高锰钢堆焊修复用药芯焊丝焊接接头组织性能分析

Analysis on the microstructure and properties of welded joint with flux-cored wire for surfacing repair of high manganese steel

目前高锰钢堆焊修复常用的修复材料是气保护实心焊丝ER309L,但若在线修复时气源无法保障,则不能获得合格焊接接头。文中采用自主研发的自保护药芯焊丝在高锰钢上进行堆焊,通过金相分析、探伤以及力学性能检测等方法,测试并分析了焊接接头的组织与力学性能,并与ER309L焊丝熔覆金属的性能进行对比。试验结果表明:自主研发的自保护药芯焊丝堆焊后着色探伤熔覆金属未见裂纹;光学显微镜下观察热影响区无焊接裂纹,焊接接头抗裂性良好。热影响区在-20℃时的冲击韧度为61.7 J/cm2,ER309L焊丝的熔覆金属在20℃时的冲击韧度为45 J/cm2,由此可知,自保护药芯焊丝焊接接头冲击韧性优于ER309L焊接接头的,该自保护药芯焊丝更适用于高锰钢的在线修复。

At present, the common material for repair of high manganese steel was gas shielded solid cored wire ER309 L. However, if there was no enough gas source during on-line repair to obtain the qualified welded joint. By means of microstructure analysis, penetrant inspection and mechanical properties testing, the microstructure and mechanical properties of welded joints by self-developed self-shielded flux-cored wire were analyzed, and the results was compared with the properties of ER309 L welding wires. The experimental results showed that there was no crack found on the surface of cladding metal obtained by self-shielded flux-cored wire. Moreover, no welding crack was observed in the heat-affected zone by optical microscope. The welded joint had great crack resistance. The impact value of cladding metal under-20 ℃ and ER309 L cladding metal under 20 ℃ were 61.7 J/cm2 and 45 J/cm2 respectively.Therefore, it could be concluded that the impact toughness of the self-shielded flux-cored welded joint was better than that of the ER309 L welded joint. The self-shielded flux-cored wire was more suitable for on-line repair of high manganese steel.