激光——电弧复合焊接头根部特性分析

Study on the root characteristics of laser arc hybrid welding joint

对厚板HQ785T1低合金高强钢填充HS-70焊丝激光—电弧复合焊接头根部化学成分分析及元素线扫描分析,结果表明,焊缝部位主要元素的含量介于母材和焊丝之间,焊缝从上部到根部,随着深度的增加,焊缝元素组成越接近母材,根部焊缝组成以母材成分为主,焊丝成分所占比例较小;焊缝根部冲击韧性低于焊缝上部,增大坡口钝边,焊缝根部的冲击韧性降低;金相显示根部焊缝中心组织为粒状贝氏体组织,随着钝边尺寸的增加,碳化物析出量减少,组织略显粗大,组织脆性增加.

The chemical composition analysis and elemental line scanning analysis of the root of thick plate HQ785T1 steel laser-arc hybrid welding joint filled with HS-70 were studied,the test results show that the element content of the weld is between the base metal and the welding wire,the element composition of the weld seam is closer to the base metal with the increase of the depth.The composition of the root weld is mainly composed of base metal,the proportion of the welding wire is small;The value of the impact toughness is lower than the upper part of the weld,the impact toughness of the weld root decreases with the increase of the blunt edge of the groove;The microstructure of the weld center of the root is granular bainite structure.With the increase of blunt edge size,the amount of carbide precipitation decreases,the microstructure is slightly coarser,and the brittleness increases.