The effect of deposition temperature on microstructure and properties of thermal CVD TiN coatings

Coatings of TiN have been deposited by thermal CVD between 850 and 1050 degrees C and characterized with respect to their microstructure as well as mechanical and tribological properties. X-ray diffraction (XRD) analysis yields the formation of textured films, particularly at low deposition temperatures. It is shown that the coating hardness changes with the texture, where highly (2 11) oriented films exhibit a lower hardness compared to non-textured coatings. The wear resistance has been determined by dry sliding experiments against Al2O3 balls at 25 degrees C on both as-deposited and polished samples. Independent on the surface roughness, the smaller grain size of the textured films causes a higher toughness and results in a better wear resistance. (C) 2007 Elsevier Ltd. All rights reserved.