Multicomponent TiSiBC superhard and tough composite coatings by magnetron sputtering

Multicomponent TiSiBC thin film with high hardness and modulus of 45 GPa and 520 GPa with 50% elasticovery after unloading have been synthesised by single target magnetron sputtering. The thickness of the film was of the order of 4 μm. The film showed less than 0.1 value for coefficient of friction. The film showed amorphous matrix with crystalline nano phases of TiB2, phase containing Ti and Si and TiC, which led to achieve higher hardness, modulus with higher toughness. High values of hardness of these coatings were due to the high density of boundaries between the small, nanometer size grains embedded in the matrix of amorphous TiSiBC phases. The toughness value KIc measured by nanoindentation was found in the range of 4.5–5 MPa m1/2.