[0001]The present invention, when extracting metal compound particles etched in the metal material a metal material in an electrolytic solution, the extraction method of the metal compound particles used an electrolyte comprising an agent to capture a specific metal, the metal method for analyzing compound particles, and related to the electrolyte.
BACKGROUND
[0002]
　Metallic material, in particular, steel materials, the trace additive elements and various heat treatment, the type of inclusions and precipitated phases present in the material matrix, the shape such as an aspect ratio, by controlling the size, etc., required for the steel material it has been widely practiced to control the strength and characteristics.
　Accordingly, observation and the inclusions and / or precipitation phase, measuring the components, the amount is in conducting analysis of the quality control and manufacturing processes of the steel material, it has important implications.
[0003]
　In order to perform the observation of inclusions and precipitated phases by SEM or the like, it is necessary to expose the viewing surface of the inclusions and precipitated phases in the state of buried in the matrix, by a conventional electrolysis in various electrolyte solution the inclusions and precipitation phase is exposed to the sample surface, and an observable state.
[0004]
　Recently, advances in manufacturing techniques for steel materials, with the type of inclusions and precipitated phases are diverse, and they have also finely dispersed, upon observation, as well as selectively dissolving only the matrix (Fe), interposed For the goods and precipitated phase, they even fine particles, held in securely viewing surface, an electrolyte that does not dissolve is determined.
[0005]
　Further, in the case of identification and quantitative analysis of these inclusions and precipitated phases, similarly to dissolve the matrix steel sample in an electrolytic solution, to recover the inclusions and precipitated phases as the electrolytic residue, identification and this it has been performed to quantitatively analyze.
[0006]
　In the case of the quantitative analysis, electrolysis with only efficiently electrolyzing the matrix portion of the steel material holds dissolved in reliably electrolyte solution in Fe content, a portion corresponding to the other inclusions and precipitated phases it is required that can reliably collected as a residue.
[0007]
　Patent Document 1, an electrolyte composition for the steel samples, inclusions and using the same analysis method of precipitates is described.
　The electrolyte composition is that the conventional electrolytic solution were often acidic, by alkaline triethanolamine is added, even fine inclusions and precipitated phases, dissolved It becomes hard, particles of these inclusions and precipitates easily remains on the steel sample surface, after drying removed the steel sample from the electrolyte, thereby enabling the observation and analysis by SEM, etc. as it is.
[0008]
　Further, Patent Document 2, an extraction for a non-aqueous solvent electrolyte of inclusions and precipitates in the steel sample, the invention relates to electrowinning method for steel samples using the same are disclosed.
　The electrolyte, and maleic acid, and tetramethylammonium chloride, are those containing methanol at a predetermined ratio, and an electrolytic solution having excellent ability to electrolysis a large number of steel samples at a time are included in the liquid maleic anhydride, having the characteristics to generate an iron complex, to prevent precipitation such as Fe hydroxides.
[0009]
　On the other hand, Patent Document 3 is not a technique directed to steel samples, the arsenic impurity elements in the copper containing minerals to sedimentation and copper ions, as a floating inhibitors of arsenic minerals, triethylenetetramine ( TETA) and a technique of using ethylenediaminetetraacetic acid (EDTA) is disclosed.
[0010]
　Inclusions and precipitation phase in the steel sample to be observed in situ in SEM or the like, a sample is electrolyzed, it holds the Fe component constituting the matrix, the electrolytic solution in Fe ion chelator, inclusions Ya precipitated phase is electrolytically to remain on the sample surface.
　On the other hand, if the quantitative analysis of inclusions and precipitated phases, the Fe content of the matrix holds the electrolytic solution by the chelating agent, using an electrolytic solution which does not dissolve the inclusions and precipitation phase separated from the sample by electrolysis , to recover them as electrolytic residue and identification and quantitative analysis of residue.
　Thus, for the electrolyte for the purpose of residue collected for identification and quantitative analysis of the inclusions and precipitation phase, and focus is placed on being able to maintain the dissolved state of Fe content as chelate complex in the electrolyte, the electrolyte for such as contamination for inclusions and precipitated phase in the liquid, special consideration has not been made.
CITATION
Patent Document
[0011]
Patent Document 1: JP 2002-303620 Patent Publication
Patent Document 2: JP 2000-137015 Patent Publication
Patent Document 3: JP 2011-156521 JP
Summary of the Invention
Problems that the Invention is to Solve
[0012]
　During metal compound analysis in steel by electrolytic etching or the like in the conventional non-aqueous solvent electrolyte solution, fine particles of inclusions and precipitated phases, in particular, various metal compounds, among them the surface layer of MnS, other than electrolysis operation was sometimes than content measured by means unexplained phenomenon high concentration of CuS is observed is observed. Therefore, there is possible to detect the MnS particles though as CuS (Artifact CuS).
[0013]
　The present inventors have, for the cause, a study result, electrolysis operation in detail, solubility product K in the electrolyte sp small metal ions of (Cu 2+ when) is generated at the surface of the metal sulfide (MnS), big metal ion solubility product Ksp (Mn 2+ ) is, the solubility product Ksp of small metal ions (Cu 2+ was found to be substituted (exchange) in). The substitution of metal ions in such sulfide surface, at room temperature and atmospheric pressure, moreover have found that to proceed easily in aqueous solutions and non-aqueous solvent.
[0014]
　As a result, in the steel samples, the presence to have inclusions and precipitated phases originally as MnS, as long as observation of the surface, will be observed as CuS, also on the surface of MnS, Cu ions in the electrolyte CuS due to the, by replacing several tens of nm in thickness (1 ~ 100nm) MnS, be subjected to mass spectrometry from the residue, in the case of fine particles, and occupy a substantial portion of the volume of CuS since, it had become an accurate quantification is impossible.
[0015]
　Above has been described in the case of attack on the MnS surface by Cu (substitution phenomenon of Mn atoms and Cu atoms of MnS surface), it can be estimated that express a similar phenomenon in the metal other than Cu. That is, the substitution of metal ions on the surface metal compound, the solubility product K sp magnitude difference corresponding to (10 digits (10 10 when there are) More particularly, the solubility product K sp pK of two compounds having different sp when the difference (sometimes hereinafter referred to as delta) is about 10 or more, pK sp large (solubility product K sp small) compound and pK sp substitution with a small compound (solubility greater product) can be estimated easily be advanced.
The above conditions can be expressed by the following equation.
Delta = pK sp [compound (K sp less ones of)] - pK sp [compound (K sp larger of)]
　= (- log 10 K sp [compound (K sp less ones of)]) - (- log 10 K sp [compound (K sp large ones)])
　≧ 10
, where the solubility product K of certain compounds sp is K sp represents the [compound], pK sp [compound] = - log 10 K sp [compound] and represent.
