Electrolytic corrosion method for grain morphology display of IN718 nickel-based superalloy

The invention belongs to the technical field of metallographic electrolytic polishing corrosion, and particularly relates to an electrolytic corrosion method for displaying the grain morphology of an IN718 nickel-based high-temperature alloy, in particular to an electrolytic corrosion method for displaying the grain morphology of the IN718 nickel-based high-temperature alloy. The invention aims to solve the problems that a traditional chemical corrosion process cannot accurately display the grain boundary, and a corrosive agent is short in effective use time and low in success rate. The method comprises the following steps: 1, cutting an IN718 nickel-based high-temperature alloy sample, and carrying out mechanical grinding and polishing and cleaning to obtain a bright and clean metallographic sample; 2, preparing an oxalic acid electrolytic solution; 3, the metallographic sample is put into an oxalic acid electrolytic solution for electrolytic corrosion, and an electrolytic corrosion sample is obtained; fourt