Investigation of nanostructured TiSiC-Zr and TiSiC-Cr hard coatings for industrial applications

TiSiC, TiSiC-Zr and TiSiC-Cr coatings, with Zr and Cr added to TiSiC base coating system, have been prepared by cathodic arc method in a CH4 reactive atmosphere. All the coatings exhibited nanocomposite structures, mainly consisting of a mixture of crystalline face-centered cubic (FCC) carbide solid solutions, with a preferential (220) texture, and amorphous carbon phases. The coatings showed compact, homogeneous and featureless cross-sectional microstructures. Cr and Zr incorporation in TiSiC resulted in lattice distortion (from a lattice parameter of 0.4358 nm for TiSiC, to 0.4536 nm and 0.4320 nm for TiSiC-Zr and TiSiC-Cr, respectively) and grain refinement. Also, alloying TiSiC led to a reduction of stress in the films, from -3.12 GPa (TiSiC) to -2.37 GPa (TiSiC-Cr) and -2.58 GPa (TiSiC-Zr), and to film hardness changes (TiSiC: 35.2 GPa; TiSiC-Zr: 42.1 GPa; TiSiC-Cr: 31.4 GPa). Of the investigated coatings, TiSiC-Zr exhibited the lower dry friction coefficient (similar to 0.3) and the lowest wear rate (similar to 2 (*) 10(-6) mm(3)N(-1) m(-1)). (C) 2014 Elsevier B.V. All rights reserved.