TC4钛合金中厚板激光焊接接头组织及性能研究  

Study on Microstructure and Properties of Laser Welded Joint of TC4 Titanium Alloy Medium Plate

作　　者：刘甲 雷小伟[1] 余巍[1] 马照伟 符成学 崔永杰[1] 杜志博 王伟超 LIU Jia;LEI Xiaowei;YU Wei;MA Zhaowei;FU Chengxue;CUI Yongjie;DU Zhibo;WANG Weichao(Luoyang Ship Material Research Institute,Luoyang 471039,China)

机构地区：[1]中国船舶重工集团公司第七二五研究所,河南洛阳471039

出　　处：《热加工工艺》2023年第11期19-24,共6页Hot Working Technology

基　　金：郑洛新自创区专项资助项目(201200211400)。

摘　　要：分析了16 mm厚TC4钛合金板的激光焊接技术,研究了辅助气体侧吹对激光深熔焊成形的影响规律,然后在此基础上实现了16 mm厚TC4板的一次焊透、双面成型。对激光焊接试板开展了金相组织分析,测试了接头的拉伸、显微硬度、冲击及弯曲等性能。试验结果表明:TC4激光焊接焊缝组织主要为针状α’相、马氏体α、少量针状α和β相,可以看到粗大的高温β相晶界,热影响区由针状α’相、块状α相、马氏体α、少量β相组成,部分区域针状α’相+β相呈现网篮特征。接头平均抗拉强度为965 MPa,为韧性断裂;母材平均显微硬度值最低,焊缝和热影响区域硬度值相近,形成典型的“软+硬+软”三明治式硬度分布结构;焊缝和热影响区冲击吸收功值相近,母材冲击吸收功最低,焊接接头弯曲性能良好。The laser welding technology of 16 mm thick TC4 titanium alloy medium plate was studied.The influence of auxiliary gas blowing on the laser penetration welding was studied firstly,and based on the above study,the single pass penetration welding with two sides forming of 16 mm thick TC4 plate was realized.The metallographic structure of the laser welded joint was analyzed,and the tensile,microhardness,impact and bending properties of the joint were tested.The results show that the welded zone is mainly composed of needle α',martensiteα,a small amount of needle α and β phases,coarse high temperature β phase boundary can also be observed,the heat affected zone is mainly composed of needleα',block α,martensiteαand a small amount of β phase,in partial area the needle α' and β phases present network characteristics.The average tensile strength of the joint is 965 MPa,the tensile fractures are ductile rupture.The average hardness of the material is the minimum,the average hardness between the heat affected zone and the weld zone is similar,and a typical"soft+hard+soft"sandwich hardness distribution structure is formed.The absorbing work between the weld zone and the heat affected zone is similar,the average impact absorbing work of the base material is the minimum,and the bending property of the welded joint is good.

关 键 词：TC4钛合金 激光焊接 微观组织 力学性能 

分 类 号：TG456.7[金属学及工艺—焊接]