Development of statistical model to predict Ra and Rz in laser cutting

Abstract

Laser cutting is one of the advanced machining methods for the material removing process. This paper explores the prediction model of the surface roughness (Ra) and roughness height (Rz) of laser beam cutting on acrylic sheets. The Box-Behnken design based Response Surface Method (RSM) was used to predict the effect of the laser cutting parameters, which are laser power, cutting speed and tip distance on Ra and Rz. The predictive models are in good agreement with the experimental results. The first order equation revealed that the power requirement was the dominant factor, followed by tip distance and cutting speed respectively. This observation indicates the potential of using RSM in predicting cutting parameters, thus eliminating the need for exhaustive cutting experiments to obtain the optimum cutting condition and enhance the surface roughness. © 2010 WIT Press.