退火工艺对强塑性变形珠光体钢丝组织和性能的影响

Effect of annealing process on microstructure and mechanical properties of severe plastic deformation pearlitic steel wire

用TEM、XRD研究了强塑性变形(ε=2.60)SWRH72A钢丝经不同温度(100-400℃)退火处理后的微观结构变化。XRD分析显示强塑性变形引起SWRH72A钢丝中渗碳体回溶,部分碳原子溶入铁素体形成过饱和铁素体,过饱和铁素体中含碳量约0.34at%。由TEM分析可知强塑性变形钢丝经200-300℃退火,由于渗碳体颗粒的弥散析出,钢丝强度升高到2400MPa。退火温度进一步升高到400℃,渗碳体片开始球化,钢丝强度大幅降低,但塑性显著增加。

Effect of annealing process on microstructure of SWRH72A steel wire under severe plastic deformation were investigated by TEM and XRD.The XRD analysis shows that severe plastic deformation causes partial of cementite decomposition and dissolution of carbon into ferrite up to 0.34 at %.Cementites form which distribute dispersively in matrix when the annealing temperature reachs 200-300℃,resulting in increasing the strength of wire.Annealing temperature reachs 400℃,the strength of wire decreases sharply,but the plasticity enhances significantly.