【摘要】 根据能量守恒的基本原理和钨极氩弧焊(TIG)工艺的特点,建立了运动电弧作用下紫铜的三维非稳态TIG焊接熔池形态的数值分析模型,分析中引入了热焓的概念和表面双椭圆分布的热源模型,较好地满足了TIG焊接数值模拟的要求.针对紫铜焊接性较差的特点,在不预热的情况下采用Ar+N2混合保护气体对厚壁紫铜进行了TIG焊接的研究.试验结果表明电弧的热效应显著提高,实现紫铜的不预热TIG焊接是可行的.同时在不同工艺参数条件下对TIG焊接温度场进行了研究,建立了不同的工艺参数与熔深和熔宽之间的关系.并且将计算值与试验值进行了比较,结果表明计算结果与实际测量的结果较为吻合,证明了模型的可靠性和正确性.更多还原

【Abstract】 According to energy conservation principle and characteristics of tungsten inert gas（TIG）, the numerical model of non-steady TIG welding pool shape under moving arc was established. By introducing the heat enthalpy conception and the heat model of surface bielliptic distribution, the demands for welding numerical simulation was fairly satisfied. To improve the welding performance of copper, TIG welding of thick-wall red copper adopting Ar+N₂ without preheating was studied.The experimental result shows that welding arc’s heating effect is evidently increased and it is feasible to realize TIG welding of red copper without preheating. The experiment value and the calculation value under different parameters are compared. The relation between different parameters and welding width and depth is established. The results show the agreement between the model and the experiment.更多还原