TiC粒径对颗粒增强铜基复合材料高温变形行为的影响  

Effect of TiC particle size of particle-strengthen Cu-based composites on deformation behavior at high temperature

作　　者：刘勇[1,2] 李辉[3] 杨志强[1] 田保红[1,2] 张毅[1,2] 

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023 [2]有色金属共性技术河南省协同创新中心,河南洛阳471023 [3]开封大学机械与汽车工程学院,河南开封475004

出　　处：《材料热处理学报》2015年第8期1-5,共5页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51101052);河南省高校重点科研项目(15A430006)

摘　　要：采用真空热压-内氧化烧结法成功制备Ti C粒径分别为3.2和25μm的30 vol%Ti C/Cu-Al2O3复合材料,对其进行了显微组织观察分析和性能测试;并利用Gleeble-1500D热力模拟试验机,研究了该复合材料在变形温度为450~850℃,应变速率为0.001~1 s-1条件下的热变形行为。结果表明：随着Ti C粒径的增大,复合材料的相对密度和导电率有所增加,而硬度略有下降。Ti C/Cu-Al2O3复合材料的真应力-真应变曲线主要以动态再结晶机制为特征,峰值应力随变形温度的降低或应变速率的升高而增加;高温变形条件下30 vol%Ti C/Cu-Al2O3复合材料流变应力本构方程可以用双曲线正弦方程和Z参数描述;热变形激活能随Ti C粒径增大而略有下降,其值分别为269.059 k J/mol（3.2μm）和234.288 k J/mol（25μm）。The 30 vol% TiC/Cu-A12O3 composites with TiC size of 3.2 μm and 25 p,m were prepared by hot-pressed sintering process in vacuum. The microstructure and properties of the composites were studied. The hot deformation behaviors of the composites were investigated by a Gleeble-1500D thermal simulator at 450-850 ℃ with strain rate of 0. 001-1 s-l. The results show that the relative densities values and the electrical conductivity of the composites increase with the increasing of size of TiC particles, while the hardness decreases a little. The features of the high-temperature flow stress-strain curves of the 30 vol% TiC/Cu-A12O3 composites indicate that the softening mechanism of the composites is the dynamic recrystallization. The peak stress increases with the decreasing deformation temperature or the increasing strain rate. The constitutive relation of the 30 vol% TiC/Cu-A12O3 composites under high-temperature conditions can be described by the hyperbolic-sine-type equation and Z parameter. The activation energy of the composites decreases a little with increasing of TiC particle size and the activation energy values are 269. 059 kJ/tool （3.2 μm） and 234. 288 kJ/mol （25 μm） , respectively.

关 键 词：颗粒增强铜基复合材料 TIC 粒径 激活能 本构方程 

分 类 号：TB333[一般工业技术—材料科学与工程] TG146.1[金属学及工艺—金属材料]