Abstract
TiAlN/SiN x multilayers were fabricated by RF reactive magnetron sputtering. Characterizations by TEM, dark-field images, and SEM revealed the dependence for the thickness of SiN x (l SiNx ) on the texture and microstructure evolution in multilayers. Epitaxial stabilization in multilayer ameliorated the hardness and H/E ratio. With increasing the l SiNx , the amorphous SiN x altered the coherent interfaces and the superlattice structure, leading to an appreciable decrease in hardness. Nevertheless, this fine-grained coating exhibited superior resistance to plastic deformation. In the ball-on-disk wear tests, the observation of coefficient of friction, worn surfaces, and cross-sectional worn scars verified that multilayers showed better tribological resistance than that of TiAlN monolayer. Two antiwear mechanisms on the basis of hardness variation and microstructure evolution were proposed to elucidate the favorable durability of TiAlN/SiN x multilayers with various l SiNx . © 2013 The American Ceramic Society.