辅助外电场电化学控氧对厚板埋弧焊缝性能的影响

Effect of Electrochemical Oxygen Controlled by Auxiliary External Circuit on Performance of Thick Plate Submerged Arc Weld Metal

高端装备制造业的大力发展给埋弧焊焊缝金属质量提出了更高挑战,但往往焊缝金属中氧含量偏高,这又严重地损害了焊接接头的韧性。故研究了在埋弧焊过程中随焊施加辅助外电场电化学对焊缝氧含量的调控及其对力学性能的影响。结果表明:采用辅助外电场法,可有效地抑制焊缝金属增氧;通过观察焊缝金属组织及对夹杂物的形貌和化学成分分析得出,施加外电场作用可提高针状铁素体的比例,增强焊缝金属的韧性储备;低温冲击试验表明,辅助外电场法可使焊缝金属的低温冲击韧性提高45.2%。

The quality of submerged arc weld metal is put forward higher challenge by increasing the development of high-end equipment manufacturing industry, but, the oxygen content in the weld metal is often higher than what it needs, it seriously harms the toughness of the welded joint. So, the effects of electrochemical with applying auxiliary external electric field in the process of submerged arc welding on oxygen content controlled and mechanical properties of welding metal were studied. The results show that the increase of oxygen content in weld metal is restrained effectively by applying an external circuit. The microstructure of weld metal and the morphology of inclusion were observed and the chemical composition of inclusion was analyzed. It＇s shown that the external circuit applied can effectively increase the proportion of acicular ferrite and enhance the toughness of weld metal reserves. In addition, the results of low temperature impact test show that the method of auxiliary external electric field can make the low temperature impact toughness of weld metal increase by 45.2%.