非对称角根焊熔透和焊后变形的规律

T形角接单侧开V形坡口的中厚板焊接具有成本低、生产效率高的特点，但这种焊缝两侧结构非对称，尤其根部结构厚度悬殊，焊接热传导差异大，不易有效保证良好全熔透成形，且焊后工件常伴随变形较大，影响后续安装使用. 为了获得非对称焊缝焊接热输入对熔透和变形的作用机制，提出考虑热输入大小和能量分配两个因素探讨对热传导规律的影响. 在温度场模拟中引入了等效双高斯热源模型，有效提升了计算精度. 采用数值模拟和试验相结合的方法，对熔透成形、应力场分布和焊件变形进行了对比分析. 结果表明，当焊接电流保持不变且焊枪角度为20°时，焊件变形量最大，焊接试件变形增加18%左右；当焊枪角度一定时，焊件变形量随焊接电流的逐渐增加而增大，最大变形量为2.595 2 mm. 相关研究揭示了非对称焊缝熔透和焊接变形规律，为此类非对称角根焊的焊接质量工艺参数优化提供理论支持.

Law of penetration and post-weld deformation of asymmetric fillet root welding

Medium plate with T-fillet joints and one-side V-shaped grooves has the characteristics of low cost and high production efficiency. However, the two sides of the weld are asymmetrical, especially the thickness of the root structure is very different, and the welding heat conduction difference is uneven, so that the good full penetration forming is not easy to effectively guarantee, and the workpiece is often deformed after welding, which affects installation. In order to figure out the mechanism of welding heat conduction of asymmetric welding on penetration and welding deformation, the influence of energy distribution and the size of heat input on the heat conduction is considered. The equivalent Gauss heat source model is introduced in the temperature field simulation, which effectively improves the calculation accuracy. The method of simulation and experiment was used to analyze the penetration formation, stress field distribution and welding deformation comparatively. The results show that when the welding current is the same and the welding torch angle is 20°, the welding deformation is larger and the deformation of the base metal is increased by about 18%. When the welding torch angle is constant, the welding deformation increases with the increase of the welding current, and the maximum deformation is 2.595 2 mm. The relevant research reveals the law of asymmetric weld penetration and welding deformation, which provides theoretical support for the optimization of welding quality and process parameters of this kind of asymmetric fillet welding.