对冷拔钢丝进行不同保温时间下的等温处理,研究此过程中钢丝组织、力学性能的变化。等温初期,铁素体片中析出细小渗碳体颗粒,钢丝的抗拉强度有所上升,塑性急剧下降,并出现扭转分层现象。等温后期,渗碳体片发生球化,析出相长大,并且铁素体片发生明显回复,三者综合作用造成钢丝的抗拉强度下降,塑性提高。 Cold-drawn steel wire was subjected to isothermal treatment under different holding time to study the changes of the steel wire structure and mechanical properties in this process. In the initial phase of isothermal temperature, fine cementite particles were precipitated in the ferrite sheet, the tensile strength of the steel wire increased, the plasticity dropped sharply, and stratification was reversed. In the late isothermal phase, the cementite was spheroidized, precipitated and phase grew up, and the ferrite sheet obviously recovered. The combined effect of the three resulted in the decrease of tensile strength and plasticity of the steel wire.