工具头滚花形状对超声波焊接热力学性能的影响

Effect of knurled shape of tool head on thermodynamic properties of ultrasonic welding

建立了考虑材料热软化和声软化效应的3D热力耦合模型,分析锥角形滚花和梯形滚花对双层铜/铜极片超声波焊接温度与塑性形变的影响。通过对比0.1 s内焊接接头的强度变化,建立焊接行为与接头质量的关系。通过红外测温仪及3D光学显微镜分别测量了工件焊接区域的温度及塑性形变,发现焊接试验结果与模拟结果的误差小于10%,表明3D热力耦合模型能够准确预测焊接行为,能够为铜极片超声波焊接提供指导。此外,模拟与试验结果表明,锥角形滚花超声波焊接温度及塑性形变大于梯形滚花的,且锥角形滚花的焊接件强度也优于梯形滚花的,这证明了焊接温度及塑性形变的提高有利于提高工件的焊缝强度,同时表明锥角形滚花工具头更适合铜极片焊接。

A 3D thermo-mechanical coupling model considering the effects of material thermal softening and acoustic softening was established to analyze the effects of cone-angle knurling and trapezoidal knurling on the ultrasonic welding temperature and plastic deformation of double-layer copper/copper pole pieces.By comparing the strength change of the welded joint in 0.1 s,the relationship between the welding behavior and the quality of the joint was established.The temperature and plastic deformation of the welding area of the workpiece were measured by an infrared thermometer and a 3D optical microscope.It was found that the error between the welding test results and the simulation results was less than 10%,indicating that the 3D thermal coupling model could accurately predict the welding behavior and could be used for copper pole piece ultrasound welding provided guidance.In addition,simulation and test results showed that the ultrasonic welding temperature and plastic deformation of cone-shaped knurling were greater than those of trapezoidal knurling,and the strength of cone-shaped knurled welding parts was also better than that of trapezoidal knurling,which proved that the increase in welding temperature and plastic deformation was beneficial to the improvement.The weld strength of the workpiece also showed that the cone-shaped knurled tool head was more suitable for copper pole piece welding.