激光立体成形TA15-xTi2AlNb均质材料的组织与性能研究  

Microstructure and Mechanical Property of Laser Solid Formed TA15-xTiAlNb Alloys

作　　者：周庆军 漆仲亮 严振宇 陈静[2] 黄卫东[2] Zhou Qingjun;Qi Zhongliang;Yan Zhenyu;Chen Jing;Huang Weidong(Captial Aerospace Machinery Corporation Limited,Beijing 100076,China;State Key Laboratory of Solidi fication Processing,Northwestern PolytechnicaI University,Shaanxi 710072,China)

机构地区：[1]首都航天机械有限公司,北京100076 [2]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《应用激光》2020年第3期421-429,共9页Applied Laser

基　　金：航天科技创新基金资助项目(项目编号:X工艺20160095-007);航天科技联合基金资助项目(项目编号:6141B06310201)。

摘　　要：文章利用激光立体成形技术,制备了六组不同质量分数配比TA15-xTi2AlNb(x=0%、20%、40%、60%、80%、100%)均质材料块状试样,并研究了随着合金中Ti2AlNb含量的增加,各组均质材料显微组织及力学性能的变化。研究结果表明,晶粒形态方面,TA15钛合金由下部的柱状晶及上部的近等轴晶组成,中部发生了明显的CET转变,添加Ti2AlNb之后,宏观组织均转变为等轴晶组织。晶内显微组织随着添加Ti2AlNb含量的增加,呈现出α+β→α+α2+β→O+α2+B2的变化规律。在室温拉伸方面,TA15表现出中强高塑的特点,Ti2AlNb合金表现出高强低塑的特点,整体而言,TA15-xTi2AlNb均质材料的强度随着Ti2AlNb含量的增加先减小后增加,同时也根据拉伸断口研究了各组均质材料的断裂机制。Six different mass fraction TA15-xTi2AlNb(x=0%,20%,40%,60%,80%,100%)samples were fabricated by laser solid forming using mixed powders.Microstructure evolution along the depositing direction was investigated.The results shows that the macrostructure of TA15 titanium alloys consists of columnar grains at bottom region and equiaxed grains at top region,obvious CET can be observed at middle.Other samples were comprised of equiaxed grains because of addition of Ti2AlNb.As for microstructure of each sample,with increasing of Ti2AlNb a evolution ofα+β→α+α2+β→O+α2+B2 was presented.As for tensile test at room temperature,TA15 possesses well integrated mechanical property.Tensile strength of TA15-xTi2AlNb increases at first and then decreases with the addition of Ti2AlNb.Fracture mechanism of each sample also was investigated through observing fracture morphology.

关 键 词：激光立体成形 TA15 TI2ALNB 显微组织 力学性能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]