(中国科学院沈阳自动化研究所 机器人学国家重点实验室，沈阳 110016)
摘 要: 基于欧拉-拉格朗日耦合(CEL)方法，建立一个新的搅拌摩擦焊多场耦合计算模型，模拟焊接过程中焊缝区材料的塑性流动与缺陷形成，并通过开展搅拌摩擦焊试验，分别从温度场、焊缝宏观形貌、焊缝截面塑性应变及焊接缺陷几方面对模拟结果的准确性进行验证。结果表明：模拟温度与实测数据吻合较好，最大误差为23.4 ℃；焊缝宏观形貌、焊缝截面塑性应变区的形状和尺寸均与实际焊缝吻合较好；模型能够较准确地预测焊缝内部孔洞缺陷的形成，且缺陷产生的位置与实际位置相吻合，缺陷尺寸的模拟值略大于其实测值。
关键字: 搅拌摩擦焊；材料流动；焊接缺陷；欧拉-拉格朗日耦合方法；数值模拟
（State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China）
Abstract:A new multi-physics coupling numerical model for friction stir welding was established based on coupled Eulerian-Lagrangian (CEL) method. The model was utilized to simulate the material flow and defect formation in the weld during welding. The friction stir welding was conducted to verify the model through the comparison of temperature field, macro morphology of weld, plastic strain in the weld and welding defect. The results show that the simulation temperatures agree well with the measured data and the maximum error is 23.4 ℃. The macro morphology of the weld, the plastic strain zone shape and size on the weld cross-section are in good agreement with the actual weld. The model can accurately predict the formation of void defect in the weld, and the simulated void position is consistent with the actual position. But the void size is overestimated slightly.
Key words: friction stir welding; material flow; welding defect; coupled Eulerian-Lagrangian method; numerical simulation
