Local Corrosion of Austenitic Steels and Alloys

Abstract

The principles of doping of austenitic unstabilized Cr-Ni and Cr-Mn-Ni steels resistant against pitting, slit, and intergranular corrosion (IGC) in weakly and strongly oxidative media are considered. The features of the effect of individual and joint doping with nitrogen, molybdenum, and silicon steels on their resistance to local corrosion have been studied. The ambiguous effect of joint doping with nitrogen and molybdenum of Cr-Mn-Ni steels on their resistance against pitting corrosion is revealed. It has been established that the presence of silicon, in addition to nitrogen and molybdenum, is a prerequisite for eliminating the propensity to the IGC after a long release of chromium-nickel steels. The introduction of silicon into Cr-Ni steel with 0.03% C, with a balanced content of Cr, N, Mo, and Si, equates it with a particularly low-carbon steel containing 0.003% C. Based on the above doping principles, a number of austenitic steels are designed for production equipment that is resistant to local corrosion in chloride-containing media and nitric acid.