Zr添加及冷轧形变对TiNi合金微观结构及力学性能的影响  

Effect of Zr addition and cold-rolling deformation on microstructure and mechanical properties of TiNi alloys

作　　者：张江 千佳祥 杨院霞 郝刚领[1] 王幸福 王新福 王伟国[1] 许巧平[1] ZHANG Jiang;QIAN Jiaxiang;YANG Yuanxia;HAO Gangling;WANG Xingfu;WANG Xinfu;WANG Weiguo;XU Qiaoping(College of Physics and Electronic Information,Yan’an University,Yan’an 716000,Shaanxi,China;Key Laboratory of Materials Physics,Institute of Solid State Physics,Chinese Academy of Sciences,Hefei 230031,China)

机构地区：[1]延安大学物理与电子信息学院,陕西延安716000 [2]中国科学院固体物理研究所材料物理重点实验室,合肥230031

出　　处：《材料工程》2024年第6期184-192,共9页Journal of Materials Engineering

基　　金：国家自然科学基金(52061038);陕西省“特支计划”区域发展人才专项(2020-44);陕西省青年科技新星资助项目(2013KJXX-11)。

摘　　要：采用真空电弧熔炼+吸铸制备Ti_(50-0.5x)Ni_(50-0.5x)Zr_(x)系列合金。金相观察和拉伸力学性能测试表明,添加微量的Zr可有效减小晶粒尺寸而呈现更高的抗拉强度和断后伸长率,过高的Zr含量易导致脆性金属间化合物Zr_(2)Ni的生成而降低力学性能。对Ti_(49.9)Ni_(49.9)Zr_(0.2)合金进行多道次冷轧形变和退火处理,结果表明:Ti_(49.9)Ni_(49.9)Zr_(0.2)合金的抗拉强度σb及断后伸长率δ均随冷轧退火道次的增加而提高,经过四道次的冷轧变形后,二者分别由未经轧制的561 MPa,11.14%提高到768 MPa,35.1%。SEM和TEM微观观察表明,冷轧过程中沿晶分布的硬质Ti_(2)Ni颗粒被剪切、破碎、细化,呈不连续分布。700℃退火处理后,形变组织发生回复再结晶,出现纳米晶和非晶区,且随冷轧形变的增加,基体中可见大量的板条状纳米孪晶组织和高密度位错。The Ti_(50-0.5x)Ni_(50-0.5x)Zr_(x)series alloys were prepared by vacuum arc melting and subsequent suction casting.Metallographic observation and tensile mechanical tests show that adding trace amount of Zr can reduce grain size and increase higher tensile strength and elongation,however,excessive Zr content can easily lead to the formation of brittle intermetallic compound Zr_(2)Ni and reduce its mechanical properties.The multi-pass cold-rolling deformation and annealing treatment on Ti_(49.9)Ni_(49.9)Zr_(0.2)alloy were carried out.The results show that the tensile strengthσb and the elongationδof the Ti_(50-0.5x)Ni_(50-0.5x)Zr_(x)alloys increase with the increase of cold-rolling deformation.Compared with the unrolled alloys,after four-passes coldrolling deformation,the tensile strength and the elongation after fracture of the alloys increase from 561 MPa,1.14%to 768 MPa,35.1%,respectively.Microscopic observation of SEM and TEM show that the hard Ti_(2)Ni particles distributed along the grain boundaries during the cold rolling process are sheared and broken,resulting in a discontinuous distribution of refinement.After 700℃annealing process,the deformed microstructure has recovery recrystallization,resulting in the appearance of nanocrystalline and amorphous regions.Moreover,a large number of plate-like nano-twin structures and high-density dislocations appear in the TiNi matrix with the increase of cold-rolling deformation.

关 键 词：TINI合金 力学性能 冷轧形变 微观结构 Zr元素添加 

分 类 号：TG146.2[一般工业技术—材料科学与工程]