Author(s)

R. Gospavic & V. Popov

Abstract

In this work an analytical approach for analysis of surface treatment by a laser beam is presented. A thermal model of interaction for the case of cylindrical geometry of the material and asymmetric distribution of the laser beam intensity are used. An analytical procedure is developed to analyze the temporal and the spatial distribution of the temperature field inside the bulk of material. This kind of consideration is of practical interest in cases where the excitation by the laser beam is not symmetric in respect to its position or shape, e.g. multi-mode working regimes or asymmetrical distribution of the laser beam intensity. The heating effects were considered in the temperature range up to the melting point. The thermal and the optical parameters of the material were assumed to be independent of the temperature and were given constant values in the temperature range of interest. This approach makes use of the Laplace transform, in order to eliminate dependence on time. The Fourier method of variable separation was used to obtain the temperature field distribution in the Laplace transform domain. Keywords: surface treatment, laser, thermal model, multi-mode. 1 Introduction In a general case the analysis of the laser-material interaction, important for practical applications, is very complex and includes analysis of different physical processes such as material removal, material melting, thermal stresses, shock wave, etc. This prevents successful construction of a general analytical solution and different numerical procedures have been used in the past [1]. This work is restricted only to analysis of heating effects of the laser-material interaction.

Keywords

surface treatment, laser, thermal model, multi-mode.