Hot Working of High Nitrogen Austenitic Stainless Steel

With hot rolling in laboratory and Gleeble thermal simulator,the hot working of a high nitrogen austenitic stainless steel(HNASS)was researched.The results showed that dynamic recovery(DRV)and dynamic recrystallization(DRX)in HNASS occurred during hot working,and both of them had well-defined stress peaks in flow curves under different conditions.During hot rolling experiment at temperature from 950 to 1050 ℃,recrystallization phenomenon does not take place in test material until the deformation ratio is up to 40%.Recrystallization influences remarkably the strength and ductility of material,and the test HNASS possesses better combination of strength with ductility.According to the curve of θ-σ(strain hardening rate-steady state stress),the DRX critical strain of test material was determined.Also,the activation energy of hot working was calculated to be 746.5 kJ/mol and the equation of hot working was obtained.