Abstract
ZrTiN hard coatings were deposited on WC/TiC/Co cemented carbide substrate by multi arc ion plating. During the depositing, the four most important parameters are target current, nitrogen flowrate, deposition temperature and negative substrate bias voltage. This paper presented a detailed analysis of the effect of these four depositing parameters on the microstructures and properties of ZrTiN thin films respectively. In addition, we also systematically investigated the microstructure, elemental composition, crystal orientation, lattice parameter, grain size, adhesive strength and microhardness of the films. X-ray diffraction analysis indicated that only the face centred cubic phase was formed in the films, but the crystal orientation varied with different deposition conditions. Microhardness and adhesive strength of the coatings were associated with elemental composition, crystal orientation and microstructures. The optimum films obtained possessed comprehensive mechanical properties with an adhesive strength of 84·1 N and a microhardness of 30·4 GPa and exhibited the strongest (111) preferred orientation.
This work was supported by ‘the National Natural Science Foundation of China (grant no. 51075237)’, ‘the Taishan Scholar Program Foundation of Shandong’, ‘the Outstanding Young Scholar Science Foundation of Shandong (grant no. JQ200917)’ and ‘the National Basic Research Program of China (grant no. 2009CB724402)’.