resistance is the expression of. 　When the Mg-Sn intermetallic compound phase is contained in the Zn phase, but increases the hardness processability of Zn phase it is not degraded. Additionally, Zn, Al, by appropriately controlling the respective concentrations of Mg and Sn, while the chemical composition of the plating layer is high alloy composition, the conventional Zn-Al-Mg plated steel equivalent processability maintain, and superior in wear resistance to maintain high plating layer hardness by highly alloyed chemical composition of the plating layer. [0018] 　From the above, the plated steel sheet of the present disclosure, together with improvement of the flat portion corrosion resistance and sacrificial corrosion resistance, it has been found that a plated steel material having both workability and abrasion resistance. 　Then, in particular, plating steel of the present disclosure is excellent in sacrificial protection property is improved cut end face corrosion resistance. [0019] 　Here, Mg-Sn intermetallic compound phase (hereinafter, referred to as a convenience to Mg-Sn intermetallic compound phase "fine MCSB phase") includes an intermetallic compound phase corresponding to the following (1) to (5) . Incidentally, Mg-Sn intermetallic compound phase may be interstitial solid solution elements such as Si. 　(1) Mg 2 Sn phase 　(2) Mg 9 Sn 5 phase 　(3) Bi in a part of the Sn, In, Cr, Ti, Ni, Co, V, Nb, Cu, and at least one of Mn was substituted substituted Mg 2 Sn phase and Mg 9 Sn 5 phase (Mg 2 Sn phase and Mg 9 Sn 5 phase of substitution of the 　phase) Ca, Y, at least one of La and Ce is substituted in part of (4) Mg substituted Mg 2 Sn phase and Mg 9 Sn 5 phase (Mg 2 Sn phase and Mg 9 Sn 5 　phase) substitution of Ca to a portion of (5) Mg, Y, and at least one substitution of La and Ce, and Bi in a part of the Sn, In, Cr, Ti, Ni, Co, V, nb, Cu, and at least one is substituted with substituted Mg of Mn 2 Sn phase and Mg 9 Sn 5 phase (Mg 2 Sn phase and Mg 9 Sn 5 substituents phases) 　it should be noted that these Mg 2 Sn phase and Mg 9 Sn 5 phase of substituents of the "Mg 2 may be collectively referred to as phase substitution of Sn. [0020] 　The following is a detailed explanation of the plating steel of the present disclosure. [0021] 　For steel to be plated will be described. 　The shape of the steel is not particularly limited, steel, other steel plate, steel pipe, civil engineering materials (Sakumizo, corrugated pipes, drainage ditch lid, Hisuna prevention plate, bolts, wire mesh, guardrail, cut-off wall, etc.) , household members (housing of the air conditioner outdoor unit, etc.), automobile parts (suspension member or the like), and a molded processed steel. Molding, for example, pressing, roll forming, various plastic working techniques such as bending can be utilized. [0022] 　The material of the steel is not particularly limited. Steel, for example, generally steel, Ni pre-plating steel, Al-killed steel, very low carbon steel, high carbon steel, various high strength steels, a part of high-alloy steels (Ni, strengthening such as Cr element-containing steel) such as various steel is applicable. 　Steel, the method of manufacturing the steel, the production method of the steel sheet (hot rolling process, pickling process, cold-rolled process, etc.) for also conditions such as, but is not particularly limited. 　Steel may be a pre-plated steel which is pre-plated. [0023] 　Next, a description will be given of a plating layer. 　Plating layer comprises a Zn-Al-Mg alloy layer. Plating layer, in addition to the Zn-Al-Mg alloy layer may include Al-Fe alloy layer. Al-Fe alloy layer has between the steel and the Zn-Al-Mg alloy layer. [0024] 　That is, the plating layer may be a single-layer structure of Zn-Al-Mg alloy layer may have a laminated structure including a Zn-Al-Mg alloy layer and the Al-Fe alloy layer. For the laminated structure, Zn-Al-Mg alloy layer may be a layer constituting the surface of the plating layer. 　However, although the oxide film of the plated layer constituent elements on the surface of the plating layer is formed to a thickness of about 50 nm, the thickness of the thickness of the entire plating layer is regarded as not constituting a main body of the thin plated layer. [0025] 　The thickness of the Zn-Al-Mg alloy layer is, for example, 2μm or more 95μm or less (preferably 5μm or 75μm or less). [0026] 　On the other hand, the thickness of the entire plating layer is, for example, lower than about 100 [mu] m. Since the plating layer total thickness depends on plating conditions, there is no particular limitation on the upper limit and the lower limit of the plating layer total thickness. For example, the thickness of the entire plating layer is in the conventional melt plating related viscosity and specific gravity of the plating bath. Furthermore the drawing speed and the wiping of the strength of the steel sheet (plating original plate), the plating amount is basis weight adjusted. Therefore, the lower limit of the plating layer total thickness can be considered to be about 2 [mu] m. 　On the other hand, by the weight and uniformity of the plated metal can be fabricated by melt plating, the thickness of the plating layer is about 95 .mu.m. 　By drawing speed and the wiping condition from the plating bath, since the thickness of the plating layer can be freely, forming a plating layer having a thickness of 2 ~ 95 .mu.m is not particularly difficult to manufacture. [0027] 　It will now be described Al-Fe alloy layer. [0028] 　Al-Fe alloy layer (specifically, between the steel and the Zn-Al-Mg alloy layer) the surface of the steel material is formed on, Al as a tissue 5 Fe phase is a layer of the main phase. Al-Fe alloy layer is formed by mutual atomic diffusion base iron (steel) and the plating bath. When using the hot-dip plating method as method, a plating layer containing Al element, easy to Al-Fe alloy layer is formed. Certain concentration or more Al in the plating bath because it is contained. Al 5 Fe phase is most forms. However, the atomic diffusion takes time, and in a portion near the base steel, there is also a portion where the Fe concentration is high. Therefore, AlFe alloy layer, in part, AlFe phase, Al 3 Fe phase, Al 5 Fe 2 in some cases and phase contains minor amounts. Furthermore, since the Zn also included a constant concentration in the plating bath, the Al-Fe alloy layer, Zn also contain minor amounts. [0029] 　In the corrosion resistance, Al 5 Fe phase, Al 3 Fe phase, AlFe phase, and Al 5 Fe 2 is not much different be any phase of phase. The corrosion resistance referred to herein is a corrosion resistance in a portion not affected by the welding. Occupied plating layer, the thickness of the Al-Fe alloy layer is small, and because low corrosion resistance compared to Zn-Al-Mg alloy layer, the corrosion resistance in the whole, much difference between the proportion of these phases is replaced there is no. [0030] 　Here, if containing Si in the plating layer, Si is particularly easily incorporated into Al-Fe alloy layer, it may become Al-Fe-Si intermetallic compound phase. The intermetallic compound phase are identified, there is AlFeSi phase, isomers, alpha, beta, q1, q2-AlFeSi equality exists. Therefore, Al-Fe alloy layer is sometimes they AlFeSi equality is detected. The Al-Fe alloy layer containing these AlFeSi equality also referred to as Al-Fe-Si alloy layer. 　Incidentally, with respect to Al-Fe-Si alloy layer also Zn-Al-Mg alloy layer, since the thickness is small, the effect in the corrosion resistance in the entire plating layer small. [0031] 　Further, when using various pre-plated steel material plated raw material (such as be plated), the amount of deposition of the pre-plating, the structure of Al-Fe alloy layer may vary. Specifically, around Al-Fe alloy layer, if pure metal layer used for the pre-plating remains, Zn-Al-Mg alloy layer component intermetallic compound phase preplating component is bonded (e.g., Al 3 If Ni equality) to form an alloy layer, if Al-Fe alloy layer partially substituted Al atoms and Fe atoms form, or, Al atoms. And the like when a part of Fe atoms and Si atoms to form a Al-Fe-Si alloy layer was replaced. In any case, for these alloy layers also Zn-Al-Mg alloy layer, since the thickness is small, a small influence in the corrosion resistance in the entire plating layer. [0032] 　In other words, the Al-Fe alloy layer, Al 5 besides the alloy layer composed mainly of Fe phase, a layer comprising an alloy layer of the various embodiments. [0033] 　The thickness of the Al-Fe alloy layer is, for example, more than 0 .mu.m 5 [mu] m or less (typically, 100 nm or 5 [mu] m or less). 　