Creep of 316 stainless steel at 550 and 600°C and the effects of short duration overloads on creep at 550°C

Abstract

This paper contains the results of a series of uniaxial creep and plasticity-creep interaction tests performed on 316 stainless steel specimens at 550 and 600°C. Tests with durations of up to 49 000 h were performed. At 550°C, renewed primary and secondary creep was obtained at stresses of about 320 MPa and below. Above 320 MPa at 550°C and at all stresses at 600°C, the usual type of creep behaviour was observed. The effects of intermittent overload stresses (every 168 h) which caused plastic strains to occur were investigated at 550°C. The failure times were generally unaffected but the creep strains were reduced. However, due to the increments of plastic strain obtained during the overloads, the total strains at failure were increased.