真空热压烧结Cu-Al_2O_3热变形行为研究  

Hot Compression Deformation Behavior and Established Constitutive Equations of Cu-Al_2O_3 Composites Prepared by Vacuum Hot-press Sintered

作　　者：张晓伟 孙静静 

机构地区：[1]机械工业第六设计研究院有限公司,河南郑州450007

出　　处：《有色金属材料与工程》2017年第3期139-143,共5页Nonferrous Metal Materials and Engineering

摘　　要：采用真空热压烧结法制备Cu-Al_2O_3复合材料,并在Gleeble-1500D热模拟机上对其进行高温压缩试验.阐述了内氧化原理,分析了真空热压烧结制备的铜基复合材料的微观组织和材料性能,研究了在变形温度为650~950℃,变形速率为0.01~5s^(-1),最大真应变为0.7时的流变应力行为.结果表明:变形温度和变形速率对流变应力的影响较大,随着变形温度的升高和应变速率的减小,峰值应力逐渐减小.采用双曲线正弦模型建立了材料高温变形时的流变应力本构方程,确定热变形激活能为220.7kJ/mol.Cu-Al2O3 composites were fabricated by vacuum hot-pressing sintering technique. Internal oxidation principle, microstructure and material properties of the composites were investigated. High temperature compression tests were carried out by using Gleeble-1500D thermal simulation apparatus. The flow stress behavior at deformation temperature of 650- 950 ℃ deformation rate of 0. 01-5 s1and maximum true strain of 0. 7 was studied. The results indicated that deformation temperature and strain rate had great influence on flow stress. With the increase of deformation temperature and the decrease of strain rate, the peak stress decreased. Using hyperbolic sine model, flow stress constitutive equation at high-temperature was established. The thermal activation energy was determined to be 220. 7 kj/mol.

关 键 词：CU-AL2O3复合材料 热压缩变形 流变应力 本构方程 

分 类 号：TB333[一般工业技术—材料科学与工程]