摘要
采用填丝钨极氩弧焊(GTAW)方法对复层厚度0.3 mm的叠层复合材料与Cr18-Ni8不锈钢进行焊接实验。通过显微图像分析仪和扫描电镜等对焊缝及热影响区的微观组织及显微硬度、元素分布等进行分析。结果表明:叠层复合材料NiCr基层与焊缝形成可靠的熔合,超级镍复层与焊缝过渡区显微硬度升高;不锈钢母材侧形成了明显的重结晶细晶粒区及δ铁素体析出相区;填丝钨极氩弧焊要注意超级镍复层的烧损,应控制焊接电弧偏向不锈钢一侧。
A laminated composite with a thickness of 0.3 mm cover layer and Cr18-Ni8 steel were joined by gas tungsten arc welding(GTAW).Microstructures,micro-hardness,and element distribution in the welded meal and heat affected zone were investigated by micro-image analysis and scanning electron microscopy.It was found that there was a reliable fusion zone between the laminated composite and the weld metal.Micro-hardness in the transition of the cover layer and welded metal increased.Fine grains and δ ferrite precipitation were produced in the welded metal near to the Cr18-Ni8 side.The burning down of the cover layer should be avoided and the welding arc should deflect to the Cr18-Ni8 side during GTAW.
基金
国家自然科学基金资助项目(50874069)
高等学校博士学科点专项科研基金资助项目(200804220020)
关键词
复层材料
镍
不锈钢
熔化极气体保护焊
显微组织
laminated composites
nickel
stainless steel
gas metal arc welding
microstructure