焊缝金属强度匹配与扩散氢的关系

Relationships between strength matching and diffusion hydrogen in weld metal

综述了焊缝金属强度匹配与扩散氢的关系。结果表明,常用焊接方法焊缝中氢的来源主要是焊接材料中的水分、坡口杂质及电弧周围的水气等。在焊缝中氢的影响因素中,GMAW方法扩散氢最低,电弧中除氢冶金反应取决于焊接方法,辅助除氢工艺作用不可小觑。高强钢采用低强匹配焊缝时,HAZ形成富氢带,是接头的薄弱环节;采用高强匹配焊缝时,HAZ富氢带不显著,而焊缝中的氢含量高,成为接头的薄弱环节。三种焊缝强度匹配与扩散氢关系的工程应用均获得了满意的工程质量;在马氏体耐热钢及其异种钢焊接中,高强匹配焊缝阻止HAZ形成富氢带的创新理论,尚需深入研究。

The relationships between strength matching and diffusion hydrogen in weld metal were reviewed.The results show that the main sources of hydrogen in the welds of common welding methods are the moisture in welding consumables,impurities in groove and water vapor around arc.Among the influencing factors of hydrogen in weld,the GMAW method has the lowest diffusive hydrogen content,and the metallurgical reaction of hydrogen removal in arc depends on welding method,and the role of auxiliary hydrogen removal process can not be underestimated.When high strength steel is welded with low strength matching weld,the hydrogen-rich zone formed by HAZ is the weak link of the joint;when high strength matching weld is adopted,the hydrogen-rich zone of HAZ is not significant,but the hydrogen content in the weld is high,which becomes the weak link of the joint.The engineering applications of three kinds of relationships between strength matching and diffusion hydrogen in weld metal have achieved satisfactory engineering quality.In the welding of martensitic heat-resistant steel and its dissimilar steel,the innovative theory of high strength matching weld preventing HAZ from forming hydrogen-rich zone needs to be further studied.