That, Al-Fe alloy layer may not be formed. However, usually, to form a plating layer by hot dipping in a plating composition defined in the present disclosure, between the steel and the Zn-Al-Mg alloy layer, 100 nm or more Al-Fe alloy layer is formed. The thickness lower limit of the Al-Fe alloy layer is not intended to particularly limit, in forming the molten plating layer containing Al has been found to inevitably Al-Fe alloy layer is formed . Then, a thickness of the case of forming the empirically 100nm before and after the most Al-Fe alloy layer is suppressed, and is determined to a thickness to sufficiently secure adhesion between the plated layer and the base steel (steel). Since there is Al concentration is high unless taken special means, in the hot dipping method, it is difficult to form a thin Al-Fe alloy layer than 100 nm. However, even if the thickness of the Al-Fe alloy layer and be less than 100 nm, also, Al-Fe alloy layer is not necessarily formed, great influence is presumed to not give the plating performance. [0034] 　On the other hand, when the thickness of the Al-Fe alloy layer is greater than or equal to 5 [mu] m, Al component is insufficient for Zn-Al-Mg alloy layer formed on the Al-Fe alloy layer further adhesion of the plating layer, workability there is a tendency that is extremely deteriorated. Therefore, the thickness of the Al-Fe alloy layer is limited to 5μm or less. 　Incidentally, Al-Fe alloy layer is closely related with regard Al concentration and the Sn concentration, it generally Al concentration and the Sn concentration is high, in the growth rate faster trend. [0035] 　Al-Fe alloy layer is Al 5 because often Fe phase is the main structure, the chemical composition of the Al-Fe alloy layer, Fe: 25 ~ 35%, Al: 65 ~ 75%, Zn: 5% or less, and balance: composition containing impurities can be exemplified. [0036] 　Usually, contribution since it towards the thickness of the Zn-Al-Mg alloy layer than Al-Fe alloy layer is thick is normally, to the plane portion corrosion resistance of a plated steel sheet Al-Fe alloy layer, Zn- small compared to the al-Mg alloy layer. However, the Al-Fe alloy layer contains Al and Zn is a corrosion resistant element to be inferred from component analysis results certain concentration or more. Therefore, Al-Fe alloy layer has a corrosion barrier effect and some sacrificial capacity for the base steel (steel). [0037] 　Here, it is difficult to verify the sole corrosion resistance contribution of small thickness Al-Fe alloy layer in a quantitative measurement. However, for example, when there is a sufficient thickness to Al-Fe alloy layer, a Zn-Al-Mg alloy layer on the Al-Fe alloy layer precisely removed by cutting from the surface of the plating layer in end milling or the like, corrosion test by applying, evaluating a single corrosion resistance of Al-Fe alloy layer it is possible. Al-Fe alloy layer, because it contains Al component and a small amount of Zn component, if having a Al-Fe alloy layer, red rust occurred in dots, not have the Al-Fe alloy layer, the base steel ( as at the time of steel) bare, not over the entire surface rust. [0038] 　Also, during the corrosion test, when carried observing a section of the plating layer that led up to red rust immediately before the base steel (steel), Al-Fe alloy layer be an upper layer of Zn-Al-Mg alloy layer is eluted and Sabika only There remains, it can be confirmed that by corrosion of the base iron (steel). This electrochemically, but Al-Fe alloy layer is more noble than Zn-Al-Mg layer, in order to position the negative than the base steel (steel). For these reasons, also Al-Fe alloy layer can be determined to have a certain corrosion resistance. [0039] 　From the viewpoint of corrosion, Al-Fe alloy layer has the effect of delayed thicker preferably red rust time if thicker. However, a thick Al-Fe alloy layer because causes significantly degrade the plating workability, the thickness is preferably less than a certain thickness. From the viewpoint of workability and suitable thickness is found, Al-Fe alloy layer is preferably 5μm or less, V bending cracks generated starting from the plating Al-Fe alloy layer generated in the test or the like, powdering amount There is reduced. Still more preferably 2μm or less. [0040] 　Next, a description will be given chemical composition of the plating layer. 　Composition of Zn-Al-Mg alloy layer contained in the plating layer, the component composition ratio of the plating bath is substantially maintained also in Zn-Al-Mg alloy layer. In the melt plating, Al-Fe for the formation of the alloy layer to react in the plating bath has been completed, Al component of the Zn-Al-Mg alloy layer by Al-Fe alloy layer formed, reduction in Zn ingredient is usually it is slight. [0041] 　Then, the improvement of the flat portion corrosion resistance and sacrificial corrosion resistance, in order to achieve both workability and abrasion resistance, the chemical composition of the plating layer, is as follows. 　In particular, as in the following chemical composition plating layer, in exceeding the Zn concentration 65.0%, Mg and Sn By including a predetermined amount, leap sacrificial anti-corrosion Zn phase having the Zn-Al-Mg alloy layer to enhanced, with high sacrificial corrosion resistance, high flat portion corrosion resistance of Al can be acquired. Then, it acquires also the processability and abrasion resistance. [0042] 　In other words, the chemical composition of the plating layer, by 　mass%, Zn: 65.0% 　greater, Al: 5.0% ultra-than 　25.0%, Mg: 3.0% ultra-than 　12.5%, Sn : 　0.1% ~ 20.0%, Bi: less than% ~ 5.0 　0%, an In: less than% ~ 2.0 　0%, Ca: 0% ~ 　3.00%, Y: 0% ~ 0. 　5%, La: less than% ~ 0.5 0%, 　Ce: less than% ~ 0.5 　0%, Si: less than% ~ 2.5 　0%, Cr: less than% ~ 0.25 　0%, Ti: 0 % ~ less than 　0.25%, Ni: less than 0% - 　0.25%, Co: less than 0% ~ 　0.25%, V: less than% 0.25 　0%, Nb: 0% - 0.25% 　less, Cu: less than% ~ 0.25 　0%, Mn: less than% ~ 0.25 　0%, Fe: 　0% ~ 5.0%, Sr: less than% ~ 0.5 　0%, Sb: 0% ~ less than 　0.5%, Pb: less than 0% to 0.5% , 　B: less than 0% to 0.5%, and 　the made chemical composition from the impurity. [0043] 　However, the chemical composition of the plating layer, satisfies the following formula 1 through Equation 5. 　Formula 1: Bi + In Zn, in addition to the planar portion corrosion resistance, an element necessary for obtaining the sacrificial protection property. Zn concentration, in consideration with the atomic composition ratio, Al, since it is the plating layer formed with low density of the elements Mg, etc., it is necessary to Zn mainly in atomic composition ratio. 　If the Zn concentration is less than 65.0%, Al phase is constituted by a principal to Zn-Al-Mg alloy layer, Zn phase to ensure the sacrificial corrosion resistance is insufficient. Further, when the Al phase increases, Al is because they tend to solid solution a wide variety of elements compared to Zn, it changes the type of constituent phases of the plating layer. Furthermore, it can not be maintained the structure of the distribution of the intermetallic compound phase of interest. 　