Quantitative evaluation of the quality of the cuts performed on mullite-alumina by Nd:YAG laser

Mullite-alumina is an advanced ceramic with great importance in the construction of structural elements for high temperature applications. The inherent properties of this material such as its very high hardness and brittleness make conventional machining a very hard task, being slow, noisy and poor productive. In this paper we present the results of the work carried out to investigate the influence of different cutting parameters on the laser cut quality. Specifically, a detailed study of the characteristics of the heat affected zone (HAZ) is presented as a function of average laser power, cutting speed, assist gas pressure and pulse frequency. Quantitative analysis of the HAZ characteristics was performed by means of analytical image processing of dimensional magnitudes easily identified in the optical microscopy images. (C) 2003 Elsevier Ltd. All rights reserved.