Mo含量对粉末冶金Ti-Mo合金组织与力学性能的影响  

Effects of Mo content on microstructure and mechanical properties of Ti-Mo alloys prepared by powder metallurgy

作　　者：王楚凡 蔡奇 刘金旭[1,2] 严细锋 WANG Chu-fan;CAI Qi;LIU Jin-xu;YAN Xi-feng(Beijing Institute of Technology,School of Materials Science and Engineering,Beijing 100081,China;Beijing Institute of Technology,China National Key Laboratory of Science and Technology on Materials under Shock and Impact,Beijing 100081,China)

机构地区：[1]北京理工大学材料学院,北京100081 [2]北京理工大学冲击环境材料技术国家重点实验室,北京100081

出　　处：《中国有色金属学报》2023年第2期328-342,共15页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(52171027);北京理工大学青年教师学术启动计划(202008002)。

摘　　要：采用冷等静压后常压烧结的方法制备了6种不同Mo含量(质量分数)的Ti-Mo合金,探究了Mo含量对合金组织与力学性能的影响规律与机理。结果表明:采用粉末冶金方法可以制备出成分均匀且相对密度高达99.26%的Ti-Mo合金;随着Mo含量的增加,粉末冶金Ti-Mo合金相对密度逐渐降低,β相比例逐渐增加,当Mo含量达到30%时,合金为纯β相。Ti-Mo合金中针状α相、板条α相、晶界α相随Mo含量增加依次消失,等轴β晶粒尺寸逐渐减小。Ti-Mo合金的准静态压缩屈服强度与显微硬度均随Mo含量的增加呈先上升后下降的变化趋势,临界断裂应变的变化趋势则相反,高Mo含量的合金展现出优异的压缩塑性变形能力。针状α相是影响合金强塑性的最重要组织特征,随着针状α相体积分数的增高,合金强度提高、塑性下降。此外,具有低硬度和体心立方结构的β相比例越高,合金塑性越高,但强度下降。Six kinds of Ti-Mo alloys with different Mo contents(mass fractions)were prepared by cold isostatic pressing followed by atmospheric pressure sintering.The effects of Mo content on microstructure and mechanical properties of the alloy were investigated,as well as the related mechanism.The results show that Ti-Mo alloys with uniform composition and relative density up to 99.26%can be prepared by powder metallurgy.With the increase of the Mo content,the relative density of powder metallurgical Ti-Mo alloys decreases gradually,and the volume fraction ofβphase increases gradually.When the Mo content reaches 30%,the alloy is pureβphase.The acicularαphase,lamellarαphase,and grain boundaryαphase disappear successively with the increase of Mo content.The quasi-static compressive yield strength and microhardness of the Ti-Mo alloys increase first and then decrease with the increase of Mo content,while the variation tendency of the critical fracture strain is on the contrary.The alloys with high Mo content exhibit excellent compressive plasticity.The acicularαphase is the most important factor in affecting the strength and plasticity of alloys.With the increase of the volume fraction of acicularαphase,the strength increases but the plasticity decreases.In addition,the higher the content ofβphase with low hardness and body-centered cubic structure,the higher the plasticity of Ti-Mo alloys,but the strength decreases.

关 键 词：粉末冶金 TI-MO合金 微观组织 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]