[0016]
　Indeed, the present inventors have conducted simulations to act Ag in MnS, Ag is to attack the MnS, together expel the ionized in the electrolytic solution Mn, itself, Ag in MnS surface 2 S it remains as it was confirmed. Here, Ag 2 S and MnS solubility product (or pK sp Comparing), Ag 2 solubility product K of S sp small (pK sp is large), the solubility product K of MnS sp is large (pK sp is smaller ). Ag 2 solubility product K S and MnS sp difference is 37 digits, pK sp is the difference Δ of a 36.6. Expressed in equation or less.
= PK delta sp [Ag 2 S] -pK sp [MnS]
　= 50.1-13.5
　= 36.6 ≧ 10
[0017]
　Therefore, an object of the present invention to provide or less.
- the fine metal particles (inclusions, precipitates) of a metal material by electrolytic etching method or the like in solvent electrolyte in the extraction and analysis, without changing the conventional extraction and analysis methods large, fine metal particles of Cu ions suppressing resurfacing of an object to prevent the formation of such Artifact (fictitious) CuS.
Especially metal sulfide (MnS, FeS, etc.) focused on, and an object thereof is to prevent the formation of such Artifact (fictitious) CuS.
Means for Solving the Problems
[0018]
　The present inventors, the technique for solving the above problems, intensive studies.
　As a result, in a solvent system electrolytic solution, if the presence of a metal (attack metals) forming the Artifact (fictitious) metal sulfide, substitution phenomenon from finding that not expressed, to supplement such attack metal It led feelings. That is, the solvent-based electrolyte solution, by adding Artifact (fictitious) metal to form the metal sulfide (attack metals) selectively captured to drug (chelating agent), free attack metals in the electrolyte There was decreased, and conceived that Artifact (fictitious) metal sulfide is not produced.
[0019]
　For example, the Cu ions dissolved out from the steel sample and the like, by Cu ion chelator, and held in the electrolytic solution, it does not attack the MnS surface observation for steel sample surface, or identification and quantification of inclusions and precipitated phases also in electrolysis operations for analysis by Cu chelating agent in the electrolyte solution in the same manner, the Cu ions as a chelate complex, by maintaining in the electrolyte solution, the residue for quantitative analysis made from inclusions and precipitated phases to, by so CuS is not mixed, the inclusions and precipitated phase of the steel sample for surface observation can be observed while the original form, also in electrolytic residue is analyzed , free of CuS and the like derived from the Cu ions eluted from the matrix or the like of the sample originally, it only element due to inclusions and precipitation phase which contained the steel samples, can be correctly identified and quantified Found it was.
[0020]
　The present invention has been made based on the above findings, its gist the following.
(1) a metal material is etched in an electrolytic solution, a method of extracting the metal compound particles in the metal material,
a metal compound M ' x' A 'y the solubility product K sp [M' x ' A y' ] and then,
extracted target metal compound M included in the metal material in x a y the solubility product K sp [M x a y When,
complexes containing a metal M 'which Δ is defined by the following equation becomes 10 or more the use of the electrolytic solution comprising an agent which forms the features a, method for extracting metal compound particles.

= PK delta sp [M ' x' A y ' ] -pK sp [M x A
y ] = (- log 10 K sp [M' x ' A y' ]) - (- log 10 K sp [M x A y ])

here, M and M 'are different metal elements, a is M or M' is a single atom or group to form a compound, x, x ', y, y' is M, M ' represents the composition ratio of the compound depends on the valence of a, said solubility product K sp is the value at 25 ° C. in an aqueous solution
[0021]
(2) method for extracting metal compound particles according to (1), wherein the electrolyte is a non-aqueous solvent electrolyte.
[0022]
(3) the extraction target metal compound M x A y extracting method of MnS or the (1), characterized in that one or two of FeS or (2) the metal compound particles described.
[0023]
(4) the metal compound M ' x' A 'y the metal of M' is, Hg, Ag, Cu, Pb , Cd, Co, characterized in that at least one of Zn, and Ni (1) method of extracting the metal compound particles according to any one of the - (3).
[0024]
(5) wherein the agent is characterized in that it comprises a crown ether, the (1) to the extraction method of the metal compound particles according to any one of (4).
[0025]
(6) wherein the agent is polyethylene amines, characterized in that it comprises ethylenediaminetetraacetic acid, any one of a cyclohexane diamine tetraacetic acid or two or more, any of the above (1) to (5) method of extracting the metal compound particles crab according.
[0026]
(7) The agent is characterized in that it comprises triethylenetetramine, method of extracting the metal compound particles according to (6).
[0027]
(8), wherein the metallic material is a steel material, method of extracting the metal compound particles according to any one of the above (1) to (7).
[0028]
(9) said through an electrolytic solution after etching the filter, when extracting metal compound particles as collected residue, above, wherein said filter is a polytetrafluoroethylene-made filter (1) - method of extracting the metal compound particles according to any one of (8).
[0029]
(10) In (1) to (9) any method for analyzing metal compound particles, characterized by analyzing the metal compound particles extracted by the extraction method of the metal compound particles according to the.
[0030]
(11) The metal material is etched, a electrolyte solution used to extract the metal compound particles in the metal material,
a metal compound M ' x' A 'y the solubility product K sp [M' x ' A y ' ] and then,
extracted target metal compound M included in the metal material in x a y the solubility product K sp [M x a y When,
metal M Δ is defined by the following equation becomes 10 or more' of the comprising that it comprises an agent to form a complex, and wherein the electrolytic solution.

= PK delta sp [M ' x' A y ' ] -pK sp [M x A
y ] = (- log 10 K sp [M' x ' A y' ]) - (- log 10 K sp [M x A y ])
here, M and M 'are different metal elements, a is M or M' is a single atom or group to form a compound, x, x ', y, y' is M, M ' represents the composition ratio of the compound depends on the valence of a, said solubility product K sp is the value at 25 ° C. in an aqueous solution
[0031]
(12) electrolytic solution according to the above (11), which is a non-aqueous solvent system.
[0032]
(13) the extracted target metal compound M x A y , wherein the is one or two of MnS or FeS, electrolyte solution according to the above (11) or (12).
[0033]
(14) the metal compound M ' x' A 'y metal M' is, for Hg, Ag, Cu, Pb, Cd, Co, characterized in that at least one of Zn, and Ni, the (11 ) electrolyte solution according to any one of - (13).
[0034]
(15) wherein the agent is characterized in that it comprises a crown ether, the electrolytic solution according to any one of the above (11) to (14).
[0035]
(16) wherein the agent is polyethylene amines, characterized in that it comprises ethylenediaminetetraacetic acid, any one of a cyclohexane diamine tetraacetic acid or two or more, any of the above (11) - (15) electrolyte of crab described.
