CORROSIVE LIQUID FOR EMERGENCE OF PRIMARY AUSTENITE GRAIN BOUNDARY OF STEEL MATERIAL AND METHOD FOR MAKING PRIMARY AUSTENITE GRAIN BOUNDARY OF STEEL MATERIAL EMERGE

摘要

PPROBLEM TO BE SOLVED: To provide a corrosive liquid enabling emergence of primary austenite grain boundary in overall steel materials including a steel material with an ultra-fine grain texture of grain size of 2m or less. PSOLUTION: This corrosive liquid is composed an aqueous solution containing a picric acid, a surfactant, a chloride and an oxalic acid. The aqueous solution contains one or two selected from hydrochloric acid, glycerin, and alcohols as a reaction rate regulating agent. A section of a steel material is mirror-finished, and immersed in the above corrosive liquid to make the primary austenite grain boundary of the steel material selectively emerge. PCOPYRIGHT: (C)2005,JPO&NCIPI