低碳锰(铌)钢控轧控冷实验研究

通过TMCP研究了低碳锰钢和添加微量Nb的低碳锰铌钢的组织和力学性能的影响因素.研究了Nb对实验钢显微组织和力学性能的影响.Nb的添加能够细化铁素体晶粒,促进铁素体转变,对贝氏体形成有一定的抑制作用.相对低碳锰钢来说,铌的加入减少了贝氏体的体积分数,贝氏体强化效果减弱,钢的屈强比升高.通过增加冷速和降低卷取温度,可以使低碳锰铌钢获得一定量的贝氏体,综合性能较佳.低碳锰铌钢的主要强化机制有细晶强化、贝氏体相变强化和析出强化.

Study on a low carbon manganese (niobium) steel by controlled rolling and controlled cooling process

Thermo-mechanical controlled process(TMCP) experiments have been carried out on low carbon manganese(niobium) steels.Effects of niobium on microstructures and mechanical properties of the steels have been studied.The addition of niobium can refine the ferrite grains and accelerate ferrite transformation,thus retarded the formation of bainite.The existence of niobium decreased the volume fraction of bainite and yield ratio of the experimental steel became higher.A certain amount of bainite in low carbon manganese-niobium steel can be gained by controlling technological parameters,especially accelerated cooling and decreased coiling temperature.It is also concluded that the strengthening mechanisms included fine ferrite grain hardening,bainite transformation hardening and precipitation hardening.