Effect of welding on the stress corrosion cracking behaviour of prior cold worked AISI 316L stainless steel studied by using the slow strain rate test

Abstract

This work aims to assess the effect of welding on the stress corrosion cracking (SCC) behaviour of prior cold worked AISI 316L stainless steel from ultimate tensile strength (UTS) and time to failure (TF) obtained in slow strain rate tests (SSRTs), which are conducted in corrosive environment and in non-corrosive environment (air). The UTS of cold worked and welded specimens does not show significant variations with prior cold work (CW). However, the TF of cold worked and welded specimens depends on several phenomena that occur in the heat affected zone (HAZ), such as sensitization, recrystallization, recrystallized grain growth or thermal transformation of strain-induced martensite. Additionally, a metallographic study of SSRT tested specimens is performed with the aim of assessing the fracture mode, which proves to be ductile. This work shows that the combined effect of prior CW and welding does not give rise to SCC because the degree of sensitization (DOS) induced in the HAZ is not sufficient to direct the crack growth.