In order to investigate the weldability of Q390 steel further and master the residual stress distribution of the welded joint with various welding technology, Q390 HSLA steel plate with the thickness of 40 mm were welded by shielded metal arc welding and submerged arc welding respectively. The surface residual stress of specimens welded was measured by blind-hole method. The residual stress distribution characteristics perpendicular to the welded joint were obtained. The results showed that the deformation of the specimen could be reduced effectively by using submerged arc welding combined with external restraints, and compress stress was obtained in welded joint. There was a large deformation in the specimen welded by shielded metal arc welding without external restraints, and a large tensile stress was located in weld, but compress stress was got in fusion zone and HAZ.%为了深入研究Q390钢焊接性能,掌握其在不同焊接工艺条件下焊接接头残余应力分布规律,对40 mm厚Q390低合金高强度结构钢板分别采用埋孤焊和焊条电孤焊2种焊接工艺进行焊接,采用盲孔法测量了焊态下焊接试板的表面残余应力,得到了垂直于焊缝的残余应力分布曲线.结果表明:采用埋弧焊通过施加外在约束可以有效减小焊后试板变形,在焊接接头处得到压应力;经焊条电弧焊自由焊接条件下试板变形较大,在焊缝区得到拉应力,在熔合区和热影响区得到压应力.
展开▼
