Y掺杂及真空热压烧结对TiAl基合金显微组织和力学性能的影响（英文）  

Effect of Y Doping and Vacuum Hot-Press Sintering on Microstructure and Mechanical Properties of TiAl-based Alloys

作　　者：李阳[1] 孙红亮[1] 杨康[1] 邓鹏[1] 陈志元 Li Yang;Sun Hongliang;Yang Kang;Deng Peng;Chen Zhiyuan(Southwest Jiaotong University, Chengdu 610031,China)

机构地区：[1]西南交通大学

出　　处：《稀有金属材料与工程》2019年第6期1756-1761,共6页Rare Metal Materials and Engineering

基　　金：National Key Basic Research and Development Program of China(2016YFB1200505)

摘　　要：Ti-45Al和Ti-45Al-0.3Y(at%)样品通过真空热压烧结的方法制备。样品通过X射线衍射(XRD)、光学显微镜(OM)、背散射电子成像(BSE)以及压缩和硬度测试来研究Y掺杂和热压工艺参数对TiA l基合金的显微组织和力学性能的影响。结果表明,最优烧结参数为压力42 MPa,1400℃下保温保压90 min。在此参数下,得到了组织均匀、晶粒细小的由γ相和γ+α2片层结构组成的双态组织。在热压温度1400℃,保温时间240min下,反应充分但会出现晶粒粗大现象。Y的加入对细化晶粒和片层间距有明显的影响,这有助于提高合金的机械强度。Ti-45Al and Ti-45Al-0.3Y(at%) samples were fabricated by vacuum hot-press sintering(VHPS). The influence of Y addition and VHPS process parameters on the microstructure and mechanical properties of TiAl-based alloys were analyzed using X-ray diffraction(XRD), optical microscopy(OM), back-scattered electron(BSE) imaging, compression and hardness testing. The results show that optimized sintering parameters are 42 MPa at 1400 °C with holding time of 90 min. Samples prepared under optimized conditions have uniform and fine grains and duplex microstructure consisting of γ phase and γ+α2 lamellar colonies. The reaction between γ-TiA l and α2-Ti3Al reaches completion at a hot-press temperature of 1400 °C for a holding time of 240 min, while significant grain growth occurs under these conditions. The addition of Y has an obvious effect on the refinement of grain and interlamellar spacing, which contributes to an increased mechanical strength of the alloy.

关 键 词：真空热压烧结 Y掺杂 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] TG306[金属学及工艺—金属材料]