Stress corrosion cracking of LDX 2101® duplex stainless steel in chloride solutions in the presence of thiosulphate

Stress corrosion cracking behaviour of a LDX 2101® stainless steel was studied through SSRT in a 20% NaCl solution at 80°C and in the standard NACE TM-0177 solution at 25°C in the presence of thiosulphate. The LDX 2101® resulted susceptible to SCC in the presence of small thiosulphate concentrations. Tests were performed in the NACE solution at various pH and temperatures. When thiosulphate concentration was increased to 10-1M in the 20% NaCl at 80°C or NACE solution (pH 2.7 and 10-2M S2O32-) temperature was rise to 80°C the selective corrosion of the ferrite phase became predominant on SCC.