Evaluation of surface cracks following processing of a ZrO₂ advance ceramic with CO₂ and fibre laser radiation

This research examines the thermal shock know as cracking on a ZrO₂ advance ceramic (ZAC) during fibre and CO₂ laser surface engineering (LSE). A parameter window was designed and the effects of both the fibre and the CO₂ lasers were compared upon the specific ZrO₂ ceramic type used herein. Unlike previous studies, no pre-or-post heating techniques for the surface engineering process were adopted since such methods are a non-value adding feature to the laser surface treatment process. A threshold with minimal or no surface cracks was found for the ZAC during both the CO₂ and fibre laser surface engineering. The best laser processing parameter window for the type of ZAC used herein was presented for both the CO₂ and the fibre LSE. In addition, laser processing temperatures were measured to compare the heat distribution of both the CO₂ and the fibre laser to further justify the influence of the thermal shock induced thereof on the ZAC. The result from this study can be adopted to further improve laser based processes such as laser surface treatment and laser assisted sealing of hard to process materials such as advance ceramics.