直流电阻对焊接头变形和界面污物清除率研究

采用塑性变形理论和刚粘塑性材料模型研究了直流电阻对焊接头的塑性变形。建立了焊接接头变形区域内材料质点速度场和位移场的数学模型，导出了计算接头变形及接合界面污物清除率的公式。对焊接条件下接头的塑性变形和界面污物清除率进行了计算，并与实际接头外形进行了比较。结果表明，计算所得接头变形与实际接头变形基本相符，所得模型能较好描述塑性区内质点的运动规律。界面质点的运动规律也与试验研究结果相符。

Study on the Joint Deformation and the Interface Contaminant Ejection Rate in DC Upset Butt Welding

The joint deformation of DC upset butt welding was studied by using theory of plastic deformation and rigid-viscosity plastic material model. The mathematic models of the velocity and the displacement fields for metal particles within the interface plastic zone were obtained. The formula, which could be used to calculate the deformation and the interface contaminant ejection rate of the DC upset butt welding joint, was deduced from the displacement field. Then, the deformation and the interface contaminant ejection rate were calculated under welding conditions, and compared with the real joints. The results show that the calculated shape corresponds with the real joint shape, and the movement of the particles at the interface corresponds with the real situation.