【摘要】 针对钎剂影响钎焊接头腐蚀性的问题,采用超声波钎焊技术,成功实现了大气环境中AZ31B镁合金板无钎剂搭接.分析了超声振动钎焊接头微观结构及力学性能,研究了超声振动时间和钎缝预留间隙对钎焊接头抗剪强度的影响.结果表明,超声振动可有效去除母材表面氧化膜;在适当的振动时间范围内,接头抗剪强度可达80～90MPa;钎缝预留间隙过大或过小,接头抗剪强度下降;接头显微组织主要为α-Mg固溶体和Mg-Zn相,接头断裂方式主要为沿晶断裂.更多还原

【Abstract】 In order to solve corrosion problem of soldered joint when fluxing agents were used,a technology of ultrasonic soldering was developed.A lap joint of magnesium alloy AZ31B was obtained successfully in air with ultrasonic aided.The microstructure and strength of the joint soldered by this method were studied.The effect of ultrasonic vibration time and width of clearance on shear strength of joint was investigated.The results indicated that ultrasonic vibration can remove the oxide layer on base metal.And the shear strength of joint reaches 80-90 MPa in the appropriate range of vibration time.The shear strength decreases when the width of clearance is too large or too small.The microstructures of joint are mainly α-Mg and Mg-Zn phases and the fracture mode is intergranular fracture.更多还原