激光熔化沉积TC17钛合金光纤激光焊接特性  

Fiber Laser Welding Characteristics of Laser Melting Deposited TC17 Alloy

作　　者：李旭[1] 刘栋[1] 汤海波[1] 张述泉[1] 王华明[1] 

机构地区：[1]北京航空航天大学大型整体金属构件激光直接制造教育部工程研究中心,北京100191

出　　处：《中国激光》2012年第1期109-115,共7页Chinese Journal of Lasers

基　　金：国家973计划(2010CB731705;2011CB606305)资助课题

摘　　要：利用光纤激光对激光熔化沉积TC17钛合金与锻造TC17钛合金薄板进行了激光热导熔化焊接,利用光学显微镜、扫描电镜、X射线衍射仪和显微硬度计分析了接头的组织结构及显微硬度分布。结果表明,TC17钛合金激光熔化沉积件及锻件薄壁板状试样激光焊接接头凝固组织为沿未熔母材外延定向生长的细小树枝晶组织。锻造钛合金焊缝热影响区(HAZ)大且热影响区β晶粒发生了严重的长大现象,而激光熔化沉积钛合金焊缝热影响区小且热影响区β晶粒尺寸几乎无明显变化,表现出优异的焊接热稳定性。无论锻造钛合金还是激光熔化沉积钛合金,其焊缝区显微硬度高于母材,热影响区显微硬度低于母材。Laser melting deposited TC17 alloy and forged TC17 alloy are welded by fiber laser.The microstructure,phase constitution and mechanical properties of the weld joint are studied by optical microscopy,scanning electron microscopy,X-ray diffraction and microhardness tests.Results indicate that the fusion zone（FZ） mainly consists of fine dendrite which nucleated and epitaxially grows from the substrates.The heat input makes the β grain of forged TC17 grow more seriously than that of laser melting deposited TC17.The heat affected zone（HAZ） of laser melting deposited TC17 is much narrower than that of forged TC17.Laser melting deposited TC17 exhibits better thermal stability than forged TC17.The microhardness of FZ is higher than that of the base metal,and the microhardness of HAZ is lower than that of the base metal.

关 键 词：激光技术 材料 焊接特性 激光焊接 激光熔化沉积 

分 类 号：TG456.7[金属学及工艺—焊接]