摘要
采用填丝钨极氩弧焊(TIG)方法对复层厚度仅0.3mm的叠层复合材料与18-8不锈钢进行焊接.通过显微图像分析仪、电子探针(EPMA)和X射线衍射仪(XRD)等对焊缝微观组织、显微硬度和熔合区附近相组成等进行分析.试验发现,焊缝边缘处的奥氏体晶粒生长具有方向性,呈柱状晶形态垂直于熔合区生长;叠层复合材料NiCr基层与焊缝形成可靠的熔合,Super-Ni复层与焊缝过渡区显微硬度升高;18-8钢侧焊缝显微硬度低于不锈钢母材.结果表明,焊接区主要是奥氏体、少量δ铁素体、γ-Ni(Cr,Fe),FeNi等物相;焊接中应使钨极氩弧偏向18-8钢一侧,以避免镍复层过度烧损.
Super-Ni laminated composite and 18-8 stainless steel were welded together by tungsten inert gas arc welding with filler metal. Microstructure, microhardness and phase constitution near the fusion was analyzed by means of micro-image analyzer, electron probe micro-analyzer and X-ray diffraction. Experimental results indicated that the columnar austenite grains at the weld edge grew with directionality, which were perpendicular to the fusion zone. A reliable fusion zone was formed between the NiCr base layer and the welded metal. Microhardness near the super-Ni cover layer increased, while the microhardness of welded metal near the 18-8 steel was lower than that of the 18-8 base metal. The welded metal mainly consisted of austenite, a little δ ferrite, γ-Ni (Cr, Fe) and FeNi. The tungsten arc in the welding should be controlled towards the 18-8 steel side to avoid the excessive molten lose of super-Ni cover layer.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2010年第2期13-16,共4页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(50874069)
高校博士点基金资助项目(200804220020)
关键词
叠层复合材料
异种材料
焊接
组织结构
钨极氩弧焊
laminated composite
dissimilar material
welding
microstructure
tungsten inert gas arc welding
