In this paper the history of physically vapor deposited (PVD) coatings will be briefly reviewed. Golden colored TiN-coated high-speed steel tools suddenly became comercially available from various sources in the early 1980's. Competing deposition processes included ion plating, sputtering and arc evaporation. Subsequent work led to the development of first (Ti, Al)N coatings and then Ti(C,N) coatings. Inspite of some early predictions, neither one of these has yet totally replaced TiN. Intensive research has yelded many other coating alternatives. Some more recen examples include CrN, Ti2N, MoS2, superlattice nanolayered effort to synthesize new and better coatings, relatively little work been done to optimize the joint performance of both the cutting tool and the workpiece material. Recent results from dry turning tests show that considerable differences exist between various steels. It appears that calcium treatment if the workpiece material may increase the wear life if the cutting tools manifold provided that the tool or coating contains titanium. With the increasing interest in dry machining it can be expected that a proper coating and workpiece interaction will become increasingly important for achievement of good wear life.