[0036]
(17) wherein the agent is characterized by comprising triethylenetetramine, electrolyte solution according to the above (16).
[0037]
(18), wherein the metallic material is a steel material, the above-mentioned (11) to the electrolytic solution according to any one of (17).
(19) The non-aqueous solvents are methanol, characterized in that it comprises at least one ethanol (11) electrolyte solution according to any one of - (18).
Effect of the invention
[0038]
According-to the present invention, the surface analysis of the extracted metal particles, reality disappears be misidentified as CuS particulate is MnS and FeS, true form (size, components) of the metal sulfide can know news can also be accurately determined amount of metal sulfide in the steel material.
According-to the present invention, except that it is possible to observe in nature present are the components and form steel sample inclusions or precipitates equality exposed on the steel sheet sample surface by electrolytic operation, the analysis of electrolyte residue when quantitative analysis of inclusions and precipitation phase component, without being affected such as Cu contamination from the electrolyte, it is possible to correctly quantitative analysis, structure observation and the steel samples, inclusions in the steel sample or in which it contributes to greatly improve the accuracy of the identification and quantitative analysis of the precipitate phase.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039]
It illustrates an example of a pictorial view of an electrolytic apparatus using FIG. 1 electrolytic solution according to the present invention.
It is a graph showing the FIG. 2] SEM photographs and element concentration of inclusions near the electrolytic polished steel sample.
3 is a graph showing the SEM photograph and the element concentration of inclusions near the specular polished steel sample.
4 is a graph showing the analysis results of the electrolytic residue steel samples.
5 is a graph showing the SEM photograph and the element concentration of inclusions near the specular polished steel sample.
DESCRIPTION OF THE INVENTION
[0040]
　The present invention, by etching a metal material in an electrolytic solution, a method of extracting the metal compound particles in the metal material,
a metal compound M ' x' A 'y the solubility product K sp [M' x ' A y' and,
extracting target metal compound M included in the metal material in x a y the solubility product K sp [M x a y When,
comprising a metal M 'which Δ is defined by the following equation becomes 10 or more the use of the electrolytic solution comprising an agent that forms a complex, and wherein the extraction method of the metal compound particles, is provided.

= PK delta sp [M ' x' A y ' ] -pK sp [M x A
y ] = (- log 10 K sp [M' x ' A y' ]) - (- log 10 K sp [M x A y ])
here, M and M 'are different metal elements, a is M or M' is a single atom or group to form a compound, x, x ', y, y' is M, M ' represents the composition ratio of the compound depends on the valence of a, said solubility product K sp is the value at 25 ° C. in an aqueous solution.
[0041]
　In the present invention, to extract the metal compound particles in the metal material. That is, by etching the metal material in an electrolytic solution, to selectively dissolve the matrix (Fe, etc.), to expose the metal compound particles of inclusions and precipitation phase etc. contained in the metal material on the sample surface. This allows the metal compound particles in the observable state.
　As an extraction method of the fine particles of the metal in the sample, for example, acid decomposition method to dissolve the iron matrix of the steel sample in an acid solution, halogen dissolution to dissolve iron matrix steel samples with iodine methanol mixed solution or a bromine-methanol mixed solution Law, non-aqueous solvent constant current electrolysis, or, non-aqueous solvent controlled potential electrolysis (SPEED: Selective potentiostatic Etching by electrolytic Dissolution method) method, or the like. Of these, SPEED method using a non-aqueous solvent, when the fine particles are dispersed in a solvent, unlikely to occur change in the composition and size, is suitable because it can extract also stable in unstable particles. With the present embodiment, with reference to FIG. 1, a non-aqueous solvent system controlled potential electrolysis by (SPEED method) as an example of the evaluation method of the particulates in the steel material, but will be described, the method of extraction in the present invention not limited to SPEED method, also, the metal material is not limited to steel materials.
[0042]
　Initially, the metal sample 4, for example, processed to dimensions of 20 mm × 40 mm × 2 mm, an oxide film such as a surface layer such as scale is removed by chemical polishing or mechanical polishing, etc., it should issue the metal layer . Conversely, when analyzing particles contained in the oxide film layer, leaving intact form.
[0043]
　Next, the metal sample, electrolysis using the SPEED method. Specifically, it meets the electrolytic solution 9 to the electrolytic cell 10, by immersing the metal sample 4 therein, the reference electrode 7 is brought into contact with the metal sample 4. Connecting the platinum electrode 6 and the metal sample 4 in the electrolytic device 8. Generally use of the above electrolysis method, compared to the electrolysis potential of the metal portion serving as the matrix of the metal sample 4, the electrolytic potential of the steel in the fine particles such as precipitates with high electrolysis potential. Therefore, by using the electrolytic apparatus 8 was dissolved matrix metal sample 4, and between the electrolyte potential does not dissolve the fine particles of the precipitate or the like, by setting the voltage, it is possible to selectively dissolve only matrix to become. The Fe electrolytic eluted sample surface of the surface matrix portions, inclusions or precipitation phase 5 is raised in a state suitable for observation by SEM or the like. Moreover, continued electrolysis, the inclusions and precipitation phase is disengaged from the surface of the sample, recovered as electrolytic residue 11, and filtered off from the electrolyte, it may be subjected to identification and quantitative analysis.
[0044]
　Electrolytic solution for a metal material according to the present invention, i.e., or electrolysis Fe matrix of the surface in order to observe the inclusions and precipitation phase, in order to quantitatively analyze the inclusions and precipitated phases, electrolyze Fe matrix, electrolyte for use in electrolytic for recovering residues, preferably,
　(1) complexing agent for Fe ions,
　(2) electrolyte order to ensure conductivity to the electrolyte,
　of Fe or the like which is (3) formed solvent, for holding the complex in the liquid
containing.
[0045]
　The complexing agent for Fe ions, acetylacetonate, maleic anhydride, maleic acid, triethanolamine, salicylic acid, may select one or more from among the methyl salicylate.
[0046]
　The electrolyte, tetramethylammonium chloride (TMAC), sodium chloride (NaCl), it is possible to select one or more from among lithium chloride (LiCl).
[0047]
　Solvents, and various complexing agents, must be one that can hold a complex thereof with Fe in solution, or may be a non-aqueous solvent. To a relatively low electrolytic voltage in aqueous electrolyte solution (e.g., -300mV or less) even various precipitates to degrade, non-aqueous solvent electrolyte is wide stable electrolysis region, superalloys, high alloy, stainless it can be applied to almost any steel material to the carbon steel from. When using a non-aqueous solvent electrolyte, primarily, the dissolution of the matrix, dissolved in the Fe ions and the chelating agent is only (complexation) reaction occurs, inclusions or precipitation phase 5 without dissolving, it is possible to perform a three-dimensional observation and analysis in the "in situ" state on the base material. As the non-aqueous solvent, proceeds smoothly electrolysis, moreover, a compound that dissolves and a complexing organic compound capable supporting electrolyte is suitable, for example, lower alcohols, for example, be methanol, ethanol, or isopropyl alcohol can. Methanol or ethanol, or may be selected mixtures thereof. Also it is used as long as it is a solvent which have a how these alcohols with comparable more polar (dipole moment, etc.).
