Experimental investigation of austenitic stainless steel material at elevated temperatures

Based on S30408 austenitic stainless steel, the mechanical properties of materials in flat and corner regions were investigated by steady state tests and transient state tests at elevated temperatures. The stress-strain curves of stainless steel at elevated temperatures obtained by the two test methods were compared and analysed. The results show that the mechanical properties of stainless steel obtained by the two test methods are approximately equivalent when the temperatures are lower than 700 °C; otherwise, the mechanical properties obtained by the two test methods are not completely equivalent. The formulae of the reduction coefficient of mechanical properties of stainless steel at elevated temperatures were put forward. The influences of strain hardening indices nθ and mθ on the stress-strain curves of stainless steel at elevated temperatures were simulated. The results show that there are large deviations in the strain hardening indices obtained by different tests.