大应变冷拔钢丝的强化模型  

Strengthening model of steel wire under heavy cold-drawing deformation

作　　者：涂益友[1] 周兴海[1] 刘伟[1] 蒋建清[1] 

机构地区：[1]东南大学江苏省先进金属材料高技术研究重点实验室,江苏南京211189

出　　处：《材料热处理学报》2009年第1期28-31,44,共5页Transactions of Materials and Heat Treatment

基　　金：国家"973"前期研究专项(2007CB616900);国家科技支撑计划(2007BAE15B05);新世纪优秀人才支持计划(SCET-04-11471)

摘　　要：采用扫描电镜观察了不同应变量拉拔变形后SWRH72A钢丝的显微组织,并统计了珠光体片层间距的变化。通过透射电镜分析了变形后铁素体中的位错分布状态,测量了不同应变量拉拔变形后钢丝的力学性能,并基于钢丝微观组织结构建立了钢丝的强化模型。结果表明,随着拉拔应变量的增大,珠光体片层间距逐渐减小,钢丝强度随之升高。综合分析珠光体片层间距和钢丝强度的变化规律得出,应变量较小时,珠光体片层间距较大(>100nm),钢丝加工硬化符合Hall-Patch定律;应变量较大时,珠光体片层间距较小(<100nm),钢丝加工硬化符合奥罗万(Orowan)机制。The mierostructnre of SWRH72A steel wire under cold-drawn deformation was studied by means of SEM and TEM. The change of the pearlite interlamellar spacing with increasing drawing strain was quantitatively analysed. The mechanical property of steel wire was measured, and work hardening model was established based on experiments. The results indicate that the interlamellar spacing of pearlite decreases progressively during the cold drawing process. Tensile strength of the steel wire increases with increasing drawing strain. In the initial stages of drawing, the strengthening of peatlite steel is accorded with Hall-Petch relationship. There is a deviation from the Hall-Perch relationship when the interlamellar spacing of pearlite decreases to less than 100nm, but Orowan hardening mechanism operates.

关 键 词：冷拔钢丝 微观组织 屈服 强化机制 

分 类 号：TG115.5[金属学及工艺—物理冶金]