The investigation of ultra-high strength steel by quenching-partitioning-tempering (Q-PT) process

摘要

By comparing quenching and partitioning(Q&P) process proposed by Speer et al with quenching-partitioning-tempering (Q-P-T) process proposed by Hsu, an Fe-Mn-Si-Ni-Nb ultra-high strength steel with the carbon content less than 0.5 wt% suffered from the Q-P-T process was designed and the microstructure was characterized. The results indicate that this Q-P-T steel exhibits the tensile strength over 2000 MPa combined with good elongation above 10%. Experimental results indicate that the Q-P-T steels have become a new family of ultra-high strength ones. By comparison of the properties of various phases in structural steels, the design principle of microstructures for ultra-high strength steel with adequate ductility is further proposed.