[0048]
　The conventional constant-potential electrolytic method, an electrolytic solution, for example, 10 mass% acetylacetone (hereinafter referred to as "AA") -1 mass% tetramethylammonium chloride (hereinafter referred to as "TMAC") - methanol, or 10 wt% maleic anhydride -2 wt% TMAC- methanol solution is used. In these electrolyte solutions, electrolyte eluted Fe generates a complex, resulting Fe complex because preferable from the viewpoint that dissolves in the electrolyte, are widely used.
[0049]
　Metals other than the matrix (Fe) in the electrolytic solution, although relatively if Hisure matrix (Fe) is slight, it may be eluted. Its solubility product K elution metal sp is small (in other words, pK sp (= -log 10 K sp ) is large), inclusions or precipitated phases 5 and electrolyte residue 11 is the solubility product K sp large (pK sp is smaller ) if it contains metal of the metal compound, the surface of the metal compound, the solubility product K sp large (pK sp is small) metal ions (e.g. Mn 2+ ) is, the solubility product K sp small (pK sp is large) metal ions (e.g. Cu 2+ to be replaced) (exchange), the present inventor has discovered. This substitution solubility product K sp difference of 10 digits (10 10 when there is a magnitude difference) than about, more specifically, the solubility product K sp pK of two compounds having different sp difference Δ of about 10 or more when it is considered that proceeds easily. Solubility product K sp difference of 20 digits (10 20 when there is a magnitude difference) than about, and more particularly, pK sp when the difference Δ is about 20 or more, substitution is considered to more readily proceeds.
[0050]
　Table 1, the solubility product K sulfide at 25 ° C. in an aqueous solution sp and, pK between sulfide sp (= -log 10 K sp indicates a difference Δ in). In the table, the frame of the double line (or dark gray frame) is pK sp is the combination of sulfide difference Δ is 22 or more, expected exchange reaction readily or proceed in seconds in those combinations It is. Expressed in simplified manner symbol, the expectation of the exchange reaction (prediction) is expressed as ◎. Thick lines (or light gray box) are pK sp is a combination of the difference Δ sulfide is less than 10 or more 22, it is possible to it takes from a few minutes to several hours units are expected to exchange reaction proceeds that. Expressed in simplified manner symbol, the expectation of the exchange reaction (prediction) is expressed as ○ ~ △. Thin line frame (or white frame) is pK sp is the combination of sulfide difference Δ is less than 10, the exchange reaction is a combination thereof are expected to hardly proceed. Expressed in simplified manner symbol, the expectation of the exchange reaction (prediction) is expressed as △ ~ ×.
　Regarding the solubility product of sulfide, a sulfide of the same element by crystal form such also, there is shown a different solubility product. In Table 1, pK sp is listed sulfide having a crystal form such difference Δ is small. This, pK sp be in a form difference Δ increases, pK of the sulfide to be sp difference Δ becomes 10 or more, it is considered that exchange reaction proceeds.
[0051]
[Table 1]

[0052]
　The above solubility product K sp but is a value in aqueous solution, it is estimated that there is the same tendency even nonaqueous solvent such as methanol in the same polar solvent.
[0053]
　For example, if there is MnS in the steel sample surface or electrolyte residue, sulfides Cu ions eluted in the electrolyte solution, pK of the MnS sp for the difference Δ is 22.6, the MnS and attack, with expel the electrolyte to ionize the Mn, itself, remains as CuS the MnS surface. That is, in a Cu-containing steel sample, originally inclusions were present as MnS and precipitation phase, as long as observing the surface, will be observed as CuS. Further, the surface of MnS, CuS due to Cu ions in the electrolyte, by replacing the thickness of several tens of nm (1 ~ 100nm) MnS, be subjected to mass spectrometry from the residue, if fine particles the, since the occupying a substantial portion of the volume of CuS, accurate quantification becomes possible. The phenomenon of metal such surface vicinity is replaced, in this specification, sometimes referred to as Artifact (fictitious).
[0054]
　Further, sulfides Ag ions, pK of the MnS sp for the difference Δ is 36.6, and attack the MnS, together with ionized Mn expelled into the electrolytic solution, itself, Ag on MnS surface 2 remains as S. This is confirmed in Figure 5 obtained by the following procedure.
· MnS was prepared confirmed steel sample that contains as inclusions, in order to remove surface impurities, subjected to a pre-polished.
- include sulfides are conventionally known inclusions can recovered as a residue 4 wt% methyl salicylate + 1% by mass salicylic acid + 1% by mass tetramethylammonium chloride (TMAC), the electrolyte solvent is methanol (4% MS ) is prepared.
- the steel sample performing electrolysis in the electrolytic solution.
- After the end of electrolysis, mixed dropwise Ag ion solution in the electrolyte.
· Ag ion solution before and after the dropwise addition, the steel samples electrolytic surface, to observe and measure the surface element density by EDS scanning electron microscope (SEM).
- Figure 5 is of a post-Ag ions dropping, the top left image is an SEM observation image, the upper right image SEM observation image, which shows superimposed charts Ag concentration measured by the EDS, the bottom left image There is limited to showing overlapping charts Mn concentration, in which the lower right image showed overlapping charts S concentration.
- In addition, as a matter of course, in front of Ag ions dropping, the presence of Ag was observed.
[0055]
　From the chart of the element concentration of 5, only the surface portion of the MnS particles Ag 2 it is confirmed substituted with S. The height of each element in the chart (concentration) is relative, the following can be read. Specifically, in a portion of the inclusion particles, the value of the graph of Mn and S has increased to a mountain type, it is inclusion particles, containing Mn and S, that is, specifically, a main component of MnS it is particles is confirmed. Ag is increased concentration at the end of the inclusion particles, it is confirmed that Ag is concentrated at the surface of the inclusion particles. Further, in the central portion of the inclusion particles, the concentration of Ag is not Takamara, since higher concentrations of Mn and S, it is confirmed that only the surface of the MnS is replaced with Ag.
