Cu-4.5%Ti合金的固态相变特征及性能  

Solid phase transformation characteristics and properties of Cu-4.5%Ti alloy

作　　者：程建奕[1] 何昆哲 邓明强 余方新[1] CHENG Jian-yi;HE Kun-zhe;DENG Ming-qiang;YU Fang-xin(School of Materials Science and Engineering,Nanchang University,Nanchang 330031,China)

机构地区：[1]南昌大学材料科学与工程学院,江西南昌330031

出　　处：《材料热处理学报》2020年第6期47-54,共8页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51661022,51161018);国家重点研发计划(2016YFB0301302)。

摘　　要：利用透射电镜(TEM)研究了Cu-4.5%Ti合金在固溶淬火、时效阶段的固态相变特征,采用维氏硬度计和FQR7501涡流导电仪测试了合金在400~500℃时效不同时间后的硬度和导电率。结果表明:合金在固溶淬火时就已发生了调幅分解和有序化,时效初期过渡态的1/4{11/20}有序化Cu3Ti相连续转变为具有D1a结构的β'-Cu4Ti有序相。经高温长时间的时效后,部分亚稳态的β'-Cu4Ti有序相最终转变为平衡态的β-Cu4Ti相。此亚稳、共格、有序的棒状β'-Cu4Ti相使合金获得了最大的硬度,而调幅组织和β'-Cu4Ti相在时效的早期对合金的强化贡献巨大。500℃时效2 h后,合金的硬度和电导率分别为290 HV0.3和9%IACS。The solid phase transformation characteristics of the Cu-4.5%Ti alloy during quenching and aging treatment were studied by transmission electron microscopy.The hardness and electrical conductivity of the alloy after aging at 400-500℃ for different time were measured by Vickers hardness test and FQR7501 vortex conductor.The results show that the alloy has undergone spinodal decomposition and ordering during quenching,and the 1/4{11/20}ordered Cu3Ti phase is continuously transformed into β'-Cu4Ti ordered phase with D1 a structure at the early stage of aging.After aging at high temperature for a long time,some metastable β'-Cu4Ti ordered phases eventually changes to equilibrium phase β-Cu4Ti.This metastable,coherent and ordered rod-like β'-Cu4Ti phase enables the alloy to obtain maximum hardness,while the spinodal decomposition microstructure and the β'-Cu4Ti phase contribute significantly to the strengthening of the alloy at the early stage of aging.The hardness and electrical conductivity of the alloy are 290 HV0.3 and 9%IACS after aging at 500℃ for 2 h.

关 键 词：Cu-Ti合金 调幅分解 有序化 性能 时效 

分 类 号：TG146.1[一般工业技术—材料科学与工程]