时效温度对Ti-5Al-4Zr-10Mo-3Cr钛合金微观组织及力学性能的影响  

Effect of aging temperature on microstructure and mechanical properties of Ti-5Al-4Zr-10Mo-3Cr titanium alloy

作　　者：谭皎 张伯岩 朱文光 孙巧艳[1] Tan Jiao;Zhang Boyan;Zhu Wenguang;Sun Qiaoyan(State Key Laboratory for Mechanical Behavior of Materials,Xi'an Jiaotong University,Xi'an Shaanxi 710049,China)

机构地区：[1]西安交通大学金属材料强度国家重点实验室,陕西西安710049

出　　处：《金属热处理》2022年第1期217-225,共9页Heat Treatment of Metals

基　　金：国家自然科学基金项目(51671158);国家重点基础研究发展计划(973计划)(2014CB644003)。

摘　　要：研究了Ti-5Al-4Zr-10Mo-3Cr合金经过β相区固溶(880℃)、不同温度时效(540~620℃)处理后次生α相(α;)析出形貌及其对力学性能的影响。结果表明:随着时效温度由540℃升高至620℃,合金中析出α;相片层厚度由0.030μm增加到0.142μm,屈服强度由1353 MPa降低至1074 MPa,断后伸长率由2.5%升高至11.4%,即时效析出的微米级片层α;能够显著调控合金的力学性能。此外,时效温度升高使合金的拉伸断裂由沿晶脆性断裂为主转变为韧窝穿晶为主的韧性断裂方式。Ti-5Al-4Zr-10Mo-3Cr合金时效析出的片层状α;相的厚度大于0.1μm,合金的断后伸长率≥6%。当时效温度为600℃时,合金的硬度为387 HV10,抗拉强度为1182 MPa,伸长率为8.5%,具有良好的强塑性匹配。Precipitation behavior and mechanical properties of secondary α phase(α;) in the Ti-5 Al-4 Zr-10 Mo-3 Cr alloy after solution treatment in β phase region(at 880 ℃) and aging at different temperatures(540-620 ℃) were studied. The results show that with the aging temperature increasing from 540 ℃ to 620 ℃, the thickness of precipitated α;increases from 0.030 μm to 0.142 μm, the yield strength decreases from 1353 MPa to 1074 MPa, and the elongation after fracture increases from 2.5% to 11.4%. This indicates that the micro-scaled α;precipitated by aging can regulate the mechanical properties of the alloy. In addition, with the increase of aging temperature, the tensile fracture of the alloy changes from intergranular brittle fracture to dimple transgranular ductile fracture. The thickness of the α precipitation in the Ti-5 Al-4 Zr-10 Mo-3 Cr alloy is greater than 0.1 μm, which brings about the elongation after fracture larger than 6%. When the aging temperature is 600 ℃, the hardness, tensile strength and elongation after fracture are 387 HV10, 1182 MPa and 8.5% respectively, possessing good combination of strength and ductility.

关 键 词：Β钛合金 时效处理 微观组织 力学性能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]