Synthesis of titanium carbide/chromium carbide multilayers by the co-evaporation of multiple ingots by electron beam physical vapor deposition

Titanium carbide and chromium carbide multilayer coatings with varying individual layer thicknesses were synthesized by the co-evaporation of titanium, chromium, and carbon (through tungsten) ingots by electron beam-physical vapor deposition. The adhesion of the multilayer coatings was found to be greater than 50 N. The hardness of the titanium carbide/chromium carbide multilayer coatings was found to increase from 1302 VHN_0.050 to 2052 VHN_0.050 by decreasing the thickness of the individual layer from 1.2 to 0.1 μm. In addition, the average grain diameter was also found to decrease from 3.315 to 0.356 μm by decreasing the thickness of the individual layers. The fracture toughness of the TiC/CrC multilayer coatings decreased from 4.179 to 1.411 MPa-m with decreasing layer thickness. Lastly, the amount of compressive stress in both the TiC and CrC layers within the multilayer coating was found to decrease with decreasing individual layer thickness. The samples were characterized by various techniques including Vicker's hardness, X-ray diffraction, scanning electron microscopy, scratch testing and fracture toughness, with the results being presented.