DESCRIPTION TITLE OF THE INVENTION Alloyed Hot-Dip Galvanized Steel Sheet 5 TECHNICAL FIELD [ OOOl] The present invention relates to an alloyed hot-dip galvanized steel sheet. More specifically, the present 10 invention relates to a high-strength alloyed hot-dip galvanized steel sheet, which is capable of easily realizing a high strength (for example, a tensile strength of 980 MPa or more), is excellent in the coating adhesion, and is suitable as a member in automotive 15 field, home appliance field, building material field, and the like. BACKGROUND ART [0002] 2 0 Heretofore, alloyed hot-dip galvanized steel sheets have been used mainly in the automotive field. However, in the plating layer of the alloyed hot-dip galvanized steel sheet, a Zn-Fe alloy layer, which is inferior in the ductility to the underlying steel sheet, is present. 25 In a case where a tensile strength of 980 MPa or more is required, this layer has been considered to be a problem, because the plating (or coating) adhesion thereof is poor and the plating is liable to be separated from the interface between the plating and the underlying steel 30 sheet, at the time of working such as press molding, to thereby readily cause an appearance failure such as indentation mark. Therefore, Patent Document 1 describes, as a measure for improving the plating adhesion, a method of enhancing 3 5 the plating adhesion by a so-called anchor effect, that is, by increasing the unevenness at the interface between the coating and the underlying steel sheet. Also, Patent Document 2 discloses that when a steel sheet is heated, and then is pickled, and after the removal of the oxide layer on the surface, is subjected to plating, to thereby improve the adhesion. 5 Also, Patent Document 3 discloses a high-strength high-ductility hot-dip galvanized steel sheet containing, in terms of volume fraction, from 30 to 90% of a ferrite phase, 5% or more of bainite, 10% or less of martensite, and from 5 to 30% of a retained austenite phase. Patent 10 Document 4 discloses a high-strength cold-rolled steel sheet, where the density of dislocations contained in the steel sheet is 8x10'' (dislocations/rnrn2) or less, and the static/dynamic ratio (=FS2/FS1) as a ratio between a quasi-static strength (FS1) at a strain rate of 0.0067 ( s - 15 I), and a dynamic strength (FS2) at a strain rate of 1,000 (s-l) is 1.05 or more. Patent Document 5 discloses an alloyed hot-dip steel sheet comprising a base iron, and a specific plating layer disposed at least on one surface thereof, wherein plating layer does not have an q phase 20 or < phase in the plating layer surface, the plating layer has a composition of Fe: from 8 to 12% and Al: from 0.05 to 0.25%, with the balance being Zn, and the r phase at the interface with the base iron is l.O/pm or less. However, in the prior art, the difference in 25 ductility between the plating layer and the underlying steel sheet, which may be fundamentally a main factor contributing to the plating adhesion, has not been solved, and therefore, the plating (or coating) separation cannot be prevented from occurring during 3 0 severe working. RELATED ART PATENT DOCUMENT [0003] 3 5 [Patent Document 11 JP-A (Japanese Unexamined Patent Publication; KOKAI) No. 2011-94215 [Patent Document 21 JP-A No. 2002-173756 [Patent Document 31 JP-A No. 2005-133201 [Patent Document 41 JP-A No. 2002-30403 [Patent Document 51 JP-A No. 64-68456 5 SUMMARY OF THE INVENTION PROBLEM TO BE SOLVED BY THE INVENTION [0004] An object of the present invention is to provide an 10 alloyed hot-dip galvanized steel sheet with a high strength (for example, a tensile strength of 980 MPa or more), which can be prevented from plating separation during working. Another object of the present invention is to 15 provide a high-strength alloyed hot-dip galvanized steel sheet, which is excellent in the plating adhesion. MEANS FOR SOLVING THE PROBLEM [0005] 20 As a result of earnest study, the present inventors have found that when the ductility of a steel sheet itself can be reduced by the structure control of the steel sheet and further, the ductility of the plating itself is increased by controlling the amounts of T1 25 phase and r phase in the plating phase, the plating separation can be suppressed. [0006] As a result of further study based on the above discovery, the present inventors have also found that 3 0 when the total thickness of T1 phase and r phase present in the alloyed hot-dip galvanized layer is set to 2 pm or less, and the thickness of I-1 phase having the lowest ductility among Zn-Fe alloy phases is set to be smaller than that of the I- phase, the plating adhesion can be 35 further enhanced. [00071 According to the knowledge and investigations of the present inventors, the mechanism for providing the abovedescribed effect in the present invention may be presumed as follows. 