PERFORMANCE BEHAVIOR OF PHYSICAL-VAPOR-DEPOSITION-COATED CERMETS IN INTERRUPTED-CUT MACHINING

This paper describes the performance behaviour of arc-physical vapour-deposition-coated cermets in interrupted-cut machining as a function of the coating substrate combination and the coating parameters. It also compares performance characteristics with those of coated carbides. One important result emerging from the study is that coated cermets achieve higher cutting speeds than those for coated carbides in interrupted cutting. It is also apparent that the toughness of the substrate grades, the tribological properties of the coating material and the process temperature of the coating process are all highly significant for the service properties of the cermet tools in interrupted-cut machining. Given suitable substrate qualities, tool lives can be increased significantly by physical vapour deposition coatings, especially by Ti-Zr-N coatings.