电弧能量匹配对前后列置双TIG高速焊接焊缝组织与性能的影响

Microstructure and properties of weld by high-speed tandem TIG welding of different arc power matching

对厚度为1.2 mm的304奥氏体不锈钢板进行前后列置双TIG电弧高速焊接工艺试验,通过对焊缝宏观形貌、组织和拉伸性能进行分析,评定前置电弧能量和后置电弧能量大小匹配对焊缝组织与性能的影响.结果表明,前置电弧能量较高的焊缝中心晶粒平均直径相比母材降低约33.9%,相比后置电弧能量较高的焊缝中心晶粒平均直径降低约26.1%,热影响区晶粒平均直径降低约18.1%.前置电弧能量较高焊缝相比后置电弧能量较高的焊接标准试样抗拉强度提高约7.9%,断后伸长率提高约33.3%,说明前置电弧能量较高有助于获得较高性能的焊缝.

The experimental materials were 304 austenite stainless steel plates, with 1.2 mm in thickness.According to the analysis of the weld appearance, and the microstructures and properties of the weld joint, the quality of the weld beads at different parameters was obtained. The experimental results show that the average grain size at higher leading arc power of weld center is about 33.9% lower than that of the base metal. Meanwhile, the average grain size of HAZ is reduced by about 18.1% compared with higher rear arc power. The tensile strength of the weld is higher than that of the standard specimens with higher rear arc power, by 7.9%,and the elongation is higher than that of higher rear arc power,by 33.3%. It indicates that the weld at higher leading arc power behaves better properties.