添加微米级ZrC颗粒的低碳微合金钢强韧性研究

Study on strengthening and toughening of low-carbon microalloyed steel added with micron-grade ZrC particles

真空条件下,在低碳微合金钢中添加体积分数为1.1%的微米级ZrC陶瓷颗粒,在450 mm热轧试验机上进行轧制,将ZrC颗粒作为形变核心和奥氏体及形变诱导铁素体的再结晶核心。热轧后晶粒被细化到5.5μm,钢板抗拉强度和屈服强度分别达到635 MPa和517.5 MPa,钢板强韧化的机制是综合引入了形变强化、相变强化、第二相粒子强化及细晶强化的结果。热轧钢板的显微组织为铁素体加少量珠光体,钢中存在大量第二相粒子,并呈弥散分布。

In vacuum conditions, micron-grade ZrC ceramic particles with 1.1 % volume fraction used as the deformation center and recrystallization center of austenite and deformation-induced ferrite were added into a low-carbon mieroalloyed steel. The steel was hot-rolled in 4450 mm experimental hot mill. After hot rolling, the steel grains were refined to 5.5um, the tensile strength and yield strength of the hot rolled steel were 635 MPa and 517. 5 MPa respectively. The mechanism of strengthening and toughening of the steel is a comprehensive result of deformation strengthening, phase transformation strengthening, second-phase strengthening and fine-grain strengthening. The microstructure of the hot rolled steel is ferrite with a tiny amount of pearlite. A large number of second-phase particles was dispersed in the steel.