COMPARISON OF ABRASION MODEL TEST-RESULTS AND MACHINING TESTS WITH PVD-COATED INDEXABLE INSERTS

The development of physical vapour deposition (PVD) coatings for impro ved wear resistance of cutting tools now is addressing more complex co ating systems. For example, this is verified by the fact that most of the commercial PVD coating companies now are offering ternary coating systems, such as TiAlN or Ti(C, N), in addition to the standard TiN. Q uaternary and quinternary systems are in development. While developing these new coating systems, more parameters have to be optimized which is resulting in larger series of experimental runs. Because it is imp ossible to consider all the coating variations in machining tests unde r real turning or milling conditions, it has to be proved how far mode l wear tests can help in preselecting the coatings with a good potenti al to perform successfully. The fact that model tests are able only to prove a single wear mechanism needs very careful verification. In thi s paper, we compare the results of turning or milling tests using TiN- , TiCN-, TiZrN-, ZrCN-and TiZrCN-coated tools with the results of abra sive wear tests. It is shown how far the model test result can give in formation about the potential of a coating in special cutting conditio ns, if the whole tribological system with the other affecting factors is to be evaluated.