[0056]
　The present inventors have found that in a method for extracting a metal compound particles in the metal material, by using a specific electrolyte solution, free attack metals in the electrolyte is reduced, that can prevent Artifact (fictitious) It found new. Specific electrolyte, metal compound M ' x' A 'y comprises an agent which forms a complex containing a metal (attack metal) M', wherein the metal compound M ' x' A y ' solubility product the K sp [M ' x' a y ' ] and,
extracted target metal compound M contained in the metallic material x a y the solubility product K sp [M x a y When],
delta = pK sp [M' x ' A y' ] -pK sp [M x A
y ] = (- log 10 K sp [M ' x' A y ' ]) - (- log 10 K sp [M x A y ])
≧ 10
is .
Here, M and M 'are different metal elements, A is M or M' is a single atom or group to form a compound, x, x ', y, y' is M, M ', A represents a composition ratio of the compound depends on the valence, the solubility product K sp is the value at 25 ° C. in an aqueous solution.
[0057]
　Artifact (constructive) as prone attack metal M 'of, the content and the solubility product K sp of low, in other words pK sp Cu from a height of is remarkable. Cu is, pK against Cu compounds sp easily attacked the difference Δ is MnS and FeS surface is approximately 20, may result in Artifact (fictitious). However, attack by Artifact (onomatopoeic) or attack metal M 'is pK sp as the difference Δ is large, considered likely to occur, subject of the present invention is not limited to the combination of Cu and MnS and FeS. Specifically, large pK sp metal compound having an M ' x' A 'y metal M' is well Hg, Ag, Cu, Pb, Cd, Co, be at least one of Zn, and Ni , these can be a attack metal M '. Attack metal M 'is mainly, metal M contained in the steel material in the sample' considered or compounds thereof are those eluted in the electrolyte solution. However, the electrolytic solution or the electrolytic device may be reused, 'may or compounds are present, which attack the metal M' metal M in the reused electrolyte or electrolytic device sometimes becomes . Further, in case of electrowinning operations, metal M 'or a compound is mixed in the electrolytic solution as contaminants, attack the metal M' may be a.
M 'is, Hg, Ag, Cu, Pb , Cd, Co, Zn, and may be at least one of Ni, a metal element different from M. A is a single atom or group forming a M or M 'and the compound, C, N, H, S, O, one or more atoms independently selected from the group consisting of atoms of P and F it may also include a. Hg, Ag, Cu, Pb, Cd, Co, and sulfides of Zn, and Ni, pK of the MnS sp difference Δ of 10 or more. In particular, Hg, Ag, and sulfides of Cu, pK of the MnS sp difference Δ of 20 or more. PK
　of extraction target metal compound MxAy and attack metal compound M'x'Ay ' sp when the difference Δ of about 10, Artifact (fictitious) can occur in a few hours. Actual electrowinning analysis is often carried out on the order of a few hours. Therefore, pK sp combinations difference Δ of about 10 is likely to affect the analysis. In the present invention, pK sp difference Δ has defined as 10 or more, it is possible to suppress the Artifact (fictitious) which may occur when the. PK
　of extraction target metal compound MxAy and attack metal compound M'x'Ay ' sp as the difference Δ is large, Artifact (fictitious) can occur easily or quickly. In the present invention, pK sp can select a combination of MxAy difference Δ is large and M'x'Ay ', whereby it is possible to suppress may occur easily or quickly Artifact (fictitious), preferred. In this regard, M'x'Ay 'pK a sp [M'x'Ay'] is, pK of extraction target metal compound MxAy sp compared to [MxAy], it may be preferable 11 or more large, large 12 or more more preferably, more preferably 13 or more large, more preferably 14 or more larger, more preferably greater than 15, more preferably 16 or more larger, more preferably 17 or more large, 18 or more greater and even more preferably, more preferably 19 or more large, more preferably 20 or more large, it is preferably 21 or more large, it is more preferably 22 or more large, more preferably 23 or more larger, more preferably greater than 24, 25 more preferably greater than, more preferably it is 26 or more large Ku, is more preferably 27 or more large, more preferably 28 or more large, more preferably 29 or more large, more preferably greater than 30, it is preferably 31 or more large, that more than 32 large More preferably, more preferably 33 or more large, more preferably 34 or more larger, more preferably greater than 35, more preferably 36 or more large, more preferably 37 or more large, more preferably 38 or more large, 39 or more more preferably greater, more preferably greater than 40.
　Incidentally, solubility product K sp but is a value in aqueous solution, as shown in Table 2, a non-aqueous solvent K even when a (lower alcohol) sp obtained from the pK sp (-log 10 K sp difference) delta There more than 10, the reaction that is observed is confirmed. Specifically, it was subjected to the following confirmation test.
And extracting the object as a sample containing, two steel containing MnS (as the particle size of MnS is not less than 1 [mu] m, and those having a particle size of 100 ~ 150 nm) was prepared, was mirror polished on their surface .
- 'As + ions, Ag, Cu, Pb, Co , Zn, a metal ion concentration of Ni, 6 kinds of atomic absorption spectrometry standard solution for each 1000 [mu] g / ml (M' attack metal M was prepared + solution). The M 'solution 0.1ml was mixed with methanol 0.3ml a non-aqueous solvent.
- The mixture is coated on the steel surface was confirmed changes in the steel surface.
Those coated with a mixture containing Ag and Cu, the surface of the steel material is changed to black within 5 minutes of application. Those coated with a mixture containing Pb, the surface of the steel material is changed to black in about 10 minutes from the application. Co, Zn, obtained by coating a mixed solution containing Ni, the surface of the steel material is changed to black in about 20 minutes from the application.
- In addition, it was subjected to SEM and EDS observed for was discolored steel, substitution of Mn and the attack metal M 'on the surface of any MnS particles (i.e., Artifact (onomatopoeic)) it was confirmed that occurs It was.
Therefore, the scope of the present invention, the solubility product K sp but is an indication of an aqueous solution, it is possible to apply the non-aqueous solution, wherein solubility product K in sp it shows the same tendency as in an aqueous solution There are estimated.
Further, pK sp as the difference Δ is large, substituted (Artifact (onomatopoeic)) reaction was also confirmed fast that. On the other hand, pK sp even small differences Δ of, although relatively reaction rate becomes slow, steady substituted (Artifact (onomatopoeic)) reaction was also confirmed to proceed. Electrolytic extraction analysis of steel are often performed in the order of a few hours. For example, there is a time soak the sample in the electrolytic solution, even if planned in about 2 hours, also be further extended about 1 hour. pK sp If the difference Δ is using Ni-containing solution and MnS to be 10, was observed color change in about 20 minutes. That, pK sp difference Δ is the 10 or more, substituted (Artifact (onomatopoeic)) reaction, that can be problematic is confirmed.