Thus, Zn concentration is 65.0 percent. Zn concentration is preferably 70% or more. The upper limit of the Zn concentration is the concentration at which the balance other than the elements and impurities except Zn. [0049] Al is a plating layer (in particular, Zn-Al-Mg layer) is an element necessary to contain other elements other than Zn into. Originally, the Zn plating layer (Zn layer), another element is difficult to contain, for example, can not be added Mg, Ca, an element such as Si at a high concentration. However, the Zn plating layer (Zn layer), that Al is contained, containing these elements, it is possible to produce a Zn-Al-Mg alloy layer. [0050] 　Al, in addition to forming the Al phase to impart a planar portion corrosion resistance and plastic deformability, contribute to the formation of the Al-Fe alloy layer, in order to ensure the adhesion, is an essential element. [0051] 　Al concentration is 5.0% or less is, Mg, other Ca, tend to contain the more difficult the alloying elements imparting performance to the plating layer. Further, Al is the density is low, compared to Zn, relative to the content of mass, many phases of Al phase forming. However, Al concentration is 5.0% or less, there is a tendency that most of the Zn-Al-Mg alloy layer is Zn phase. Thereby, it leads to that the flat portion corrosion resistance decreases significantly. In Zn-Al-Mg alloy layer, the Zn phase is a first phase is not preferable from the viewpoint of corrosion resistance. As described later, if the Zn phase is a first phase, poor Zn-Al-MgZn the flat surface portion corrosion resistance and workability 2 ternary eutectic structure is easily produced, and tendency to planar portion corrosion resistance and workability are degraded Become. [0052] 　Further, the Al concentration is 5.0% or less, the Zn-Al-Mg alloy layer, poor MgZn of plastic deformability 2 coarsely be easily grown phase becomes the primary crystal is significantly workability of the plating layer in the worse trend. [0053] 　Therefore, the lower limit of the Al concentration, and greater than 5.0% (preferably 10.0% or higher). [0054] 　On the other hand, when the Al concentration increases, Zn-Al-Mg alloy layer rapidly increasing proportion of Al phase, Zn phase and MgZn required sacrificial imparting 2 reduces the proportion of the phases. Therefore, to improve the planar portion corrosion resistance and workability. 　However, closer to the configuration sacrificial protection is lost. Further, when the Al concentration is excessively increased, as described above, a wide variety of elements will be incorporated into the Al phase, Zn phase is not formed containing fine MCSB phase. When forming a plating layer by hot dipping process, tends to thickness of Al-Fe alloy layer becomes thick. Thereby, a large amount of Mg and Zn is contained in Al phase, very poor Al phase corrosion resistance and plastic deformability resulting in formation. Such formation of the Al phase is not preferable in terms of workability ensured. [0055] 　Therefore, the upper limit of the Al concentration is less than 25.0% (preferably less 23.0%). [0056] Mg is an element necessary in order to impart a sacrificial corrosion resistance. Moreover, Mg is an element necessary for forming a fine MCSB phase in Zn phase. Usually, when Mg is contained in the Zn-Al-Mg alloy layer, MgZn having sacrificial corrosion resistance 2 to form a phase. However, MgZn 2 phase, as fine MCSB phase, the sacrificial corrosion protection is not high, also is extremely brittle intermetallic phases. Therefore, MgZn 2 is preferably phase is small. [0057] 　Mg concentration is 3.0% or less, the intermetallic compound phase required planar portion corrosion resistance and sacrificial protection granted (fine MCSB phase, MgZn 2 can not form phase) with sufficient quantity. Furthermore, since the Zn Airyo increases, Zn phase becomes the first phase Zn-Al-MgZn 2 because the ratio of the ternary eutectic structure increases, workability is not preferable from the viewpoint of corrosion resistance. [0058] 　Therefore, the lower limit of the Mg concentration is 3.0 percent. 　In view of the formation of fine MCSB phase, Mg concentration is high enough it is preferable, from the specific gravity calculations, in more than one third of the concentration of Sn concentration, Mg good to be contained. Further, from the viewpoint of the planar portion corrosion resistance and sacrificial corrosion resistance, at least 1/3 of the concentration of Sn concentration, Mg good to be contained. Therefore, the lower limit of the Mg concentration is 5.0 percent are preferred. [0059] 　On the other hand, the Mg concentration is 12.5% or more, MgZn 2 increased rapidly Airyo phase, the plastic deformability of the Zn-Al-Mg alloy layer is lost, the workability is deteriorated. [0060] 　Therefore, the upper limit of the Mg concentration is less than 12.5% ​​(preferably 10.0% or less). [0061] Sn is contained in Zn phase, it is an element necessary for forming fine MCSB phase to impart high sacrificial corrosion resistance. 　Here, Sn, Bi and In, the Al and Zn in the plating bath without forming intermetallic phases, always combines with Mg to form an intermetallic compound phase. Specifically, Sn, when obtained by solely containing Bi and In, respectively, Mg 2 Sn, Mg 9 Sn 5 , Mg 3 Bi 2 , Mg 3 an In like. Sn, Bi, the inclusion of more than 0.10% an In, the formation of these intermetallic phases is observed. Of these intermetallic phases, there are flat portion corrosion resistance and sacrificial corrosion resistance, and take into account that a soft easily encapsulated in Zn phase rich in plastic deformability to the extent that can be processed, Mg 2 Sn is most excellent . Mg 3 Bi 2 and Mg 3 an In is, Mg 2 somewhat flat portion corrosion resistance than Sn, poor performance balance such as sacrificial corrosion resistance and workability. [0062] 　Thus, at least, Mg as a fine MCSB phase 2 for producing a Sn, Sn is an essential element, the lower limit of the Sn concentration of 0.1% or more (preferably 3.0 or higher) to. [0063] 　However, although Bi and In are optional elements, Bi and In, the inclusion at the same time as Sn, Mg 2 replaces a portion of Sn Sn. That is, substitution of Mg least one Bi and In in a part of the Sn has substituted 2 to form Sn phase (fine MCSB phase). The substituted Mg 2 by the formation of Sn phase, it is possible to adjust the optimum Mg elution amount to impart planar portion corrosion resistance and sacrificial corrosion resistance. The substitution Mg 2 to generate an Sn phase, Sn, Bi and In, under the condition satisfying the Bi + In Ca , Y, La, and Ce is, Mg 2 replaces a part of Mg Sn. That, Ca in a part of Mg, Y, La, and at least one is substituted substituted Mg of Ce 2 to form Sn phase (fine MCSB phase). The substitution Mg 2 by generation of Sn phase, it is possible to adjust the optimum Mg elution amount to impart planar portion corrosion resistance and sacrificial corrosion resistance. 　Then, the substitution Mg 2 to generate an Sn phase, the lower limit of the Ca concentration is less than 0.05%, the lower limit of the Y concentration was 0.1% or more, the lower limit of the La and Ce each 0.1% more than is good. [0068] 　Meanwhile, Ca up to less 3.00%, Y until less 0.5%, La and Ce until each less than 0.5% (preferably Ca up less 1.00%, Y below 0.3% until, La and Ce each up to 0.3% or less) can contain. Ca, Y, La, and each concentration of Ce, Exceeding these ranges, Ca, Y, La, and Ce tends to intermetallic phases of the respective elements principal forms, corrosion resistance and workability Getting worse. Further, from the relationship between the substitution position of the fine MCSB phase, it is necessary to satisfy the Y + La + Ce ≦ Ca. Outside this condition, Y, La and Ce are made an intermetallic compound phase of each element mainly extremely flat portion corrosion resistance is deteriorated. [0069] 　In effect by substitution, Mg 2 Sn is as long sacrificial anti-corrosion is excellent caused structural changes. Substituted Mg 2 Sn phase (Bi, In, Ca, Y , substitution Mg according to at least one of La and Ce 2 clear distinction between Sn phase) is difficult but, Mg 2 Sn phase, by the substitution of any of the elements it is believed that the dissolution rate of the Mg can be appropriately controlled. Further, Mg 2 Sn phase, by the substitution of any of the elements, which will be described later Mg 9 Sn 5 is considered a change to the structure is produced. Bi, an In, Ca, Y, containing La and Ce (especially containing Ca) is simply replaced Mg 2 not only to form the Sn phase, Mg 2 cause changes in the crystalline form of Sn phase, Mg 9 Sn 5 phase is likely to be formed. This formation effect will be described later. 　