Cu-3.27Ti合金热变形行为及组织演变过程  

Thermal Deformation Behavior and Microstructure Evolution of Cu−3.27Ti Alloy

作　　者：侯文忱 宋孟 HOU Wenchen;SONG Meng(School of Metallurgical Engineering,Anhui University of Technology,Maanshan 243032,China)

机构地区：[1]安徽工业大学冶金工程学院,安徽马鞍山243032

出　　处：《安徽工业大学学报（自然科学版）》2024年第5期466-473,共8页Journal of Anhui University of Technology（Natural Science）

基　　金：冶金减排与资源综合利用教育部重点实验室开放课题(JKF20-07);安徽省高校自然科学基金项目(KJ2019A0059)。

摘　　要：利用Gleeble-3500热模拟试验机,在变形温度为750~900℃、应变速率为0.1~10.0 s-1的条件下对铸态Cu-3.27Ti合金进行热压缩模拟试验;在此基础上构建Cu-3.27Ti合金高温本构关系模型、绘制热加工图,研究热变形温度、应变速度对Cu-3.27Ti合金热变形行为和组织演变过程的影响,优化其热变形工艺参数。结果表明:建立的高温本构关系模型可较好地表征Cu-3.27Ti合金变形温度、应变速率以及流变应力之间的关系,热加工图显示合金存在1个功率耗散峰值区和2个流变失稳区,功率耗散峰值约0.27,对应的变形条件为900℃,功率耗散峰值区与失稳区不重叠,理论上900℃条件下Cu-3.27Ti合金的热加工性能较好;变形温度和应变速率对Cu-3.27Ti合金微观组织动态再结晶比例和再结晶晶粒平均直径均有明显影响,两者均随变形温度和应变速率的升高而上升,当组织完全再结晶后变形温度和应变速率对晶粒平均直径的影响更显著;Cu-3.27Ti合金在750℃变形时细小的再结晶晶粒呈链状分布于初始晶粒周围,呈现出流变失稳特征,变形条件为900℃/10.0 s^(-1)时,合金的微观组织完全再结晶且晶粒比较细小均匀,比较适于进行热加工。The hot compression simulation test of Cu-3.27Ti alloy as cast was carried out at deformation temperature-1 of 750-900℃and strain rate of 0.1-10.0 s with Gleeble-3500 thermal simulation testing machine.On this basis,the high temperature constitutive relation model of Cu-3.27Ti alloy was established,and its hot working diagram was drawn.The effects of thermal deformation temperature and strain rate on the thermal deformation behavior and microstructure evolution of Cu-3.27Ti alloy were studied,and the technological parameters of thermal deformation were optimized.The results show that the established high temperature constitutive relation model can well characterize the relationship between deformation temperature,strain rate and flow stress of Cu-3.27Ti alloy.The hot working diagram shows that there is one peak power dissipation region and two rheological instability regions in Cu-3.27Ti alloy,and the peak power dissipation is about 0.27,the corresponding deformation condition is 900℃,and the peak power dissipation region does not overlap with the instability region.Theoretically,Cu-3.27Ti alloy has better thermal workability at 900℃.Deformation temperature and strain rate have obvious effects on the dynamic recrystallization ratio and average diameter of recrystallization grains of Cu-3.27Ti alloy microstructure,both of which increase with the increase of deformation temperature and strain rate.When the microstructure is completely recrystallized,the influence of deformation temperature and strain rate on the average diameter of grain is more significant.When Cu-3.27Ti alloy is deformed at 750℃,the fine recrystallized grains are distributed around the initial grains in chain structure,exhibiting rheological instability characteristics.When the deformation condition is 900℃/10.0 s^(-1),the microstructure of the alloy has been completely recrystallized and the grains are relatively small and uniform,which is suitable for hot processing.

关 键 词：热变形 本构关系模型 热加工图 动态再结晶 CU合金 组织演变 

分 类 号：TG146.1[一般工业技术—材料科学与工程]