Evaluación de la penetrabilidad de la soldadura láser mediante un modelo analítico

Abstract

An analytical model has been developed for the laser welding

process which, based on multipole theory, predicts the depth

of the weld bead at a very low computational cost. For this,

the model starts from the thermal field previously calculated

considering only the heat transfer by conduction, and includes

the influence of the monopoles, dipoles and quadrupoles,

which allows considering the finite thickness of the sheet to

be welded, the latent heat of the material and the internal

movement of the molten material, respectively.

The model has been experimentally validated for Inconel

718 and the case in which a wobble strategy is used, which

is a combination of linear advance motion and superposed

oscillatory motion resulting in a trochoidal trajectory. For the

different situations analyzed, and thanks to the consideration

of multipole, the model is able to determine the depth of the

weld bead with an error below 12%. This is a considerable

improvement over the situation in which the multipole effect

was not considered and the heat transfer was modelled only by

conduction, since in this case around 50% errors are obtained,

which demonstrates the validity of the model.