Optimization of Laser Transmission Welding Process for Thermoplastic Composite Parts using Thermo-Mechanical Simulation

An innovative methodology for the thermo-mechanical simulation of the laser transmission welding (LTW) process for thermoplastic components is presented. The work consists of two parts. In the first part, a finite element (FE) thermal model is developed, for the prediction of the transient spatial temperature history developing during the LTW process. Experimental measurements have been used for the calibration of the developed thermal model. Through this thermal model, a parametric study on the main welding parameters is performed, in order to investigate their effect on the maximum temperature. Using the parametric study results, the optimal combination of the welding parameters is derived taking into account the welding cost. In the second part, the optimized set is used in a model developed for the thermo-mechanical simulation of the LTW process and the calculation of the thermal stresses, strains, and distortions of the welded parts. The benefit of the proposed methodology is that it offers the capability of optimizing the LTW process, and also provides a reliable estimation of the developed temperature, as well as the thermal stress and strain fields reducing the experimental effort.