Compressive Deformation Behavior of Thick Micro-Alloyed HSLA Steel Plates at Elevated Temperatures

Abstract

The hot deformation behavior of a heavy micro-alloyed high-strength low-alloy (HSLA) steel plate was studied by performing compression tests at elevated temperatures. The hot compression tests were carried out at temperatures from 923 K to 1,223 K with strain rates of 0.002 s −1 and 1.0 s. A long plateau region appeared for the 0.002 s -1 strain rate, and this was found to be an effect of the balancing between softening and hardening during deformation. For the 1.0 s -1 strain rate, the flow stress gradually increased after the yield point. The temperature and the strain rate-dependent parameters, such as the strain hardening coefficient (n), strength constant (K), and activation energy (Q), obtained from the flow stress curves were applied to the power law of plastic