Thermal characterization of resistance spot welding

This work consists of estimating simultaneously the thermophysical parameters which characterize the thermal behavior of two solids in combined thermal and electrical contact, i.e., the heat flux released at the interface, the partition coefficient of this heat flux, and the thermal contact conductance between the two solids. The parameter estimation problem is performed with the Levenberg-Marquardt method. A detailed analysis of the linear dependency of the contact parameters needed to design a robust estimation tool is presented. Despite a weak correlation between the partition coefficient and thermal conductance, the results show that the estimation is feasible and the method developed is an effective tool for a complete thermal characterization of the contact interface. The article concludes with an elementary Monte Carlo study to validate the developed method for estimating the confidence intervals.