Studies for Laser Densification of Ceramic Coating

Abstract

A mathematical analysis describing the densification of ceramic coating processed with a moving TEM₀₀, mode laser beam has been presented in this paper. Calculations of the depth of the heat affected zone in ZrO₂, A1₂O₃ and TiO₂ ceramic substances is performed by adopting a three-dimensional quasi-steady state heat conduction model based on the mechanism of viscous solid-phase densification. Also, a working range for these ceramics coating densification is predicted by varying the laser beam power, spot size and scanning velocity. The heat-affected layer in ZrO₂ compact is found to be confined within a depth of 50 μm from the surface and it is fully densified for grains of initial radius 5 μm. A simple expression for temperature distribution is presented, which is found to provide sufficiently accurate estimates within a limited region around the laser spot.