Elevated temperature mechanical properties of shock-strengthened austenitic stainless steel

The mechanical properties of explosively shock-strenghened (320 kbar) Type 304 stain-less steel were investigated. Tensile tests were performed on the shock-strengthened material at temperatures ranging from room temperature to 650°C. The shock hardening caused large increases in yield strength, moderate increases in ultimate strength, and reductions in ductility. Annealing studies on the shock-strengthened stainless steel indicated that considerable amount of the shock-induced strength stainless steel indicated that considerable amount of the shock-induced strength increase is retained after long time anneals at 700 and 750°C. However, metallographic studies on the annealed material indicated the presence of fine carbide particles which may partly account for the strength of the material. Creep studies indicated that the minimum creep rate at 650°C was reduced by a factor of 1000 due to shock strengthening.