METHOD FOR EXTRACTING METAL COMPOUND PARTICLES, METHOD FOR ANALYZING METAL COMPOUND PARTICLES, AND THE USE OF THE ELECTROLYTE SOLUTION FOR EXTRACTING METAL COMPOUND PARTICLES PRESENT IN A METAL MATERIAL

The object of the present invention is such that a surface exchange of metal fine particles by Cu ions, or the like is inhibited in order to prevent formation of Artificial CuS or the like, in extraction and analysis of the metal fine particles (inclusions and precipitates) in a metal material by electrolytic corrosion in a solvent-based electrolytic solution, without significantly changing conventional extraction and analysis methods. A method for extracting metal compound particles in a metal material by etching the metal material in an electrolytic solution, characterized by using the following electrolytic solution, wherein it comprises a chemical agent that forms a complex containing metal M' wherein ” defined by the following formula is 10 or more, ” = pKsp M €² x €² Ay €² ˆ’ pKsp MxAy = ˆ’ log 10 Ksp M €² x €² Ay €² ˆ’ ˆ’ log 10 Ksp MxAy wherein a solubility product of metal compound M'x'Ay' is defined as Ksp[M'x'Ay'], and a solubility product of metal compound to be extracted MxAy, which is contained in the metal material, is defined as Ksp[MxAy], as well as the electrolytic solution therefor.