Thus, for a long time, so as to exhibit high sacrificial corrosion resistance, when designing the plating layer, these elements containing is preferred. [0070] Si is smaller element of atomic size, to interstitial solid solution fine MCSB phase if small amounts. Therefore, Si is, Ca, Y, La, Ce, Bi, because it is smaller element than the atoms of In and the like, not the substitutional element fine MCSB phase forms the interstitial solid solution, fine MCSB phase (e.g. Mg 2 Sn phase, MgCaSn phase, Mg 9 Sn 5 phase etc.) has led to a change in any crystal structure, its details have not been ascertained. XRD, the TEM or the like, but a slight change in captured in the crystal structure, if confirmed by EPMA, Si containing traces are often observed in the fine MCSB phase and same position. [0071] 　Incidentally, the effect of Si traces are generally known growth inhibiting effect of the Al-Fe alloy layer, the corrosion resistance improvement effect has also been confirmed. Also interstitial solid solution to Al-Fe alloy layer. Detailed description of the formation such as the Al-Fe-Si intermetallic compound phase in the Al-Fe alloy layer is as already described above. [0072] 　Si also interstitial solid solution in Ca-Zn-Al intermetallic compound phase, which will be described later. Si solid solution effect of the Ca-Zn-Al intermetallic phase is not confirmed. The content of Si, the amount of Ca-Zn-Al intermetallic phase of Zn-Al-Mg alloy layer tends to relatively decrease. To form the Zn-Al-Mg alloy layer that makes full use of the characteristics of Ca-Zn-Al intermetallic compound phase, Si concentration it is preferable to be reduced. [0073] 　On the other hand, excess Si is a solid solution structure of fine MCSB phase collapses, Mg in Zn-Al-Mg alloy layer 2 to form an intermetallic compound phase of Si equality. Further, Ca, Y, if at least one of La and Ce is contained, Ca 2 to form an intermetallic compound phase of Si equality. [0074] 　Moreover, Si forms an oxide film of strong Si contained in the Zn-Al-Mg alloy layer surface. The Si-containing oxide coating is sacrificial protection property becomes Zn-Al-Mg alloy layer is eluted structure hardly decreases. In particular, a large effect of sacrificial protection property is lowered before corrosion early oxide film of the barrier of the Si-containing collapses. 　Further, it is Si Cr , Ti, Ni, Co, V , Nb, Cu, and Mn if a small amount of content, Mg 2 replaces a portion of Sn Sn. That is, a part of Sn, Cr, Ti, Ni, Co, V, Nb, Cu, and at least one is substituted substituted Mg of Mn 2 forming Sn phase (fine MCSB phase). These elemental concentrations are both must be less than the Sn concentration. Ca, Y, La, Ce, substituted Mg for Bi or In is substituted 2 Sn phase distinct sacrificial of change as (fine MCSB phase) hard to confirm. However, Sn substituted, since it forms a fine MCSB phase further bound to another Mg, can increase the amount of fine MCSB phase. Because it can increase the Mg to consume for forming fine MCSB phase thereto, tends to corrosion potential slightly sacrificial protection effect is increased moves somewhat less noble. [0078] 　However, there is a limit to the amount that can substituted. Or the concentration of one element of 0.25% or more, or if the total does not satisfy the Cr + Ti + Ni + Co + V + Nb + Cu + Mn <0.25 , even finer MCSB phase, to form an intermetallic compound phase containing elements mainly It can not ensure sufficient fine MCSB phase. For example, MgCu 2 as a phase, will form an intermetallic compound phase containing only one of the Mg element, the sacrificial corrosion resistance is lowered. Also, the coupling reaction proceeds, the corrosion resistance becomes extremely poor. Workability also becomes inferior. [0079] 　Therefore, Cr, Ti, Ni, Co, V, Nb, Cu, and Mn concentrations, and less than 0.25%, to satisfy 0 ≦ Cr + Ti + Ni + Co + V + Nb + Cu + Mn <0.25. [0080] 　by hot dipping, the case of forming a plating layer, a certain Fe concentration in Zn-Al-Mg alloy layer and Al-Fe alloy layer contained. 　Until Fe content of 5.0%, it has been confirmed no adverse effect on the performance included in the plating layer (in particular Zn-Al-Mg alloy layer). Many Fe, since it is often included in Al-Fe alloy layer, typically Fe concentration the thickness of the layer is large, increases. [0081] 　Sr, Sb, Pb and B, the influence of the formation of intermetallic phases of the fine MCSB equality is unknown. If a small amount dissolved in the Zn phase of the Zn-Al-Mg alloy layer, further it may be detected in the fine MCSB phase. For this reason, in some cases, play a role as a replacement element. Change of performance of these elements can not be seen in particular, but can result in a change in the appearance of the plating layer, it is possible to form spangles pattern on the surface of the plating layer. 　When these elements concentration of each of 0.5% or more, does not give influence on the formation of fine MCSB phase but can not be dissolved in the Zn phase. Therefore, to form a variety of intermetallic phases, workability and corrosion resistance is deteriorated. [0082] 　Therefore, Sr, Sb, concentrations of Pb and B, respectively, and less than 0.5%. Then, hardly substituted into fine MCSB phase, as an index intermetallic phases are easily formed, it is necessary to satisfy even Sr + Sb + Pb + B <0.5. [0083] 　impurity components contained in the raw material, or a component mixed in the manufacturing process, refers to a do not have intentionally containing component. For example, the plating layer, by mutual atomic diffusion between the plating bath and the steel material (the base steel), as an impurity, components other than Fe may also be incorporated trace. [0084] 　Next, a description will be given phase constituting the Zn-Al-Mg alloy layer. [0085] 　Zn-Al-Mg alloy layer has a Zn phase. Then, Zn Aichu has a fine MCSB phase (Mg-Sn intermetallic compound phase). That is, the fine MCSB phase is contained (i.e. encapsulated) in Zn phase. 　Zn-Al-Mg alloy layer, MgZn 2 may have a phase and Al phase. Then, Zn-Al-Mg alloy layer, Zn-Al-MgZn 2 does not include the ternary eutectic structure, or comprise may be also very small. [0086] 　Specifically, Zn-Al-Mg alloy layer, MgZn 2 and phase, and Al phase, a Zn phase containing the fine MCSB phase may be a tissue with. The phase of each phase, an area ratio, MgZn 2 the total amount of phase and Al phase may be exceeds the Zn phase containing the fine MCSB phase. For example, MgZn 2 and a total area ratio of the phase and Al phase 40-85% (preferably 50 ~ 75%), Zn phase 3 to 35% containing the fine MCSB phase (preferably 10-30%) and good it is. 　Since it has high corrosion resistance either phase, an excellent tissue plane portion corrosion resistance. Zn phase containing therein fine MCSB phase also easily fine MCSB phase portion eluted, but due rust effect of corrosion products that form as a result the corrosion resistance is improved as the equal or greater corrosion resistance as compared to the Zn phase It has. [0087] 　In the case where Ca and Si are contained in the plating layer, the Zn-Al-Mg alloy layer, Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase may be present, respectively . However, these metal compound phases is finely dispersed in the plating layer, its amount also is small, similar to the fine MCSB phase, it does not constitute the main phase of the Zn-Al-Mg alloy layer. [0088] 　If, Zn-Al-Mg the Zn phase alloy layer is more than half of the phase amount (in particular, Al concentration is less than 20.0% Mg concentration is less than 5.0%, and the Sn concentration is 3.0 true if) to one of the conditions below%, etc., the Zn-Al-Mg alloy layer, a fine Zn-Al-MgZn 2 ternary eutectic structure is likely to form. The ternary eutectic structure, since the corrosion by the coupling reaction proceeds easily, there is a tendency that each faster corrosion progress than plating structure comprising a coarse structure. Further, workability of the poor MgZn 2 becomes ternary eutectic structure, if present scattered finely Zn-Al-Mg alloy layer tends to be a starting point of cracks. In particular, the processing unit or the like, white rust is likely to occur in the early stage the cracks reaching the base iron (steel) innumerable. Therefore, the ternary eutectic structure is preferably better not to minimize formation. [0089] 　Here, the ternary eutectic structure is almost the Zn-Al-Mg alloy layer in the existing Zn-Al-Mg plated steel material contains (Fig. 1). 　Meanwhile, 1) a predetermined range of chemical composition of the plating layer of the present disclosure (particularly, limits Zn, Al, each concentration range) of Mg, MgZn 2 to increase the Airyo of phase and Al phase, 2) a fine elements constituting the MCSB phase (Sn, and other elements) be contained, and 3) by suitably controlling the manufacturing conditions of the hot-dip plating method, it is easy to avoid the formation of a ternary eutectic structure. As a result, loss or reduce this ternary eutectic structure. [0090] 　2, a SEM reflection electron image of a typical example of the plating layer of the present disclosure shown in FIG. As shown in FIG. 2, the Zn-Al-Mg alloy layer, for example, Zn phase, Al phase, MgZn 2 phase is present. Then, by the inclusion of Sn or the like, are included fine MCSB phase Zn phase. As a result, Zn-Al-MgZn 2 formation of a ternary eutectic structure can be suppressed. 　