β锻TC17钛合金力学性能各向异性研究  

Anisotropy of Mechanical Properties of β Processed TC17 Titanium Alloy

作　　者：邓雨亭 李四清 黄旭 Deng Yuting;Li Siqing;Huang Xu(Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys, AECC Beijing Institute of Aero- nautical Materials, Belting 100095, China)

机构地区：[1]中国航发北京航空材料研究院先进钛合金航空科技重点实验室

出　　处：《稀有金属》2018年第8期885-890,共6页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51471155)资助

摘　　要：利用力学性能测试，电子背散射衍射（EBSD）技术、光学显微镜（OM）和扫描电子显微镜（SEM）等，对β锻造TC17钛合金力学性能的各向异性及其影响因素进行了研究。结果表明β锻造TC17钛合金具有明显的力学性能各向异性：不同方向的屈服强度相差115MPa，其中沿轴向加载屈服强度最低，塑性也最差；径向加载屈服强度最高，塑性介于弦向和轴向之间。微观分析后认为原因有以下几个方面：β锻造后合金组织为网篮组织，原始v晶粒沿金属流动方向拉长，不同方向的组织相貌差异较大；室温拉伸断口为韧性断裂，裂纹沿着晶界。相快速扩展；合金中β相形成了强度较强的{001}（100）丝织构，α相形成了强度较弱的{0001}（1120）面织构，其中α相的织构类型与β相符合Burgers取向关系。Anisotropy and influencing factors of β processed TC17 titanium alloy mechanical properties were studied through tensile properties tests, electron backscattered diffraction （EBSD）, metallographic study and scanning electron microscopy （SEM） analysis. Results indicated that tensile properties of beta processed TC17 titanium alloy exhibited obvious anisotropy. Yield strength of different directions differed by up to 115MPa. The axial direction showed the lowest yield strength and ductility, while the radial direction showed the highest yielding strength, and the ductility was between the axial direction and the choral direction. Microstructure analysis results showed that there were following factors which were responsible for the anisotropy of the mechanical properties. Firstly, the original beta grains were elongated and formed into basket-weave microstructure after the beta forging process. Microstructure and morphology were different in three directions. Secondly, the tensile fracture was ductile fracture. The crack rapidly propagated along α phase of the grain boundary. Finally, the β phase displayed a strong {001}〈 100〉 fiber texture and α phase displayed a weak { 0001 } 〈 1120 plane texture. The texture components of transformed α phase were controlled by the parent β phase.

关 键 词：TC17钛合金 Β锻造 力学性能 各向异性 织构 

分 类 号：TG146.2[一般工业技术—材料科学与工程]