Temperature-dependence of multiaxial non-proportional cyclic hardening of type 316 stainless steel

The temperature dependence of the multiaxial cyclic behaviour of type 316 stainless steel was elucidated experimentally. Cyclic tests under constant total-strain amplitudes were performed for uniaxial tension-compression and circular strain paths at several temperatures ; room temperature, 200 deg C, 400 deg C, 500 deg C, 600 deg C and 700 deg C. The strain amplitudes of the cycles were specified to be 0.2, 0.3 and 0.4 % under a constant strain rate of 0.2 %/min. It was observed that though strain hardening for circular cycles was larger than that of the tension-compression cycles at every temperature, the effect of nonproportionality in cyclic hardening decreased with the increase in temperature. The cyclic hardening was significant, particularly in the temperature range between 400 deg C and 500 deg C. (author)