This is because the chemical composition of the plating layer of the present disclosure, the final solidification reaction, Zn-Al-MgZn by ternary eutectic reaction 2 is believed to be due to changes in the formation of fine MCSB phase from the formation of phases. Then, naturally, MgZn by a large amount of Mg 2 phase is formed in a large amount Zn-Al-Mg alloy layer, even in a relatively rigid plated steel becomes difficult processing, by the disappearance or reduction of ternary eutectic structure, sufficient processability is imparted Do not. [0091] 　Will now be described in detail finely MCSB phase (Mg-Sn intermetallic compound phase). 　Fine MCSB phase is hard phase when compared to Zn phase (particles), MgZn 2 is soft phase when compared to phase. Usually, hard intermetallic phases is plastic deformability is poor, the deterioration of the plastic deformability by finely precipitated Zn phase is extremely small. Therefore, when the fine MCSB phase is contained in the Zn phase, but increases the hardness processability of Zn phase hardly deteriorated. 　On the other hand, the increase of the fine MCSB phase, very plastic deformability poor MgZn 2 phase amount of phase is slightly reduced. Therefore, the increase of the fine MCSB phase is expressed effect leading to improved workability. 　These phenomena, excellent wear resistance at high hardness, and further, the plating layer formability is compatible even at high hardness. 　Incidentally, like the fine MCSB phase, Ca-Al-Si intermetallic compound phase, and Mg-Al-Si intermetallic compound phase is also a hard material, MgZn 2 is soft phase when compared to phase. Therefore, workability by the inclusion of these intermetallic phases are hardly deteriorated. [0092] 　Here, the hardness of the plating layer may be at an average Vickers hardness is not less than 150 Hv. Plating layer is not less than 150Hv at an average Vickers hardness is typically harder than the existing Zn-Al-Mg plated layer, a plating layer is usually difficult machining. However, the organization control of the Zn-Al-Mg alloy layer in the present disclosure, certain V machining of the plating layer is achieved existing Zn-Al-Mg plated steel sheet such as bending equivalent processability in the range of R values the resulting. [0093] 　By including the fine MCSB phase in Zn phase, it is possible to control the proper dissolution rate of the plating layer. When Zn phase fine MCSB phase is not taken, the fine MCSB phase lose immediately the effect of eluted early fine MCSB phase by uneven distribution. Moreover, since the dissolution of Zn can not be obtained, the corrosion products which are suitable for corrosion protection is not formed. [0094] 　The formation of Zn phase containing fine MCSB phase, Zn-Al-MgZn 2 for ternary eutectic reaction phase disappears, Zn phase containing ternary eutectic structure and the fine MCSB phase is hard to coexist. In Zn-Al-Mg alloy layer section, Zn phase containing fine MCSB phase, the area fraction of 3% or more, if particularly present in Zn-Al-Mg alloy layer at least 5%, terpolymer crystal structure that has almost disappeared have been found experimentally. Further, since the three-way eutectic structure disappears, improvement is seen in workability and planar portion corrosion resistance. Further, even it turned into high-Mg higher than commercial Zn-Al-Mg plated, able to exert the planar portion corrosion resistance, commercial Zn-Al-Mg plated comparable workability can be ensured. 　However, in order to maintain the planar portion corrosion resistance, adhere to the chemical composition range of the plating layer defined in the present disclosure, the fine MCSB phase, Ca-Zn-Al intermetallic phase, Ca-Al-Si intermetallic compound phase , and Mg-Al-Si intermetallic shall inhibit the formation of intermetallic phases comprising a factor to extremely deteriorate the flat portion corrosion resistance than compound phase. When such intermetallic phase is formed, there is a case where the planar portion corrosion resistance even Zn phase is present is deteriorated containing fine MCSB phase. [0095] 　Zn-Al-MgZn due to the presence of Zn phase containing fine MCSB phase 2 confirm the disappearance of the ternary eutectic structure, when conforming to the chemical composition and plating method for manufacturing a plated layer in the present disclosure, the final solidification as described above reaction, Zn-Al-MgZn by ternary eutectic reaction 2 rather than coagulation phase, because due to the formation of fine MCSB phase. Checking for formation of a ternary eutectic structure of the plating layer, the tissue observation by SEM observation of any plating layer cross-sectional structure (e.g., an acceleration voltage 15kV or less, the magnification filament current 2 ~ 3A, in emission current 100 ~ 200 .mu.A , confirmation by about 1000-fold) is the most preferred [0096] 　Here, FIG. 3 shows an example of a fine MCSB phase contained in Zn phase. As shown in FIG. Fine MCSB phase, not to the most grain size 1μm in one phase itself very fine, innumerable present in Zn phase. This, in the course of solidification of the plating layer, Mg, Ca, Sn, expelling Bi or the like occurs from the reduction in solubility limit due to temperature drop of Zn phase, due to bound Thus formed of these elements. Fine MCSB phase precipitated through this process is contained always Zn phase, empirically in melt plating method, often become crystal grain size less than 1μm fine MCSB phase, it is precipitated in patchy . 　Therefore, fine MCSB phase contained in Zn phase is less than the average grain size 1μm are preferred. The lower limit of the average crystal grain size of the fine MCSB phase is not particularly limited, for example, is 0.05μm or more. 　However, the fine MCSB phase is mainly formed, if a long time held in the atomic diffusion can temperature range (0.99 ~ 350 ° C. vicinity) is also observed grain size 1μm or more MCSB phase. However, the presence position is mainly that there is no change in a Zn phase, the initial state, and grow and aggregate finely dispersed have fine MCSB phase with each other, only the particle size is large . For this reason, the impact of the flat portion corrosion resistance, etc., little. 　Here, the planar portion corrosion resistance and sacrificial corrosion resistance are contradictory performance, when importance is attached to both performance, it is preferable to the presence of fine MCSB phase. On the other hand, when designing the plating layer sacrificial protection property is important, in a portion of the MCSB phase above grain size 1 [mu] m, it is preferable to greatly grown Zn-Al-Mg layer. 　Incidentally, the crystal grain size 1μm or more MCSB phase corresponds to bulk MCSB phase to be described later. [0097] 　When Zn phase fine MCSB phase is contained it is present, the corrosion potential of the plating layer decreases dramatically. Specifically, for example, the corrosion potential of the plating layer, the corrosion potential indicated by the ordinary Zn-Al-Mg-based hot dip plated layer [-1.0 ~ -1.1V (vs.Ag/AgCl reference electrode 5% NaCl from an aqueous solution)], the content of fine MCSB phase drops to near minimum -1.5V. To confirm the very early corrosion behavior, electrochemical measurement is an effective means. Becomes lower corrosion potential of the plating layer due to the presence of fine MCSB phase, than ordinary Zn-Al-Mg-based molten plating layer, earlier a protection effect on elemental (Mg, Ca, etc.) is dissolves, in particular base steel ( inhibit red rust of base iron (steel) cover the steel material). The reduction in the potential, the element with corrosion protection (Mg, Ca, etc.) from the location, since it becomes possible to move far not been possible in conventional Zn-Al-Mg-based molten plating layer, cut edge corrosion-resistant effect of the parts can be expected. [0098] 　Containing Zn phase of the fine MCSB phase can be confirmed by X-ray diffraction using Cu-K [alpha line (XRD). Usually, in XRD Mg 2 if the diffraction peak of Sn, for example, JCPDS card: PDF # 00-007-0274, # 00-006-0190, typified by # 00-002-1087. However, the Zn-Al-Mg plated layer, the optimum diffraction peaks to identify fine MCSB phase, Zn phase, MgZn 2 phase is a 22.8 ° to Al phase and a diffraction peak does not overlap. Diffraction peaks used to identify the fine MCSB phase, other 22.8 °, 23.3 °, and 24.2 ° are not-overlapping and configuration phases of the other plating layers, to identify a fine MCSB phase it is a good diffraction peak convenient to. 　