The effect of precipitated phases on the creep in 300s type austenitic stainless steel used in auto-tailpipe was studied. Flat tensile samples with marker scratches on the surface were strained at slow rate at 400°C. It show that the sensitized material decreased creep rate and needed more stress to generate deformation of grain boundary, suggesting Cr carbides decreased the grain boundary sliding. Thus, the resistance to SCC crack propagation could be improved. Characterizations of the tensile samples were carried out using a SEM in order to understand whether second phases can affect the creep behavior and grain boundary moving.
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