摘要
利用双侧激光同步焊接的方法获得TC4合金T形接头,对接头进行光学显微组织观察以及拉伸性能测试,分析了接头的显微组织与力学性能。结果表明,T形接头母材显微组织为α+β等轴组织。焊缝区显微组织由粗大的β柱状晶和网篮状马氏体组成,蒙皮侧焊缝区柱状晶和马氏体晶粒比加强筋侧细小。热影响区显微组织由细小的针状马氏体、针状α相和少量等轴初生α相组成,蒙皮侧热影响区比加强筋侧窄。T形接头焊缝区拉伸强度大于母材,接头拉伸断裂均发生在离焊缝中心较远的母材上。
TC4 T-joints are welded by using double-sided laser beam welding, and the microstructure characteristics and mechanical properties of the welded joints are investigated using optical microscope observa- tion and tensile testing. The results show that the micro- structure of base metal is α＋β equiaxed structure. The microstructure of weld seam is composed of coursed β columnar crystals and basket-like martensite, and the size of β grains and martensite of weld seam near skin are finer than that near stringer. The microstructure of heat affected zone is consisted of needle martensite α, aciculate α and little primary ct phase, and the heat affected zone near skin is smaller than that near stringer. Meanwhile, the tensile strength of weld seam is higher than base metal. The frac- ture occurs on the base metal away from the weld seam during the tensile tests of the joints.
出处
《航空制造技术》
2015年第17期104-106,109,共4页
Aeronautical Manufacturing Technology
关键词
钛合金
双光束激光焊
T形接头
显微组织
拉伸性能
Titanium alloy Double-sided laserbeam welding T-joints Microstructure Tensileproperties
