【摘要】 对国产药芯焊丝 YJ5 0 7和 YJ5 0 2进行了焊接工艺试验 ,观察了药芯焊丝熔敷金属的显微组织 ,分析了药芯焊丝的熔敷金属化学成分。进行了药芯焊丝所焊焊接接头的低温冲击试验及焊接接头的常温拉伸试验。结果表明 ,国产药芯焊丝 YJ5 0 7和 YJ5 0 2具有良好的焊接工艺性能 ,其熔敷金属扩散氢含量较低 ;YJ5 0 7药芯焊丝的熔敷金属中含有一定量的镍 ,细化了先共析铁素体 ,提高了其低温韧性 ;YJ5 0 2药芯焊丝的熔敷金属含有一定量的钛和硼 ,易于形成针状铁素体 ,从而提高其低温韧性。更多还原

【Abstract】 In order to weld the low temperature steel and to develope the flux-cored wire in China, the welding experiments were carried out by the flux-cored wire YJ507 and YJ502 which where made in China. The deposited metal microstructures of the flux-cored wire YJ507 and YJ502 were observed . The chemical composition of the deposited metal was tested. The diffusion hydrogen contents of the deposited metal of the flux-cored wire YJ507 , YJ502 and the E70T-5, E70T-1 which were made in USA were tested and the results were compared to each other. The impact toughness experiments and the tensile strength experiments of the weld joints welded by the flux-cored wire YJ507 and YJ502 were carried out . The experimentd results show that the flux-cored wire YJ507 and YJ502 have a good appearance in welding process, the diffusion hydrogen contents of the deposited metal of the flux-cored wire YJ507 and YJ502 are lower than one of the E70T-5 and E70T-1, the deposited metal of YJ507 contains Ni and the fine ferrite is formed, therefore the impact toughness of the weld joints welded by the flux-cored wire YJ507 is improved. The experiment results also show that the deposited metal of YJ502 contains Ti and B and the needle ferrite is formed , the impact toughness of the weld joint welding by the flux-cored wire YJ502 is improved. The flux-cored wire YJ507 and YJ502 are suitable to weld the low temperature steels and some important steel structures.更多还原