First principles calculation of interfacial stability, electronic and mechanical properties of WC-304 cemented carbides

Abstract

Based on first-principles Density functional theory (DFT), the binding work, interface energy, electronic structure and interface bonding mechanism of WC-304 stainless steel with Fe-Cr-Ni cemented carbides were calculated. The results show that the interface between Fe (100) and WC (100) C-teminations has the lowest interface distance and the highest binding work when it is constructed with MT position. The subsitution of Fe atoms with Ni atoms results in a decrease in the interfacial distance, measured at 0.9412 Å, accompanied by a simultaneous increase the adhesion work to 9.3647 J/m2. The stability of the interface structure is significantly influenced by the bonding strength of FeC bonds. Furthermore, the CCr bond at the interface exhibits greater strength compared to the CW bond when the W atom is replaced by Cr atom. Therefore, the doping of Cr and Ni atoms in 304 stainless steel results in a more stable interface structure between WC and Fe. The results have important guiding significance for improving the interfacial strength and stability of WC-Fe cemented carbide.