Modelling of laser induced surface modification of ceramic substrates

Abstract
A laser supported process has been developed to modify the electrical and thermal properties of ceramic substrates locally. This process is characterised by a strong thermal interaction between the laser beam and the ceramic surface which leads to localised melting. During the dynamic melting process an additional metallic material is introduced. After the solidification a metal-ceramic composite has been generated with different physical properties compared to the non-modified ceramic. The heat and mass transfer during this dynamic melting and solidification process has been studied experimentally and also numerically in order to identify the dominating process parameters. Simulation tools based on a finite element model have been developed to describe the heat transfer, fluid flow and the phase change during the melting and solidification of the ceramic. The results of the calculation have been validated against experimental results.