Investigation on the Mechanical Properties at Room Temperature of Q and P Steel Sheet With Ultrahigh Strength

摘要

Quenching and Partitioning (Q&P) steel is a new type ultrahigh strength steel with transformation induced plasticity (TRIP) effect. Uniaxial tensile experiments of the Q&P steel at room temperature were carried out to investigate the effects of sampling angle and strain rate on its mechanical properties. Experimental results show that the flow stress-strain curve, the hardening component n, the anisotropy coefficient through thickness r and the elongation of the Q&P steel are not sensitive to the sampling angle. However, the hardening component n and the elongation of the Q&P steel decrease with increasing the strain rate. Due to the Q&P steel with TRIP effect, when the strain rate greater, the deformation work will transform to the internal energy of specimen, and the TRIP effect of the Q&P steel will be inhibited, which results in less transformed retained austenite. X ray diffraction experiments were performed to verify it.