V对MGH956合金TIG原位合金化焊接接头组织与性能的影响  

Effects of V on Microstructure and Properties of MGH956 Alloy Welding Joints with TIGIn-situ Alloying

作　　者：罗雅[1] 雷玉成[1,2] 龚晨诚 梁申勇[1] 

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]江苏省高端结构材料重点实验室,江苏镇江212013

出　　处：《材料工程》2015年第1期59-65,共7页Journal of Materials Engineering

基　　金：国家自然科学基金资助项目(51075191);江苏省高校博士创新基金项目(CXZZ11_0556);江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：为改善MGH956合金TIG焊焊缝的组织与性能,采用原位合金化方法对该合金进行TIG焊接。对比不同含量V的填充材料对焊缝组织与性能的影响,并讨论了V的作用机理。OM和SEM结果表明:填充材料中添加不同含量的V后,组织出现了不同程度的细化及均匀化,当wV=1.5%时,晶粒最细、尺寸均匀,同时焊缝中的气孔量有所减少;对焊缝中的颗粒进行物相鉴定可知,除了有YAlO3,TiC和TiN颗粒生成外还有(Ti,V)C复合颗粒生成。由TEM观察显示wV=1.5%时,焊缝内的碳化物颗粒与焊缝基体结合良好,且wV=1.5%时,接头强度最高,并实现了接头断裂方式由完全脆性断裂转变为韧性断裂。In order to improve the microstructure and properties of MGH956 alloy TIG weld, the alloy was welded with TIG in-situ alloying. The effects of V on the microstructure and properties of MGH956 alloy weld were studied, and the mechanism of V was discussed. The OM and SEM results show that the microstructure of the welds are refined and homogenized with different content of V added in the consumables, and as Wv = 1.5 %, the grain size is the smallest and the most uniform. At the same time the weld porosity is the lowest. The EDS results show that there are （Ti, V） C parti- cles generated in addition to YA103, TiC, TiN particles in the weld. It can be observed by TEM that the interface between carbide particles and the matrix is clean and joins well. The strength of the weld is the highest when ωv= 1.5%, and the fracture mode of the joints changes from complete brittle fracture to ductile fracture.

关 键 词：MGH956合金 原位合金化焊接 V 组织 性能 

分 类 号：TG132.3[一般工业技术—材料科学与工程]