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

• TiSiC, Zr- and Cr-doped TiSiC coatings were prepared by cathodic arc method.
• Coatings were composed of FCC carbide solutions and amorphous carbon.
• Zr and Cr additions led to grain refinement and reduction in residual stress state.
• The Zr-doped coating exhibited high hardness (~ 42 GPa) and good adhesion (Lc = 36 N).
• Zr alloying improved the coating friction and wear performance of TiSiC coating.

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 (~ 0.3) and the lowest wear rate (~ 2 * 10− 6 mm3N− 1 m− 1).