In addition to the sn, Bi, an In, a containing Ca or the like, in conventional Zn-Al-Mg plated layer, originally, bulk MgZn 2 present as phase or Zn-Al-MgZn 2 present as ternary eutectic structure it was MgZn 2 phase (or Mg phase) decreases, changes to fine MCSB phase. MgZn 2 identification of phases, for example, PDF # 00-034-0457 is but typical, the strongest line 41.3 ° is a measure of abundance. Normally, the presence of fine MCSB phase became more crowded, the peak intensity decreases. [0099] 　Specifically, using a Cu-K [alpha rays, X-ray output was measured under the conditions a 40kV and 150 mA, the X-ray diffraction pattern of the plating layer surface, specific strength I (fine MCSB phase) = {I ( 22.8 ° strength (cps)) + I (23.3 ° intensity (cps)) + I (24.2 ° intensity (cps))} / 3 × I (background intensity at 20 ° (cps)) is 1. When 5 or more (more preferably 3.0 exceeded) is, as an index that Mg is present sufficiently as a fine MCSB phase. Then, so lower corrosion potential than the corrosion potential (-1.0 ~ -1.1 V) indicated by the existing Zn-Al-Mg plated layer is clearly observed. In other words, indicates to the background, the diffraction peaks of the fine MCSB phase distinguishable exist. The presence of fine MCSB phase, improving sacrificial corrosion resistance (particularly, improvement in the cutting end face corrosion resistance) is able to see clearly. [0100] 　As a method of calculating the intensity of the background, but in recent years there is a software that can perform background subtraction or the like, from the data of the diffraction peak intensities obtained by creating a 2θ and intensity (cps) graph, 15 ° to create an approximate line of the flat portion is confirmed in ~ 25 ° (the straight line). From the plating layer surface of the present disclosure, for 15 °, it does not appear in a diffraction peak at 25 °, simply, 15 °, Taking the average value of the intensity of cps 25 °, the background intensity at 20 ° is found. Should, 15 °, 25 if ° is possible that a diffraction peak overlap employs a mean value of 15 ° (± 1 °) and 25 °, or 15 ° and 25 (± 1 °). [0101] 　When fine MCSB phase is present in the Zn phase, along with the preceding corrosion of the fine MCSB phase, Cl - , OH - attract ions such as, corroding surroundings. Therefore, originally, also poorly soluble Zn phase itself as compared with Mg and Ca dissolved a certain amount, other Mg and Ca, Zn also eluted, Zn anticorrosive effect is also added. Further, the Zn-Al-Mg alloy layer, since the Sn that disconnecting Mg and Ca, Bi or the like are left without moving as a single metal, partly can electrochemically noble part Zn phase , further Zn of its surroundings become a corrosive environment. Originally, Mg and Ca, Mg (OH) on base iron (steel) 2 and Ca (OH) 2 present as a high solubility and hence water, stably be held on the plated surface and the steel matrix it is difficult. 　However, by Zn ions are eluted simultaneously, Mg (OH) 2 and Ca (OH) 2 Zn-based corrosion products in the presence of an alkali environment is formed. In that Zn-based corrosion products, it is captured Mg and Ca elements, it is possible to form a coating of Zn-Mg-Ca intermetallic phase to protect the base steel in a short period of time. 　Therefore, including tissue fine MCSB phase Zn phase, compared with mere fine MCSB phase was containing tissue (i.e. fine MCSB phase was formed in the Zn Aisoto tissue), the amount of corrosion sacrificial protection property becomes higher but increases immediately for high anticorrosion effect film is formed, the corrosion resistance is often improved rather. By controlling the phase of fine MCSB phase and Zn phase, its effect (elution range, anti-corrosion period) can be controlled. [0102] 　In particular, Zn phase containing fine MCSB phase, 3% or more (preferably 10% or more) in an area fraction (for the cross section of the Zn-Al-Mg alloy layer) The presence, elements eluted early in the plating layer increases the tendency to immediately form an anti-corrosive coating. Therefore, further sacrificial corrosion resistance (especially cut end face corrosion resistance) is improved. [0103] 　On the other hand, in Zn phase containing fine MCSB phase, fine MCSB phase (i.e., grain size Mg-Sn intermetallic compound phase of less than 1 [mu] m) is the area fraction (area fraction for Zn phase containing the fine MCSB phase) When in 10-50% (preferably 15-35%) is present, early eluted elements from the plating layer is increased tendency to immediately form a rust preventing film. Thereby further sacrificial protection property (especially cut end face corrosion resistance) is improved. 　Thus, in the cross section of the Zn-Al-Mg alloy layer, the area fraction of minute MCSB phase to Zn phase containing fine MCSB phase (i.e., Mg-Sn intermetallic compound phase of less than the crystal grain size 1 [mu] m) is 10 ~ preferably 50%. [0104] 　Then, for effectively improving the sacrificial corrosion protection for the "Ca-containing effect" it will be described. 　When Zn-Al-Mg alloy layer of Ca is contained, Mg 2 replaces a part of Mg Sn. For example, the substitution of Mg Ca concentration and 0.05 ~ 3.00% 2 Sn phase formation, such as "MgCaSn phase" is (fine MCSB phase) is observed. Mg 2 as Sn Airyo often, increasing the amount which can be varied to MgCaSn phase. Moreover, Mg is not replaced 2 Sn, the crystal structure changes, Mg 9 Sn 5 transforms into. Mg 2 as the Sn amount is large, Mg 9 Sn 5 also increases. 　That is, when the Ca concentration and 0.05 to 3.00 percent, as a fine MCSB phase, MgCaSn phase and Mg in Zn phase 9 Sn 5 containing phase. [0105] 　Generation of MgCaSn phase and Mg 9 Sn 5 the transformation to phase progresses, improved sacrificial protection of the plating layer, long sacrificial protection is enhanced. Ca which contains all Mg 2 indicators and Mg incorporated into the Sn 9 Sn 5 is an indicator of transformation to phase required. Detection of this Ca is captured fine MCSB phase originally, it is preferable to confirm that Ca is detected at the same position as the Mg position TEM or EPMA. However, it is possible to use the Cu-K [alpha rays, X-ray output was measured under the conditions a 40kV and 150 mA, confirmed by X-ray diffraction pattern of the plating layer surface. [0106] 　Normally, Mg in XRD 2 diffraction peaks of Sn is also applicable in Zn-Al-Mg plated layer, 22.8 °, 26.3 °, 37.6 ° is Mg 2 used in the detection of Sn unique diffraction peaks is a typical diffraction peaks. Meanwhile, MgCaSn, for example, JCPDS card: # 01-072-5710, Mg 9 Sn 5 but is represented by # 01-073-8010, for example, the diffraction peak of 23.3 ° is whether or Ca not, Mg 2 even Sn, MgCaSn, Mg 9 Sn 5 is a diffraction peak detected even. [0107] 　Here, 22.8 °, a diffraction peak of 26.3 ° is smaller when Ca concentration is high, is hardly detected by the Ca substitution. Even 37.6 ° exhibit the same tendency, there is a large diffraction peak around, not suitable for identification. [0108] 　The degree of Ca substitution intensity of these angles as an index, i.e. MgCaSn phase and Mg 9 Sn 5 can measure the formation of the phase. Specifically, the following formula: specific strength I (MgCaSn + Mg 9 Sn 5 ) = {I (22.8 ° intensity (cps)) + I (26.3 ° intensity (cps))} / I ( 23.3 ° strength (cps)) is less than 0.3 (preferably less than 0.1), and I (23.3 ° intensity (cps) if a) at least 500 cps, Mg 2 Sn phase (fine MCSB phase) Zn present in -al-Mg alloy layer, there is Mg 2 Mg position of Sn is nearly all Ca substitution, MgCaSn phase and Mg 9 Sn 5 phase is mainly. 　Incidentally, I (23.3 ° intensity (cps)) is of less than 500 cps, the first place sufficient, Mg 2 for Sn phase (fine MCSB phase) is not present in the Zn-Al-Mg alloy layer, specific strength I (MgCaSn + Mg 9 Sn 5 ) good be 0.3 or more. [0109] Mg 　by Ca substituted 2 performance change of Sn phase (fine MCSB phase) is as follows. Ca is Mg 2 when the captured MgCaSn phase in Sn phase, Mg 2 without changing sacrificial of Sn phase (corrosion potential), can be suppressed moderately Mg elution volume. As a result, so high sacrificial protection effect over a longer obtained. Mg 9 Sn 5 phase is also the same effect. These effects, other electrochemical measurements can see the effect in various corrosion tests, and the like. 　