TIG电弧增材制造TC4钛合金的组织与性能  

Microstructure and Properties of TC4 Titanium Alloy Produced by TIG Arc Additive Manufacturing

作　　者：魏志祥 李国选 汪月勇 王超宁 汪奇鹏 孔见[1] WEI Zhixiang;LI Guoxuan;WANG Yueyong;WANG Chaoning;WANG Qipeng;KONG Jian(School of Materials Science and Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;China State Shipbuilding Corporation Jiujiang Zhongchuan Fire Fighting Equipment Co.,Ltd.,Jiujiang 332000,China)

机构地区：[1]南京理工大学材料科学与工程学院,南京210094 [2]中国船舶工业集团九江中船消防设备有限公司,江西九江332000

出　　处：《有色金属工程》2021年第10期14-19,63,共7页Nonferrous Metals Engineering

基　　金：国防基础科研计划资助项目(JCKY2017206B002)。

摘　　要：对TC4钛合金TIG电弧增材的组织与性能进行了研究。结果表明:电弧增材TC4钛合金显微组织与电弧增材钢铁材料的铸态特征不同,具有显著的热处理态特征,是由α和β两相构成的网篮组织。分析其形成过程可以发现,增材体初生组织为枝晶,此时具有明显取向;在后续增材过程多次再热的作用下,由于钛的导热性较低,增材体维持较高的温度,枝晶成分逐渐均匀化,转变为各向异性的细长的β晶粒;随后温度降低,转变为α和β两相网篮组织,且α相处于过饱和状态,可观察到纳米级点状析出的β相,此时组织与性能接近各向同性,室温抗拉强度可达998 MPa,断后伸长率可达8.7%。The microstructures and properties of TC4 titanium alloy prepared via TIG arc additive manufacturing were studied.The results show that the microstructure of the arc additive manufacturing TC4 titanium alloy is different from the as-cast characteristics of the arc additive manufacturing steel material,which has significant heat-treated characteristics.It is a basketweave structure composed ofαandβphases.Analyzing the formation process,it can be found that the primary structure of the additive body is dendrites,which has obvious orientation at this time;with the action of multiple reheating in the subsequent additive process,since the low thermal conductivity of titanium,the additive body maintains a higher temperature,the dendrite composition gradually becomes uniform and transforms into anisotropic slenderβcrystal grains;then the temperature decreases and transforms into a two-phase basketweave structure ofαandβ,and theαphase is in a supersaturated state,theβ-phase precipitated with nano-scale dots can be observed,the structure and performance is close to isotropic at this time,the tensile strength and the elongation after fracture at room temperature can reach up to 998 MPa and 8.7%,respectively.

关 键 词：TC4钛合金 电弧增材制造 显微组织 力学性能 

分 类 号：TG146[一般工业技术—材料科学与工程]