| 【文章摘要】 Intercritical annealing(IA) at various temperatures followed by quenching and partitioning(IAQP) treatments was conducted on a cold-rolled Fe-0.2C-1.42Si-l.87Mn(wt%) sheet steel.Optimized microstructure and enhanced mechanical properties were achieved through appropriate adjustment of IA temperatures.The steel which was annealed at1,033 K for 600 s,then quenched to 573 K and partitioned at 693 K for 20 min,designated as 1033 QP steel,exhibits maximum 16.3 vol% retained austenite(RA) with good mechanical properties(ultimate tensile strength 886 MPa and total elongation 27%).It was found that the thermal and mechanical stabilities of RA are mainly influenced by the combined effect of its average carbon content and amount of adjacent martensite.Furthermore,the transformation-induced plasticity effect increased the peak n-values observed at the second stage of the work hardening of IAQP steels. |