Tool selection based on surface roughness in dry facing repair operations of magnesium pieces

This paper presents an experimental study on the dry facing of pieces of UNS M11917 magnesium. The work was focused on repair operations that are typically carried out with low-performance cutting conditions. The main goal of this study was to determine the tool that best suits the requirements of surface roughness for these operations. The tools considered had the same geometry but different coatings and were selected from among the most commonly used tools for magnesium and the hybrid structures formed by magnesium and other materials. The effects of spindle speed and feed rate were also considered to determine which factors and their possible interactions are more crucial. The tests were conducted following the Taguchi orthogonal design of experiments (DOE), and the results were analysed by the analysis of variance (ANOVA) method. A model for estimating the expected surface roughness in terms of the average roughness, Ra, was also developed.