Dissolution Behavior of Type 304, Type 316, and Type 430 Stainless Steels during Stress Corrosion Cracking

摘要

The dissolution behavior of type 304, type 316, and type 430 stainless steels during SCC was investigated in 0.82 kmol/m~3 chloride (pH 1.0) solutions by using ICP under constant applied stress or constant slow strain rate conditions. The maximum stress (#sigma#_m~(air)) of the specimens interrupted at various elongations under a constant applied stress was measured at room temperature with an Instron tensile machine. The dissolution behavior of the specimens under both conditions changed at t_(ss), the transition time in the corrosion elongation curve and at t_m, at which a stress becomes the maximum stress (#sigma#_m) obtained under a constant slow strain rate; that is, the dissolution rate was larger before than after t_(ss) and t_m. The v_m~(air) decreased with time to failure, but showed a rapid small change at t_(ss). The results are discussed in terms of the number of cracks, selective dissolution, active dissolution, and reduction in cross-sectional area.