Improvement of the tribological behavior of TiN/CrN multilayer coatings by modulation wavelength variation

Abstract

Hard coatings are widely used in materials engineering as surface coatings to protect mechanical parts subject to friction. For a coating to be functionally successful, it should possess high wear resistance. Experimental work has been performed on TiN/CrN multilayer coatings with various modulated periods, deposited on XC48 steel substrates having two different surface roughnesses using reactive direct current magnetron sputtering. Their Tribological performances were investigated following dry sliding wear tests using a tribometer with ball-on-flat contact configuration. The prevailing wear mechanisms of TiN/CrN coatings are dominated by oxidation of wear debris and counter material transfer. The decreased wear rate was significantly influenced by both the reduction of the period thicknesses and the increase of substrate surface roughness. Nonetheless, varying thickness period in the multilayer and increasing the substrate roughness did not show any significant wear resistance improvement.