Scratch response and tribological properties of TiAlSiN coatings deposited by reactive deep oscillation magnetron sputtering

TiAlSiN nanocomposite coatings were deposited using deep oscillation magnetron sputtering with various nitrogen flow ratio (f(N2)) of 0%?20%. The increase of f(N2) promotes phase separation from a single crystallographic TiAlSi to nc-(Ti,Al)N/a-Si3N4 phase. The introduce of N content leads to the formation of refined grain size, smooth morphologies and dense microstructure. Ti0.15Al0.39Si0.07N0.39 coatings with (Al;+;Si)/Ti ratio of 2.9 deposited at f(N2);=;10% reach the highest hardness of 32.8 GPa, H/E* of and 0.0837 and H-3/E*(2) of 0.23. The introduce of N leads to failure mode changing from brittle tensile cracking (through-thickness cracking) to buckle spallation (interfacial failure). Ti0.15Al0.39Si0.07N0.39 coatings with highest H, H/E* and H-3/E*(2) ratios show buckling failure with high L-C1 of 25.4 N and L-C3 of 43.6 N. Correspondingly, Ti0.15Al0.39Si0.07N0.39 coatings are subjected to oxidation wear with low coefficient of friction of 0.41 and specific wear rate of 0.39;;10(?6) mm(3) N-?1 m(?1).