5 That is, the present inventors have found that fundamentally, even when the ductility of plating layer is increased, the rl phase (Fe5Zn2l, Fe content: 18% or more and less than 24%) and the r phase (Fe3Znlo, Fe: 24% or more and 32%nor less), which may be inevitably 10 produced at the interface between the plating layer and the underlying steel sheet in an alloyed hot-dip galvanized layer, can hardly have a higher ductility than the ductility of the underlying steel sheet, and the plating cannot follow the deformation of the underlying 15 steel sheet during working, to thereby cause plating separation. On the other hand, the present inventors have also found that when the ductility of a steel sheet itself is reduced by the structure control of the steel sheet, and 2 0 the ductility of the plating itself is increased by controlling the amounts of T1 phase and r phase in the plating phase, the plating separation can be suppressed. In a case where the ductility of a steel sheet itself is reduced, it can be assumed that the workability of the 25 steel sheet may be lowered as compared to that of a conventional steel sheet, and a crack may be early generated in the underlying steel sheet, to thereby cause fracture. However, in the present invention, plating is applied to a steel sheet while controlling the amounts of 3 0 rl phase and r phase therein, so that fracture of the steel sheet can be prevented at the same level as, or to a higher level than that of the conventional steel sheet. The reason why such a phenomenon occurs may not be necessarily clear, but the present inventors may presume 3 5 that although a crack may be early generated in the underlying steel sheet, because plating with excellent ductility is present on the steel sheet in the present invention, the stress concentration on the cracking part may be relieved. [OOOS] 5 That is, the present invention relates to a highstrength alloyed hot-dip galvanized steel sheet excellent in elongation and plating adhesion. The present invention may include, for example, the following embodiments. 10 [0009] [I] An alloyed hot-dip galvanized steel sheet, which is a steel sheet comprising, in mass%, C: from 0.10 to 0.4%, Si: from 0.01 to 0.5%, Mn: from 1.0 to 3.0%, 0: 0.006% or less, P: 0.04% or less, S: 0.01% or less, Al: from 0.1 to 3.0%, and 20 N: 0.01% or less, with the balance being Fe and unavoidable impurities, wherein the structure of the steel sheet further comprises, in terms of volume fraction, 40% or more of the total content of bainite and martensite, from 8 to 25 60% of retained austenite, and less than 40% of ferrite, with the balance being an unavoidable structure, and alloying hot-dip galvanization is applied to the steel sheet surface, and wherein the total thickness of the thickness Tyl of 30 T1 layer and the thickness Ty of r layer in the alloyed hot-dip galvanized layer is 2 pm or less and the ratio (Tyl/Ty) of thickness between T1 phase and r phase is 1 or less. [OOlO] 3 5 [2] The alloyed hot-dip galvanized steel sheet according to 111, wherein the ratio ( (T<+TG) / (Tyl+Ty) 1 of the total thickness of thickness T< of < layer and thickness TF of 6 layer in the alloyed hot-dip galvanized layer to the total thickness of T1 layer and r layer is from 1.5 to 90. 5 [3] The alloyed hot-dip galvanized steel sheet according to [I] or [2], wherein the steel sheet further comprises one member or two or more members of, in mass%, Cr: from 0.05 to 1.0%, Ni: from 0.05 to 1.0%, Cu: from 0.05 to 1.0%, Nb: from 0.005 to 0.3%, Ti: from 0.005 to 0.3%, V: from 0.005 to 0.5%, B: from 0.0001 to 0.01%, Ca: from 0.0005 to 0.04%, Mg: from 0.0005 to 0.04%, La: from 0.0005 to 0.04%, Ce: from 0.0005 to 0.04%, and Y: from 0.0005 to 0.04%. 20 [4] A process for producing an alloyed hot-dip galvanized steel sheet, comprising: heating a steel material comprising, in mass%, C: from 0.10 to 0.4%, Si: from 0.01 to 0.5%, Mn: from 1.0 to 3.0%, 0: 0.006% or less, P: 0.04% or less, S: 0.01% or less, Al: from 0.1 to 3.0%, and N: 0.01% or less, with the balance being Fe and unavoidable impurities, at 1,100 to 1,300°C and then subjecting the steel sheet to a hot rolling treatment at a finish rolling temperature of Ar3 temperature or more; taking up the hot-rolled steel sheet at a take-up 3 5 temperature of 700°C or less and then cold-rolling the steel sheet; annealing the cold-rolled steel sheet at a maximum heating temperature of 750 to 900°C; cooling the annealed steel sheet to a plating bath immersion temperature at a cooling rate of 3 to 200°C/sec 5 in the range of 500 to 750°C and then holding the steel sheet at 350 to 500°C for 10 to 1,000 seconds; performing a plating treatment by immersing the steel sheet in a hot-dip galvanizing bath having an A1 concentration WA~an d an Fe concentration WFe satisfying, 10 in mass%, the following relational expressions (1) and (2), at a steel sheet temperature ranging, on immersion in a plating bath, from a temperature 40°C lower than the hot-dip galvanizing bath temperature to a temperature 50°C higher than the hot-dip galvanizing bath temperature, in 15 a nitrogen atmosphere having a nitrogen content of 95 mass% or more, in which the logarithm log(PHzo/PHz) value of the ratio between hydrogen partial pressure PH2 and water vapor partial pressure PHZO is from -5 to -2: O.O~90; C: a tensile strength of 980 Mpa or more and 1.5<[ (T<+T6) / (Tyl+Ty) }<90; and 2 5 D: a tensile strength of less than 980 Mpa and 1.55{ (T<+TF) / (Tyl+Ty) }