第二相对析出强化铜合金大变形量多道次连续拉拔变形组织和性能的影响  

The influence of second phase on microstructure and properties of precipitation strengthening of copper alloy during multi-pass deep wire drawing

作　　者：王青[1] 梁淑华[1] 宋克兴[2,3] 国秀花[1,2,3] 周延军[2,3] 

机构地区：[1]西安理工大学陕西省电工材料与熔渗技术重点实验室,陕西西安710048 [2]河南科技大学材料科学与工程学院,河南洛阳471023 [3]有色金属共性技术河南省协同创新中心,河南洛阳471023

出　　处：《西安理工大学学报》2015年第3期301-305,共5页Journal of Xi'an University of Technology

基　　金：河南省杰出人才资助项目(134200510011);河南省高校科技创新团队资助项目(14IRTSTHN007);洛阳市科技攻关资助项目(1401055A);广东省教育部产学研结合资助项目(2012B091100038);陕西省电工材料与熔渗技术重点科技创新团队资助项目(2012KCT-25)

摘　　要：本文以典型析出强化型Cu-0.88Cr合金为研究对象,通过大变形量多道次连续拉拔变形试验,对比研究了Cu-0.88Cr合金和纯铜拉拔过程中的抗拉强度和延伸率变化规律,揭示了第二相对铜合金组织和性能的影响。结果表明:Cu-0.88Cr合金的抗拉强度随着变形量的增大呈现先升高后降低的趋势,当应变为0.7时,抗拉强度达到最大值475MPa。纯铜抗拉强度随变形量的增加先增大后基本保持不变。当应变为4.9时抗拉强度与纯铜接近。微观组织观察表明:未变形时,第二相与铜基体界面关系为共格界面。随着变形量的增大,第二相与基体的界面关系由共格界面向非共格界面发生转变,从而导致Cu-0.88Cr合金的抗拉强度在应变大于0.7时呈下降趋势。Cu-0.88Cr合金变形过程中延伸率低于纯铜,且在开始变形后随变形量增加变化不大,分析表明第二相存在降低了延伸率,但第二相与铜基体界面关系的转变对延伸率影响不明显。With this paper taking precipitation strengthening of Cu-0.88Cr alloy as the research object,andby comparing the changing laws of tensile strength,elongation of copper and Cu-0.88Cr during deep wire drawing,the influence of second phase on microstructure and properties of copper and Cu-0.88Cr is indicated.The results show that：the tensile strength of Cu-0.88Cr al-loy increases at first and then decreases as the true strain increases.When the true strain is 0.7, tensile strength reaches a maximum of 475 MPa.The tensile strength of copper increases at first and then remaines almost constant when the true strain increases.When the true strain is 4.9, the tensile strength of Cu-0.88Cr alloy is close to that of copper.Microstructure observations in-dicate that the interface relationship between second phase and matrix of Cu-0.88Cr alloy is co-herent before wire drawing,With an increase in the deformation,the interface relationship grad-ually changes from coherent relationship to incoherent relationship,leading to a decrease in ten-sile strength,whereby that the elongation of Cu-0.88Cr alloy is smaller than copper during draw-ing,and remaines almost constant when the true strain increases.Microstructure observations show that existence of second phase decreases the material plasticity,but the change of interface relationship between second phase and matrix Cu-0.88Cr alloy has no obvious effect on it.

关 键 词：Cu-0.88Cr合金 析出强化 界面 共格 应变 

分 类 号：TG146.11[一般工业技术—材料科学与工程]