PRODUCTION OF AUSTENITIC STAINLESS STEEL EXHIBITING EXCELLENT INTEGRANULAR CORROSION RESISTANCE IN NITRIC ACID SOLUTION

摘要

PURPOSE:To improve the intergranular corrosion resistance of an austenitic stainless steel contg. P at a low ratio in a nitric acid soln. contg. oxidative ions by subjecting said steel to a solutionization heat treatment under specific temp. conditions. CONSTITUTION:The member made from the austenitic stainless steel such as SUS 304 contg. =0.04% P is subjected to the solutionization treatment by holding the same tor =2 minutes at =1000 deg.C and rapidly cooling the same at =40 deg.C/sec cooling rate down to 500 deg.C. The austenitic stainless steel member which has the excellent resistance to the intergranular corrosion even in the nitric acid soln. contg. ions such as hexad Cr ions having high oxidativeness and withstands long-term use as the structural stock in the environment of an apparatus for producing nitric acid, apparatus for retreatment of nuclear fuel, etc., where the member is exposed to the nitric acid soln.