药芯组成及工艺参数对ENiCrMo3T0-4药芯焊丝气孔敏感性的影响

Effect of Flux-Cored Ingredients and Welding Parameters on Porosity Sensitivity of ENiCrMo3T0-4 Flux-Cored Wire

采用体式显微镜、优化设计软件研究了ENiCrMo3T0-4药芯焊丝中药芯组成及工艺参数对气孔敏感性的影响。结果表明:随着焊丝药芯组成中SiO_2/ZrO_2、TiO_2/ZrO_2、(TiO_2+ZrO_2+SiO_2)/MnO的减小,气孔敏感性降低;气体流量的改变对焊缝表面针眼气孔数的影响不大,但气体流量过小会产生条虫状气孔;当焊接电压25 V、焊接电流160 A、干伸长量20 mm时,焊缝金属针眼气孔数最少,焊丝气孔敏感性最低;增大固液相温度区间及氢在高温熔渣中的溶解度,可以降低焊缝金属气孔敏感性。

The effect of flux-cored ingredients and welding parameters on porosity sensitivity of ENiCrMo3T0-4 flux-cored wires was investigated by stereomicroscope and optimum design software. Results show that porosity sensitivity is reduced with the ratio of SiO2/ZrO2, TiO2/ZrO2, and（TiO2＋ZrO2＋SiO2）/MnO decreasing in flux-cored ingredients. The shielding gas flow rate has little influence on number of needle holes on weld surface. Wormhole in weld surface is formed when the flow rate is too low. The number of needle holes and porosity sensitivity of weld metal are the lowest when welding voltage is 25 V, welding current 160 A and electrode stick-out 20 mm. Porosity sensitivity of weld metal can be reduced by enlarging solid-liquid phase temperature interval and hydrogen solubility in high temperature slag.