　In this connection, in addition to the confirmation test of the attack metal M '+ solution and triethylenetetramine as further complexing agent in a mixture of methanol (TETA) plus 0.1 ml (complexing agent additive liquid ) was prepared, it was carried out it is also the case that was applied to the mirror-finished steel observation. If you make a complexing agent additive solution, several hours later discoloration of the steel surface is not observed, a good mirror-polished state is held. Even in SEM and EDS observation, Artifact (fictitious) was not confirmed.
[0058]
[Table 2]

[0059]
　As an agent for forming a complex containing such attack metal M ', it is available crown ethers. Crown (Crown) ether is a cyclic polyether (which ether units led some), it is possible to change the size of the hole of the annular. Therefore, the attack metal species M 'depending on, ready crown ethers having suitable holes, whereby the attack metal species M' can selectively capture only.
[0060]
　Agent to form a complex including attack metal M 'is selected from the group consisting of polyethylene amines, ethylenediaminetetraacetic acid, one kind or may contain two or more of cyclohexane diamine tetraacetic acid. These act as a chelating agent to trap the attack metal M '. As polyethylene amines, triethylenetetramine (TETA), penicillamine, pentaethylenehexamine and the like. In particular, chelating agents such as triethylene tetramine has a high selectivity for Cu ions and Ni ions, attack the metal M 'is in the case of Cu and Ni and the like, are exhibited particularly high trapping effect.
Table 3 attack Cu or Ni as the metal M 'when captured by various chelating agents, complexes of the stability constant (Log 10 K d shows a). More stability constant is high, the captured the attack metal, considered less likely to again liberated, preferred. Compound M ' x' A y , especially inhibiting the formation of CuS, as an agent for forming a complex comprising an attack metal M ', those stability constant of 10 or more, preferably one of the 12 or more, more preferably 14 more than that, more preferably of 16 or more, more preferably 18 or more of, and more preferably of 20 or more, may be selected. In general, compounds M 'should suppress generation x' A y the solubility product K sp [M ' x' A 'y When, pK] sp [M' x ' A y' ] (= - Log 10 K sp [M ' x' a y ' ]) and Log K d the difference between, pK sp [M' x ' a y' ] -log K d is, of less than 26, preferably of less than 24, more preferably less than 22 ones, more preferably of less than 20, more preferably of less than 18, more preferably of less than 16, may be selected.
[0061]
[table 3]

[0062]
　Attack metal M 'is captured, attack the metal M' complex is formed. Complex attack metal M 'is maintained in a dissolved state in the above-mentioned solvent. Therefore, pK sp difference Δ is large metal compound M of x A y be present, attack the metal M 'is a metal compound M x A y replaced with a metal M on the surface (i.e., Artifact (onomatopoeic)) It can not be carried out freely. In other words, M ' x' A y ' generation of is suppressed.
[0063]
　Agent to form a complex or electrolyte containing this, may be stirred in the electrolytic bath. Thus, unreacted drug 'likely to contact with, attack the metal M' attack metal M becomes is easily captured. It means the stirring is not particularly limited, bubbling with bubble generator may be used vortex due magnetic stirrer. Or it may be formed by dropping droplets of medicament unreacted in the vicinity of the attack metal M '. As unreacted drug is easily contacted to attack the metal M ', if bubbling 100 cc / min, preferably 200 cc / min, 100 rpm if stirrer, preferably at 200 rpm, may be lower. When bubbling amount and stirrer speed is too high, resulting in problems such as peeling of the electrolyte surface of the object. Therefore, if the bubbling 600cc / min, preferably 500 cc / min, if stirrer 600 rpm, preferably may be up to 500 rpm.
　In the case where in a general electrolytic operation performs agitation of the electrolyte solution, as electrolyte flow is not in contact with the electrolyte object caused by stirring, stirring operation is performed. This is based on the idea that the electrolyte flow generated by the stirring so as not to affect the electrolytic object. In the present invention, from the viewpoint of the drug to form a complex is likely to contact the attack metal M 'or a source thereof, such electrolyte flow is in contact with the electrolyte object caused by stirring or the like, stirring or supplying the drug it may be.
　Further, nitrogen gas or helium, an inert gas such as argon may be mentioned as a gas for bubbling. Active gas such as oxygen and hydrogen, may affect the concentration of dissolved oxygen in the electrolyte, since it may affect the electrolytic object, which is not preferable.
[0064]
　Metallic material in the present invention may be a steel material. The steel material refers to a material mainly composed of iron may include a carbon traces.
[0065]
　The electrolytic solution after etching through a filter, when extracting metal compound particles as collected residue, the filter may be a tetrafluoroethylene resin filter. To identify and quantitative analysis of the inclusions and precipitated phases 5 and residue 11 for the filter to adopt straining inclusions or precipitated phases 5 and residue 11 from the electrolyte, New chestnut pore filters that are conventionally used (GE Corp.) So it is difficult to take filter out residue was dissolved damaged. In particular, when the chelating agent comprises triethylene tetramine, damage of the filter is remarkable. If tetrafluoroethylene resin filter, since the chelating agent even when containing triethylenetetramine, dissolution less damage, preferred.
[0066]
　The present invention is also provided to analyze the metal compound particles extracted by the above method. The metal compound dispersoids performs approximate composition analyzed by XRF, or may be performed elaborate composition analysis by ICP. Further, as a surface analysis method, observation by SEM, may be used elemental analysis or the like by EDS. In the course of etching, by analyzing the surface of a sample metal compound is extracted, it is also possible to observe the context in which it is the extraction of metal compounds in a time series.
[0067]
　The present invention, in the electrolyte solution, selectively held as a complex, stably dissolved in the electrolyte attack metal (Cu ions), such as to replace attacking constituents elements of inclusions and precipitated phases if a component that can maintain, in the surface observation of the sample, inclusions and precipitation phases can be observed in the form originally present in the steel samples, and in identification and quantitative analysis of inclusions and precipitation phase , and the Cu ions or the like is mixed into the electrolyte residue to be analyzed, does not reduce the identification and quantitative analysis accuracy of inclusions and precipitated phases. For example, according to the present invention, the surface analysis of the extracted metal particles, reality disappears be misidentified as CuS particulate is MnS and FeS, true form (size, components) of the metal sulfide can be known, Furthermore it is possible to also accurately grasp the content of metal sulfide in the steel material.
[0068]
　Incidentally, in the steel, Mn precipitates MnS is easily replaced by Se, and it is reported that may precipitate as MnSe, as the reason, the same NaCl type structure MnS and MnSe, the lattice constant is very it is said to be due to close. From the Periodic, S, for also Sb and Te and the adjacent group is Se and cognate be easily replaced with S of MnS, are also expected to precipitate as MnTe and MnSb. Then, MnS is, MnSe, MnTe and, or if being easily replaced MnSb, correct quantitative analysis of MnS is, MnSe, believed to also help improve the accuracy of quantitative analysis of MnTe and MnSb.
