Influence of Deposition Temperature on Microstructure and Mechanical Properties of TiAlN Coatings for High Performance Manufacture

Abstract:

TiAlN coatings were deposited at various deposition temperatures using vacuum arc ion plating (AIP) for the high performance manufacture. The relationships between deposition temperatures and surface properties were investigated. Results show that surface macroparticles (MPs) decrease in number and size with increasing the deposition temperature because of ion bombardment. When deposition temperature increases, the grain size on the top coating first decreases sharply, and then increases gradually. Furthermore, deposition temperature has little influence on the phase constituents and chemical compositions of the resultant coatings. With raising the deposition temperature, the hardness and adhesion strength first increase rapidly, and then decrease gradually. The deposited TiAlN coating exhibits the highest hardness and the strongest adhesion strength when deposition temperature is set at around 450 °C. The mechanism of the above phenomena is attributed to the variations of microstructure and residual stress between the surface and interface during the deposition process. The resultant coatings have a good thermal stability in air at temperatures up to 900 °C.