摘要
采用Nd:YAG激光器进行TC4钛合金与50钢异种材料激光焊接,研究了接头的裂纹扩展与焊缝的微观组织以及物相成分。结果表明,裂纹类型及位置与工艺参数有关。裂纹在焊缝中以穿晶的方式进行扩展,接头断裂为脆性断裂。焊缝中有高碳马氏体的形成,高碳马氏体有中脊存在。焊缝中的Ti-Fe相为TiFe、TiFe2金属间化合物,并且TiFe数量多于TiFe2。高碳马氏体与TiFe、TiFe2金属间化合物的高硬度以及差的韧性与塑性是裂纹萌生与扩展的主要原因。
TC4 titanium alloy was welded with 50 steel by Nd: YAG laser. The crack propagation, microstructure and phase composition of the joint were studied. The results show that the crack type is related to the position and process parameters, and the crack propagation in the weld is transgranular, and the joint fracture is brittle fracture. The high carbon martensite formed in the weld and the middle ridge existed in the high carbon martensite. Ti-Fe phase in weld seams is TiFe, TiFe2 intermetallic compound, and the number of TiFe is higher than TiFe2. High hardness and poor toughness and plasticity of high carbon martensite and TiFe and TiFe2 intermetallic compounds are the main causes of crack initiation and propagation.
作者
刘孟晗
方正帅
刘凤德
张宏
Liu Menghan;Fang Zhengshuai;Liu Fengde;Zhang Hong(College of Mechanical and Electric Engineering,Changchun University of Science and Technology,Changchun,Jilin 130022,China)
出处
《应用激光》
CSCD
北大核心
2021年第3期474-480,共7页
Applied Laser
基金
吉林省科技发展计划项目(20190302022GX)。
关键词
异种材料
激光焊接
穿晶扩展
高碳马氏体
金属间化合物
dissimilar materials
laser welding
transgranular extension
high carbon Martensite
intermetallic compounds