[0069]
　Further, MnSe further may result in substitution (Artifact (onomatopoeic) reactions with other selenide in. Table 4, pK between selenide at 25 ° C. in an aqueous solution resulting from the substitution or the like of MnS sp (= -log 10 K sp ) difference delta. in table showing of a double line border (or dark gray frame) is pK sp is the combination of selenide is difference delta is 22 or more, the exchange reaction is a combination thereof expressed easily or is expected to proceed in seconds. simply by the symbol, the expectation of the exchange reaction (prediction) is expressed as ◎. thick lines (or light gray box) are pK sp difference Δ is a combination of selenide is less than 10 to 22, it is possible to it takes from a few minutes to several hours units, if indicated by the. simplified manner symbols that are expected to exchange reaction proceeds, the expected exchange reaction (Prediction) is expressed as ○ ~ △. Thin line frame (or white frame) is pK sp is the combination of selenide difference Δ is less than 10, the exchange reaction is a combination thereof and hardly proceeds if indicated by the expected. simplified manner symbol, the expectation of the exchange reaction (prediction) is expressed as △ ~ ×.
[0070]
[Table 4]

[0071]
　According to the present invention, also selenides, it is possible to prevent Artifact (fictitious).
[0072]
　Furthermore by the present invention, the electrolyte used in the method of extracting the metal compound particles are also provided.
[0073]
　Electrolyte according to the present invention, as components other than the drug (Cu ion chelating agent) to selectively complement the attack metals described above (Cu ions), if necessary, also contain particles dispersant such as SDS good.
Example 1
[0074]
　Hereinafter, through examples illustrate the present invention. However, the present invention should not be construed as being limited to the following Examples.
[0075]
　The electrolyte and the electrolytic method according to the present invention, was observed of inclusions or precipitation phase in the steel samples. As a control example, it can be recovered sulfide inclusions which have been conventionally known as a residue 4 wt% methyl salicylate + 1% by mass salicylic acid + 1% by mass tetramethylammonium chloride conventional electrolyte containing (TMAC) (4% MS) using, by using the comparative example electrolyte, it was observed of inclusions or precipitation phases of the same steel sample. The electrolytic solution according to the present invention, using the electrolytic solution of triethylenetetramine (TETA) 5 vol% + 1 wt% tetramethylammonium chloride (TMAC) to (5% TETA). Incidentally, the solvent was methanol either.
[0076]
　The results are shown in Figure 2.
　Figure 2a is steel samples electrolyzed surface by the electrolyte according to the present invention, Figure 2b, the observation photograph by the scanning electron microscope steel sample electrolyte surface by using a conventional electrolytic solution, the concentration of Cu was measured by EDS It illustrates superimposed graphs. Before electrolysis, in the steel samples, to remove surface impurities, subjected to pre-polished.
　Under each of the scanning electron micrographs were Do掲those described by extracting only the Cu concentration graph.
[0077]
　Values ​​in the graph height (Cu concentration), so is relative, when the electrolyte in the electrolytic solution according to the present invention, Cu concentration in the precipitated particles and the Fe matrix portion, it can be seen no difference whereas, in the case of measuring the Cu concentration was electrolyzed in conventional electrolytic solution shown in Figure 2b, the deposited particles moiety, it can be seen that the Cu concentration is rising.
[0078]
　For steel samples used in the above Examples and Control Examples, the inventors have conducted only mirror polishing, tried and subjected to elemental analysis.
　The results are shown in Figure 3. In the figure, SEM is a scanning electron micrograph of the inclusion particles existing parts. And the particle, its vicinity, was performed elemental analysis.
　As a result, in the portion of the inclusion particles, which value in the graph of Mn and S is increased, inclusions particles containing Mn and S, that is, specifically, it was confirmed that the MnS.
　On the other hand, Cu component, a peak not observed, it was confirmed that not included in the inclusions.
[0079]
　From the results described above, using a conventional electrolytic solution, and electrolytic steel sample, when the micro analysis by observation and EDS with SEM or the like, inherently, MnS observed in the steel material, it was immersed in the electrolyte Accordingly, at least the surface of the MnS is contaminated CuS, it was found that a defect is observed as CuS occurs.
[0080]
　In contrast, by using the electrolyte solution according to the present invention, without a problem as described above occurs, MnS, so is kept in MnS, even microscopic analysis observation and EDS with SEM or the like, in a steel sample since can be observed in the presence inherently it can contribute greatly to improvement of analysis precision of the steel sample.
Example 2
[0081]
　By electrolysis using the electrolytic solution according to the present invention, it was subjected to quantitative analysis of inclusions or precipitation phase in the steel samples. As a control example was prepared comparative example electrolysis using the conventional electrolytic solution.
[0082]
　In the present embodiment, as the steel samples, steel containing 0.4 wt% Cu, after solution heat treatment of 1350 ° C. × 30min, with samples quenched in water.
　The electrolytic solution was prepared the following three types.
(1) 4% MS: 4 wt% methyl salicylate + 1% by mass salicylic acid + 1% by mass tetramethylammonium chloride which can be recovered conventionally known sulfide inclusions as residue (TMAC) that the Control Example.
(2) 4% MS + 5 % TETA: (1) a 4% MS, and triethylenetetramine (TETA) forming the Cu ions and complex 5% by volume have been added.
(3) 5% TETA: triethylenetetramine (TETA) 5 vol% (TETA) 5 vol% + 1 wt% electrolyte tetramethylammonium chloride (TMAC).
Incidentally, the solvent was methanol either (1) to (3).
[0083]
　For each of the electrolytic solution, samples were approximately 1g corresponding electrolyte, the content of Mn and Cu contained in the obtained electrolyte residue was quantified by wet chemical analysis, it was calculated content in the 1g steel sample.
[0084]
　The results are shown in Figure 4.
　In the figure, 3 bands graph of this are those indicated in% by superimposed been Mn and Cu detected from each electrolytic residue, from the left, (1) conventional electrolytic solution (4% MS) If electrolysis, (2) a conventional electrolytic solution, when the electrolyte in the electrolytic solution according to the present invention with the addition of TETA5 vol% (4% MS + 5% TETA), was added (3) TETA5 vol% (5% TETA) If electrolysis in an electrolytic solution according to the present invention, showing the. As the cathode and Pt electrodes both cases, was subjected to electrolysis.
[0085]
　Incidentally, the steel samples employed in Example by mirror polishing analyzed the distribution of component elements by EDS or the like, Cu contained in the sample have been mostly dissolves in the matrix portion of the sample, CuS Ya Cu 2 that does not exist in the sulfide form such as S is confirmed.
