Optimization of laser micro milling of alumina ceramic using radial basis functions and MOGA-II

Abstract

Laser milling provides an efficient method for the fabrication of micro-featured products for a wide range of materials including ceramics by directly importing the design data in various CAD formats. Despite the good process capabilities, research on micro milling for structural ceramics has been given less attention as compared to micro drilling and turning. In addition, most of the studies are limited to factorial analysis. Optimization in terms of multiple objectives and constraints are rare. This paper considers the analysis and optimization of Nd:YAG laser micro milling of alumina ceramic using smooth spline analysis of variance (ANOVA), radial basis functions (RBF), and a multi-objective genetic algorithm (MOGA-II). MOGA-II uses a new smart multi-search elitism operator. It has been found that low surface roughness for micro-milled alumina ceramic is obtained with low frequencies, low pulse overlaps, and moderate intensities. On the other hand, high material removal rates are associated with high laser beam intensities. Optimized solutions are characterized by low and moderate frequencies, high intensities, and medium pulse overlaps.