Cobalt concentration on the interface mechanism between diamond coating and cemented carbide substrate by first-principles calculation and experimental study

In this paper, cobalt concentration on the interface mechanism between diamond coating and cemented carbide substrate was used by first-principles calculation and experimental study. The interface model was built and analyzed. The effect of pretreatment time on the Co concentration on the surface of cemented carbide was studied. The relationship between the bond strength of the WC–Co/diamond interface was analyzed based on energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), Raman spectroscopy and indentation. The simulation results showed that the bonding strength of the WC–Co/diamond interface increased gradually with the decrease of Co concentration and has an extreme value. The test results showed that the pretreatment decobaltization time was 20 min and the bonding strength of the membrane substrate is good. What was more, the results of EDX, SEM, Raman, indentation confirmed this conclusion.