Enhanced compressive strength by Ti-Cr coating on cBN particle surface using vacuum vapor deposition

In order to enhance compressive strength of the coating on cBN particles, this study proposes using vacuum vapor deposition to achieve a Titanium-Chromium (Ti-Cr) co-deposited coating on the surface of cBN particles. Base on deposition process of the Ti-Cr coating using vacuum vapor deposition technology, it proposed a simulation model by an Angular Coefficient Method (ACM), and conducts compressive strength experiments on the Ti-Cr coating of cBN particles. Using the simulation and analysis model, the effect of temperature on the formation of Ti-Cr coating during the reaction process was systematically analyzed, the molecular flow, the change of film thickness, and the deposition rate at different temperature stages was got, and verify the simulation results through experiments. The formation mechanism of Ti-Cr co-deposited coatings was derived by SEM, XRD characterization and reaction thermodynamic analysis. Experiments show that Ti-Cr co-deposited coatings are effective in increasing compressive strength, and the experimental results can be a guidance in controlling Ti/Cr amount in the coatings. In addition, it was found in experiments that by using vacuum vapor deposition technique, Ti/Cr powder mixing ratio of 1:1 provided the best compressive strength, and the compressive strength increased with higher Cr content in the coating after heating. This achievement is of significant importance for the formation of alloyed coatings on superhard materials, enhancing the wettability between the surfaces of superhard materials and their substrates under high-temperature conditions.