Thermal aging effect on fracture toughness of GTAW/SMAW of 316L stainless steel: experiments and applicability of existing CASS models

This paper presents thermal aging effect on fracture toughness properties of GTAW (gas tungsten arc welding) and SMAW (shielded metal arc welding) of 316L stainless steels, and investigates the applicability of the existing three thermal aging models for CASS (cast stainless steels). Thermal aging was carried out at 350 °C for up to 15,000h and at 400 °C up to 8,000h. After aging, tensile and fracture toughness tests using 0.5T C(T) specimens were carried out at room temperature and at 288 °C. Comparing with the predictions using three (ANL, French and H3T) thermal aging models for CASS show that the predictions can be very non-conservative at operating temperature, and thus that the existing thermal aging models for CASS cannot be applied to the welded stainless steels.