热处理对添加少量Cr、Fe的Ti-Ni合金组织和力学性能的影响  

Effect of heat treatment on microstructure and mechanical property of Ti-Ni-X(Cr,Fe)alloys

作　　者：欧阳盛[1] 罗兵辉[1] 李彬[1] 高阳[1] 曾丽舟[1] 范文丽[1] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《粉末冶金材料科学与工程》2017年第2期169-176,共8页Materials Science and Engineering of Powder Metallurgy

基　　金：总装备部预研项目(LH201236)

摘　　要：采用真空熔炼法制备Ti_(45)Ni_(55)Cr_(0.3)和Ti_(45)Ni_(52)Fe_3合金(元素含量为摩尔分数)铸锭,对其进行均匀化处理以及850℃/1 h固溶和水淬后,分别采用3种不同的工艺进行热处理:1)850℃/1 h固溶,2)375℃/1 h时效,3)25%冷轧+375℃/1 h退火,研究热处理工艺对合金的相变特性、力学性能、内耗性能和微观组织的影响。结果表明,Ti_(45)Ni_(55)Cr_(0.3)和Ti_(45)Ni_(52)Fe_3合金的基体均由B2与R相组成;Ti_(45)Ni_(55)Cr_(0.3)合金经过375℃/1 h时效或25%冷轧+375℃/1 h退火处理后,析出Cr3Ni2粒子,时效后抗拉强度为1 385 MPa,时效升温过程的峰值内耗达到0.53;Ti_(45)Ni_(52)Fe_3合金经过25%冷轧+375℃/1 h退火后析出Ti3Ni4相,抗拉强度为770 MPa;与其它热处理工艺的升温过程相比,Ti_(45)Ni_(52)Fe_3合金的时效升温过程峰值内耗最高,达到0.158;降温过程中,Ti_(45)Ni_(55)Cr_(0.3)合金在时效降温过程中发生B2→R→M相变,退火的降温过程中发生B2?R相变,而Ti_(45)Ni_(52)Fe_3合金在退火的降温过程中发生B2→R→M相变。Ti45Ni55Cr0.3 and Ti45Ni52Fe3 （at.%） alloy ingots were prepared by smelting technique, and then three sets of heat treatments were carried out as follows： 850 ℃/1 h solution, 375 ℃/1 h aging and 25% coke rolling＋375 ℃/1 h annealing. The effects of heat treatments on phase transformation behaviors, mechanical properties, damping characteristics and microstructure of Ti-Ni-X（Cr,Fe） alloys were investigated. The results show that the matrix of both Ti45Ni55Cr0.3 and Ti45NiszFe3 alloys is a mixture of B2 and R phases at room temperature; After 375 ℃/1 h aging or 25% reduction＋375 ℃/I h annealing, Ti45NissCr0.3 has a matrix dotted with Cr3Niz precipitates, and the tensile strength of aged alloy is 1 385 MPa and tan6 to 0.53; The 25% cold-rolled＋375 ℃/1 h annealed Ti45Nis2Fe3 alloy has a matrix dotted with Ti3Ni4 precipitates, and the tensile stength is 770 MPa; Compared with other heat treatment process, the aged Ti45Ni52Fe3 has the maximum tan8 value of 0.158; B2---,R---,M transformations take place during cooling process of aging in the Ti45Ni55Cr0.3 alloy, B2--R transformation takes place during cooling process of cold rolling＋annealing in Ti45Ni55Cr0.3 alloy, B2---R---,M transformations take place during cooling process of cold rolling＋annealing in Ti45Ni52Fe3 alloy.

关 键 词：Ti45Ni55Cr0.3合金 Ti45Ni52Fe3合金 力学性能 马氏体相变 内耗 

分 类 号：TG166.5[金属学及工艺—热处理]