Study of the performance of PVD and PCVD coated cermets for different cutting applications

The performance of PVD and PCVD coated cermets has been investigated for turning and milling applications. Two different cermet materials were used to have both harder and tougher substrates. The coatings used for the cutting tests were: TiN (PVD). (Ti,Al)N (PVD), TiN (PCVD) and a multilayer TiN/A sub 2 O sub 3 /TiN (PCVD). The coated cermets have been compared with uncoated cermets and, for some applications, with hardmetals. A great variety of workpiece materials (41CrS4, C45W and 42CrMo4 steels, DTD5212 Ti alloy, GDAlSi8Cu Al alloy and GGG 40 cast iron) have been used to evaluate the performance of the cermets. After the cutting tests wear analysis has been performed with electron microscope. For the cermet materials used the cutting conditions were very important to achieve an improvement with cermet inserts compared to hardmetals. Furthermore a clear improvement could be seen with coated cermets compared to uncoated cermets.