Work Hardening and Tensile Behaviour of an Austenitic Stainless Steel at High Temperature

The work hardening and tensile behaviour of AISI 316L austenitic stainless steel deformed at temperatures between 600 and 1000 degrees C has been investigated. The alloy has been heat-treated according two different roots: the first solutioning treatment was imposed at 1100 degrees C and the second was designed at 875 degrees C to reduce the dynamic ageing that occurs at temperatures up to 650 degrees C in AISI 316L. In the solutionised material the work hardening data presented two linear regions: at high stresses the linearity has been described as the conventional Stage III of work hardening, whilst at low stresses the linearity has not been rationalised in any conventional stage of work hardening. In the second heat treatment alloy the work hardening data showed a single linear region at high stresses, whilst no linear stage occurred at low stresses. Therefore, the work hardening and tensile behaviour of AISI 316L has resulted to be significantly affected by the two different heat treatments and dynamic aging has been proved to influence work hardening behaviour well beyond the range of temperatures in which serrated yielding occurs.