搅拌摩擦焊焊接温度数值模型及其影响因素

通过对搅拌摩擦焊过程进入稳定状态后摩擦产热与散热机制的分析,建立了搅拌摩擦焊焊接温度的数值模型。由数值模型可知,影响焊接温度的各种因素包括被焊材料和搅拌工具材料的物理性质、两者之间的摩擦因数、搅拌工具的尺寸、焊接参数、被焊材料表面受到的轴向压力和侧面受到的进给压力等,有些因素之间还互相影响,关系复杂。其中,搅拌工具的旋转速度、搅拌工具与被焊材料之间的摩擦因数、被焊材料表面受到的轴向压力及侧面受到的进给压力是主要因素。以聚氯乙稀板材搅拌摩擦焊为例,验证了在适当的取值范围内焊接温度数学模型的理论计算值与实测值基本吻合。

NUMERIC MODEL OF WELDING TEMPERATURE IN FRICTION STIR WELDING AND AFFECTING FACTORS

Based on the analysis of the balance of heat generating and dispersing after the friction stir welding (FSW) procedure being steady, the numeric model of welding temperature is established. It can be seen that a lot of influencing factors on the temperature are enclosed, such as the physical natures of the welded material and the material of stir tool, the friction coefficient between the two sliding materials, the dimensions of the stir tool, the welding parameters, the pressure on the surface and on the side face of welded plate etc. The relationships between some factors are complex, being affected by each other. The principal factors are rotation speed of stir tool, friction coefficient between the stir tool and the workpiece, the pressure on the surface and on the side face of welded plate. The validity of the model is testified by FSW on PVC plate. The calculated welding temperature is considerably identical with the measured one provided some parameter values are taken in a suitable range.