多点凸焊熔核形成过程数值模拟及应用

Simulation of nugget formation process in multi-points projection welding and its application

建立了多点电阻凸焊过程的热电耦合ANSYS模型,指出了在多点凸焊过程中电流出现明显的分流现象.发现了在通电焊接的过程中,受温度和压力综合影响,上工件与下工件的接触点电流密度最大,两侧电流密度值则呈明显下降趋势.并以金属波纹填料凸焊过程为应用实例,对该过程热学和电学行为进行了定量的分析.结果表明,在0.17 mm厚的304不锈钢孔板波纹填料板的凸焊过程中,数值模拟得到的不同时刻熔核温度场、熔核尺寸与实测结果吻合良好,此方法可为多点凸焊工艺参数设计和优化提供理论依据.

Firstly,the thermo-electric coupling ANSYS model of multi-points projection welding is built up and the results reveal that the current has an apparent diversion phenomenon at different projection points.Due to the combined effects of temperature and pressure,the values of current density in the middle of contact points between the upper and lower workpieces are maximal and decrease distinctly on both sides.Then the thermal and electrical behavior of the metal corrugated plate packing with 0.17 mm thickness 304 stainless steel is quantitatively analyzed in the process of projection welding.Meanwhile,the temperature field in the nugget formation process has been obtained.The sizes of nugget obtained by numerical simulation are in good agreement with the measured results.Therefore,this method provides a theoretical basis for the design and optimization of the parameters in multi-point projection welding process.