In the present paper, the laser beam weldability of ABS plates is determined by combining
experimental and theoretical aspects. In modelling the process, an optical model is used to determine
how the laser beam is attenuated by the first material and to obtain the laser beam profile at the
interface. Using this information as input data in a thermal model, the evolution of the temperature
field within the two components can be estimated. The thermal model is based on first principles of
heat transfer and utilizes temperature variation laws of material properties. Corroborating the
numerical results with the experimental ones, some important insights concerning the fundamental
phenomena that govern the process could be extracted. This approach proved to be an efficient tool in
determining the weldability of polimeric materials and assures a significant reduction of time and costs
with the experimental exploration, this one being made only for finding the optimal values