Facing SiCp/Mg metal matrix composites with carbide tools

TiCN/TiN coated carbide cutting tools were used to study the finish machining characteristics of a silicon carbide particle reinforced magnesium metal matrix composite (SiCp/Mg MMC). A fully replicated two-level 2(4) full factorial with centerpoints was conducted while facing the MMC with process variables including feed, cutting speed, depth of cut and side cutting edge angle; and response variables of cutting forces, chip formation, surface roughness and tool wear. Results showed both continuous and semi-continuous chips were formed with the machining conditions used in this study. Abrasive wear of the flank face was observed to be the dominant tool-wear mechanism for all conditions within this study. It was observed that a greater depth of cut reduced the amount of tool wear for a given volume of material removed. Surface roughness values were within the range of 0.2-3.0 mu m. (c) 2005 Elsevier B.V. All rights reserved.