[0086]
　Nevertheless, Mn concentration in the electrolysis of a conventional electrolytic solution (4% MS) shown in (1) in FIG. 4, the electrolytic residue sulfides in steel sample are seen as the main component, is 143ppm Cu concentration of concentrations above (334 ppm) was measured.
[0087]
　The graph shown in (2) shows the concentration of the measured Mn and Cu from the electrolytic residue when the electrolyte in the electrolytic solution according to the present invention with the addition of 5 vol% triethylenetetramine (4% MS + 5% TETA).
　In this case, Cu component of the electrolytic residue is reduced to 62 ppm.
[0088]
　Further, (3) shows the measurement value in the case of triethylenetetramine 5 vol% electrolyte according to the present invention (5% TETA).
　Cu concentrations measured from the electrolytic residue was reduced to 12 ppm.
[0089]
　In the electrolytic solution according to the present invention of adding triethylenetetramine to the electrolytic solution, the conventional New Kuru pore filter for had dissolved, it is necessary to use insoluble filter the electrolyte.
　The present inventors have found that adopting the polyfluoroethylene made filter, and found that it is possible to prevent the dissolution phenomenon of the filter.
[0090]
　That is, by using the electrolyte solution according to the present invention, if the electrolyte steel samples improves the residue chemical analysis accuracy, it is possible to accurately identify and quantify the inclusions and precipitated phases present in the sample .
Industrial Applicability
[0091]
　By electrolyzing the steel sample using the electrolytic solution according to the present invention, it becomes possible to observe inclusions and precipitation phase in the sample in the form of leave originally present in the sample, and precipitated these inclusions also in chemical analysis phase, can eliminate contamination due to contamination by Cu or the like, it is possible to improve the accuracy of the chemical analysis.
DESCRIPTION OF SYMBOLS
[0092]
　4 metal samples
　5 inclusions and precipitation phase particle
　sixth electrode
　(cathode) 7 reference electrode
　8 power
　(potentiostat) 9 electrolytic solution
　10 electrolytic cell
　11 electrolyte residue

WE CLAIM

[Requested item 1]
　Etching the metal material in the electrolyte solution, a method of extracting the metal compound particles in the metal material,

a metal compound M ' x' A 'y the solubility product K sp [M' x ' A y' and,
the extraction target metal compound M included in the metal material x a y the solubility product K sp [M x a y When,
to form a complex containing a metal M 'which Δ is defined by the following equation becomes 10 or more the use of the electrolytic solution comprising a drug, and wherein the extraction method of the metal compound particles.

= PK delta sp [M ' x' A y ' ] -pK sp [M x A
y ] = (- log 10 K sp [M' x ' A y' ]) - (- log 10 K sp [M x A y ])
here, M and M 'are different metal elements, a is M or M' is a single atom or group to form a compound, x, x ', y, y' is M, M ' represents the composition ratio of the compound depends on the valence of a, said solubility product K sp is the value at 25 ° C. in an aqueous solution.
[Requested item 2]
　Method of extracting the metal compound particles according to claim 1, wherein the electrolyte is a non-aqueous solvent electrolyte.
[Requested item 3]
　The extraction target metal compound M x A y , wherein the is one or two of MnS or FeS, method of extracting the metal compound particles according to claim 1 or 2.
[Requested item 4]
　The pK sp is greater metal compound M ' x' A y ' metal M' is, for Hg, Ag, Cu, Pb, Cd, Co, characterized in that at least one of Zn, and Ni, claim method of extracting the metal compound particles according to any one of 1 to 3.
[Requested item 5]
　Wherein the agent is characterized in that it comprises a crown ether extraction method of the metal compound particles according to any one of claims 1-4.
[Requested item 6]
　Wherein the agent is polyethylene amines, ethylenediaminetetraacetic acid, characterized in that it comprises one kind or two or more kinds of cyclohexane diamine tetraacetic acid, according to any one of claims 1 to 5 method of extracting the metal compound particles.
[Requested item 7]
　Wherein the agent is characterized in that it comprises triethylenetetramine, method of extracting the metal compound particles according to claim 6.
[Requested item 8]
　Characterized in that said metallic material is a steel material, method of extracting the metal compound particles according to any one of claims 1 to 7.
[Requested item 9]
　Through an electrolytic solution after the etching the filter, when extracting metal compound particles as collected residue, any one of claims 1 to 8, wherein the filter is a tetrafluoroethylene resin filter method of extracting the metal compound particles according to (1).
[Requested item 10]
　Method for analyzing metal compound particles, characterized by analyzing the metal compound particles extracted by the extraction process of claim 1 any one the metal compound particles according to 9.
[Requested item 11]
　The metal material is etched, a electrolyte solution used to extract the metal compound particles in the metal material,

a metal compound M ' x' A 'y the solubility product K sp [M' x ' A y' and ' ,
extraction target metal compound M included in the metal material in x a y the solubility product K sp [M x a y When,
complexes containing a metal M 'which Δ is defined by the following equation becomes 10 or more formed to be comprised of the drug, and wherein the electrolytic solution.

= PK delta sp [M ' x' A y ' ] -pK sp [M x A
y ] = (- log 10 K sp [M' x ' A y' ]) - (- log 10 K sp [M x A y ])
here, M and M 'are different metal elements, a is M or M' is a single atom or group to form a compound, x, x ', y, y' is M, M ' represents the composition ratio of the compound depends on the valence of a, said solubility product K sp is the value at 25 ° C. in an aqueous solution
[Requested item 12]
　Electrolytic solution of claim 11 which is a non-aqueous solvent system.
[Requested item 13]
　The extraction target metal compound M x A y , wherein the is one or two of MnS or FeS, electrolyte solution according to claim 11 or 12.
[Requested item 14]
　The smaller solubility product K sp metal compound having an M ' x' A 'y is metal M', and Hg, Ag, Cu, Pb, Cd, Co, characterized in that at least one of Zn, and Ni the electrolytic solution according to any one of claims 11 to 13.
[Requested item 15]
　Wherein the agent is characterized in that it comprises a crown ether, the electrolytic solution according to any one of claims 11 to 14.
[Requested item 16]
　Wherein the agent is polyethylene amines, ethylenediaminetetraacetic acid, characterized in that it comprises one kind or two or more kinds of cyclohexane diamine tetraacetic acid, according to any one of claims 11-15 the electrolytic solution.
[Requested item 17]
　Wherein the agent is characterized in that it comprises triethylenetetramine, electrolyte solution according to claim 16.
[Requested item 18]
　Characterized in that said metallic material is a steel material, the electrolytic solution according to any one of claims 11 to 17.
[Requested item 19]
　The non-aqueous solvents are methanol, electrolyte solution according to any one of claims 11 to 18, characterized in that it comprises at least one ethanol.