Incidentally, it is possible to ascertain other than Ca Y, Ce, La, In-containing effect similar fashion Bi and In. Further, MgCaSn phase and Mg by a change in the crystal structure 9 Sn 5 there is a case where phase trace metals Sn phase around is detected, because it is a small amount, a large change in performance is not negligible. [0110] 　It will now be described Si-containing effect. 　As Si is when contained indicated above, Si is interstitial solid solution fine MCSB phase, crystal structure becomes more complicated. In this case, it tends to change the preferred crystal orientation of the fine MCSB phase. Therefore, for example, "MgCaSn phase and Mg corresponding to fine MCSB phase 9 Sn 5 when there is a phase", even not satisfy the evaluation index, there are exceptional plating layer sacrificial protection effect can be obtained. 　For example, Ca, if Si and high concentration of Mg is contained (specifically, Mg concentration is 4.0% ultra-than 12.5%, a Ca concentration of 0.05 to 3.00%, Si when the concentration satisfies 0.01 to 2.5%), a portion, exceptional plating layer which is not included in the index appears. In such a plating layer, Ca, if Si and Mg satisfy the above chemical composition, by setting a new indicator in the strength of the resulting XRD, to define effects containing Si in fine MCSB phase it can. [0111] 　First, as a precondition, the ratio intensity I (fine MCSB phase) = {I (22.8 ° intensity (cps)) + I (23.3 ° intensity (cps)) + I (24.2 ° intensity (cps)) } / 3 × I met (background intensity (cps) at 20 °) is 1.5 or more, and, among the diffraction peaks appearing at 23.0 ~ 23.46 °, a diffraction peak of the strongest intensity 23.36 When appearing between ~ 23.46 °, the ratio intensity I (MgCaSn + Mg 9 Sn 5 be not satisfied), high sacrificial corrosion prevention effect can be confirmed. In other words, highest intensity angle of the diffraction peaks due to Si-containing fine MCSB phase (diffraction peak with 23.3 ° reference) (2 [Theta]) is, if appearing at 23.36 ~ 23.46 °, high sacrificial protection effect effect can be confirmed. [0112] 　For example, normally, when it corresponds to a fine MCSB phase MgCaSn phase and MgCaSn phase does not contain Si, diffraction peaks relative to the 23.3 °, the strongest strength between 23.25 ° ~ 23.35 ° appears, but when MgCaSn phase and MgCaSn phase contains Si, that the crystal lattice of MgCaSn phase and MgCaSn phase is distorted, the strongest intensity appears between 23.36 ~ 23.46 °. The Si-containing fine MCSB phase (Si-containing MgCaSn phase and Si-containing MgCaSn phase), MgCaSn phase and Mg containing no Si 9 Sn 5 shows the same effect as phase. That is, in terms of long-term sacrificial corrosion protection, corrosion rate of the fine MCSB phase is optimized. [0113] 　Si is likely to bind to the Ca-Al intermetallic phase and Mg-Al intermetallic phase. The content of the intermetallic compound phase in which these Si are bonded, can impart special properties. 　Specifically, Ca concentration from 0.05 to 3.00 percent, at a Si concentration of 0.01 to 2.5% when Ca and Sn are contained respectively, Ca-Al-Si intermetallic compound phase, and forming at least one of the phases is the Zn-Al-Mg alloy layer is selected from the group consisting of Mg-Al-Si intermetallic compound phase can be confirmed by SEM or the like. 　The average crystal grain size of the Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase is 1μm or more. If the average crystal grain size is 1μm or more, Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase is a particle size sufficient size to be identified by TEM. Therefore, Ca-Al-Si intermetallic not have a threshold of special performance to the average lower limit of the crystal grain size of the compound phase and Mg-Al-Si intermetallic compound phase. On the other hand, the upper limit of the average crystal grain size of the Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase is not particularly limited, for example, to 30μm or less. [0114] 　Process for producing a plated layer, or from chemical composition, growth behavior or location of Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase is changed. When using quenching during solidification of the plating layer, small particle size, fine Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase to form a large number. On the other hand, when using mildly, large particle size, the number is also reduced. [0115] 　Incidentally, Ca-Al-Si intermetallic compound phase, usually, often exhibit the form of a needle or bar shape. Mg-Al-Si intermetallic compound phase often exhibits a form of irregular or spherical. However, there are some exceptions, in some cases also becomes irregular in Ca-Al-Si intermetallic compound phase. On the other hand, it may be a rod-like or needle-like in Mg-Al-Si intermetallic compound phase. [0116] 　When formation of the Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase is "needle or bar", the length of the longest line (diagonal line, etc.), Ca-Al-Si intermetallic compound the crystal grain size of the phases and Mg-Al-Si intermetallic compound phase. When formation of the Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase is "irregular or spherical than the needle or bar", the equivalent circle diameter of the area, Ca-Al-Si intermetallic crystal grain size of the compound phase and Mg-Al-Si intermetallic compound phase to. [0117] 　Here, in FIG. 8, an example of the plating layer of the present disclosure, a cross-sectional showing a, Ca concentration from 0.05 to 3.00 percent, at a Si concentration of 0.01 to 2.5% SEM reflection electron image of a cross section of the plating layer Ca and Sn, each containing (SEM reflection electron image of the plating layer 10 ° oblique section) showing. 　10, in FIG. 8 shows an enlarged image of the tissue of the plating layer in the white frame to (SEM reflection electron image). [0118] 　As shown in FIGS. 8 and 9, Ca concentration from 0.05 to 3.00 percent, at a Si concentration of 0.01 to 2.5% when Ca and Sn, each containing, for example, grains in the plating layer or the amorphous Mg-Al-Si intermetallic compound phase, the acicular Ca-Al-Si intermetallic compound phase exists. [0119] 　Further, in FIG. 10, in FIG. 8 shows an enlarged image of the vicinity of the interface between the base steel plating layer (steel) to (TEM images). 　In FIG. 11A, in FIG. 10, showing an electron beam diffraction image of the irregular intermetallic phase (13), in FIG. 11B, the EDS spectra in Figure 10 irregular intermetallic phase (13). 　Figure 12A, in Figure 10, shows an electron beam diffraction image of the needle-like intermetallic compound phase (14), the EDS spectra of Figure 10 in acicular intermetallic phase (14) in FIG. 11B. [0120] 　In Figure 10, the amorphous intermetallic compound phase (13), the electron beam diffraction image, as shown in (FIG. 11A) and EDS analysis spectrum (FIG. 11B), Mg, Al and Si are detected (Zn back ground, Cu analysis method due). Therefore, amorphous intermetallic phase (13), Mg-Al-Si compound phase (MgAlSi phase as an example) to be identified. 　In Figure 10, the needle-like intermetallic compound phase (14), as shown the electron beam diffraction image (14A) and EDS analysis spectrum (FIG. 12B), a needle-like intermetallic phase, Ca, is Al and Si is detected (Zn background, Cu analysis method due). Therefore, acicular intermetallic phase (14) is identified as Ca-Al-Si compound phase. [0121] 　Thus, Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase, as shown in FIGS. 11A and 12A, even when analyzed by electron diffraction image of the TEM or the like, past, If you can not match the discovered intermetallic phase is large. On the other hand, the EDS analysis, as shown in FIGS. 11B and 12B, Ca, Al and Si, or Mg, since the Al and Si are simultaneously detected, if it is an intermetallic compound phase containing these elements it is possible to identify. 　That, Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase can be identified by electron beam diffraction image and EDS analysis of the TEM or the like. In addition to Zn, if Ni is contained in the plating layer may Zn, elements such as Ni are also detected at the same time. [0122] 　Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase, will form in preference to the fine MCSB phase, in addition to reducing the fine MCSB phase, de-Ca from fine MCSB phase, de Y, which may cause de-La, or de-Ce. However, the amount Ca concentration is sufficient, for example, if it is contained more than 0.05%, no particular need to worry. [0123] 　Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase, ductility poor relatively hard. These average crystal grain size 1μm or more intermetallic phase, in a large amount present in the Zn-Al-Mg alloy layer, the plating layer becomes so divided minutely during processing. For example, when carrying out the T bend test or the like, bent outward (tensile side) the top of the processing unit, if these intermetallic phases are not present (e.g., if the Ca and Si is not contained) in comparison with the plating layer It is destroyed finely. Usually, the plating layer of the alloy system, since poor ductility when compared with the base steel (steel), a number of base steel (steel) in the crack under the plating layer exposed portion appears. 　When one crack width is large, the plating layer is excessively and sacrificial protection, to the base steel bare portion at the crack is covered with rust, fallen sacrificial protection ability in the processing unit, the processing unit corrosion resistance is degraded. 　Meanwhile, one crack width and is small (i.e., when the plating layer is cracked finely), because the sacrificial protection is appropriate, sacrificial protection ability in the processing unit also becomes appropriate, small degradation of the processed portion corrosion resistance . 　That is, the corrosion resistance improving effect during machining and the average crystal grain size 1 [mu] m or more Ca-Al-Si intermetallic compound phase and an average of more than grain size 1μm Mg-Al-Si intermetallic compound phase exists is obtained. [0124] 　Thus, in view of the processing unit improving corrosion resistance, Zn-Al-Mg alloy layer, the above average crystal grain size 1μm Ca-Al-Si intermetallic compound phase and an average grain size 1 [mu] m or more Mg-Al it is that at least one is present selected from the group consisting of -Si intermetallic phase. [0125] 　Further, from the viewpoint of improving the effective processing portion corrosion resistance, surface integral of each crystal grain size 1μm or more Ca-Al-Si intermetallic compound phase and grain size 1μm or more Mg-Al-Si intermetallic compound phase (area fraction for the cross section of the Zn-Al-Mg alloy layer) ratio is preferably less than 0 than to 1%. Incidentally, the chemical composition of the plating layer of the present disclosure, Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase, respectively, that alone occupy a large area ratio fraction (1% or more) no. [0126] 　Incidentally, T songs test, usually, 0T bend (completely crushed, bent 180 degrees) found the following, 4T bending etc. than (bending leaves a space thickness 4 sheets inside), the processing is severely processed by cracking unit easy corrosion resistance of the deterioration has been confirmed. The Zn-Al-Mg alloy layer, the at least one of Ca-Al-Si intermetallic phase and Mg-Al-Si intermetallic compound phase finely dispersed, in any such processing conditions, the plating layer is cracked finely Therefore, hardly affected by the strength of the processing site. [0127] 　It will now be described Ca-Zn-Al intermetallic phase. 　If the Ca concentration of 0.05 to 3.00% (preferably 0.10 to 1.00%), there are sufficient Ca respect Sn, the position that can be substituted for Mg fine MCSB phase Whilst it may be combined with Zn and Al in Zn-Al-Mg alloy layer. This Ca originally, combined with Zn, CaZn intermetallic phase (CaZn 2 phase, CaZn 5 phase, CaZn 11 equality) is for easily formed. If Ca concentration is high, because very easily segregated, intermetallic phase binding is not fixed to one of the. The chemical composition of the present disclosure, Ca-Zn metallic compound phase portion is replaced by Al with Ca-Zn-Al intermetallic compound phase of Zn (hereinafter also referred to as "CZA phase") is formed. [0128] 　CZA phase is little effect on the grant of the sacrificial corrosion protection, when contained in the Zn-Al-Mg alloy layer is planar portion corrosion resistance is improved. Further, the CZA phase is precipitated, for the hardness of the plating layer, since in the direction in which the Al phase of the soft decreases slightly increased, the wear resistance is improved. Usually, the improved planar portion corrosion resistance, because the elution of the constituent elements of the plating layer anticorrosive effect is reduced, the sacrificial protection effect decreases. However, since the CZA phase has no effect on the dissolution of the fine MCSB phase, reduction of the sacrificial corrosion protection is not triggered. [0129] 　In particular, in the cross section of the Zn-Al-Mg alloy layer, the crystal grain size 1μm or more CZA phase is 5% or more (preferably 10% or more) in an area fraction for the cross section of the Zn-Al-Mg alloy layer when present, flat portion corrosion resistance is improved. For example, white rust generation amount of the salt spray test (SST) is accelerated corrosion test is reduced. 　On the other hand, when the area fraction of crystal grain diameter 1μm or more CZA phase exceeds 5.0%, corrosion resistance conversely tends to decrease. Further, originally, since CZA phase is very hard phases, the Vickers hardness of the plating layer is rapidly increased, processability tends to decrease. Therefore, the lower limit of the area ratio of crystal grain diameter 1μm or more CZA phase is preferably 5.0% or less, more preferably 2.0%. 　Note that the upper limit of the crystal grain size of CZA phase, without limitation, for example, is 10μm or less. [0130] 　CZA phase, a Zn-Al-Mg alloy layer may typically have a variety of shapes (cubic, needle-like, rod-like, amorphous, etc.). When formation of CZA phase is "square, needle, bar", the length of the longest line (diagonal line, etc.), and crystal grain size of the Ca-Zn-Al intermetallic phase. When formation of CZA phase is "square, needle, amorphous non-stick", the equivalent circle diameter of the area, and the crystal grain size of the CZA phase. [0131] 　The presence of CZA phase, it is preferable to confirm by TEM. Further, in EPMA, also by checking the Al that is not detected at the same position as the Zn position of Ca-Zn intermetallic compound phase, it is possible to confirm the presence of CZA phase. Further, by X-ray diffraction using Cu-K [alpha line (XRD), it is possible to confirm the presence of CZA phase. 　Usually, the diffraction peaks of CZA in the XRD, CaZn 2 JCPDS card: PDF # 00-028-0257, CaZn 5 : there is a PDF # 00-010-0239 like. However, the diffraction peak caused by CZA is, 33.3 °, also appears to 35.0 °. 　In the case where sufficient Ca is present with respect to Sn, as described above, Mg 2 Sn is approximately Mg 9 Sn 5 is changed to the crystal structure of the. Therefore, Mg 9 Sn 5 that the diffraction peak attributable to 10.4 ° being confirmed only in the presence is detected, can be employed as the presence indicator of CZA phase. [0132] 　As an indicator of the strength of these angles, it is possible to measure the degree of formation amount for CZA phase of fine MCSB phase, using a Cu-K [alpha rays, X-ray output was measured under the conditions a 40kV and 150 mA, the in X-ray diffraction pattern of the plating layer surface, the following equation: specific strength I (CaZnAl) = {I (10.4 ° intensity (cps)) + I (33.3 ° intensity (cps) + I (35.0 ° intensity ( if cps))} / I (23.3 ° intensity (cps)) is 0.5 or more, it has been found to be 5% or more in area fraction of CZA phase. [0133] 　Next, a description will be given grain size 1μm or more MCSB phase (bulk MCSB phase). 　The Zn-Al-Mg alloy layer may the grain size 1μm or more MCSB phase is present. For example, the base steel exposed portion is large steel material, than to improve the flat portion corrosion resistance, better to increase the sacrificial corrosion protection is, since it is possible to suppress instantaneous corrosion from base iron (steel) bare portion, MCSB phase than having all finely deposition, it is preferable that the large massive part of the MCSB phase. 　When bulk MCSB phase is present, it can be secured even better sacrificial protection property. The upper limit of the grain size of the bulk MCSB phase is not particularly limited, for example, to 20μm or less. 　Strictly managing Sn concentration (specifically, 3.00 to 20.00% the Sn content in mass%, and, when the contents of the elements of each of Sn and Zn, wherein: 0. 05