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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 Fe C bonds. Furthermore, the C Cr bond at the interface exhibits greater strength compared to the C W 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. • The WC-304 cemented carbide is prepared using the vacuum sintering process. • The binding work, interface energy, eletronic structure and interface bonding mechanism of WC-304 cemented cerbides are calculated. • When replacing Ni atoms in Fe structure, the interface spacing and the adhesion work have undergone a change. • The reason of the formation of stable interface is analyzed. [ABSTRACT FROM AUTHOR]

In-situ WC/Fe composites were prepared by spark plasma sintering, and the interfacial reaction of two phases was regulated by adjusting the atomic ratio of W-to-C. With the decrease of the atomic ratio of W-to-C, the content of Fe 3 W 3 C of the interfacial products of two phases decreased, and the hardness and wear resistance of WC/Fe composites increased. The phase composition of the composite remains relatively unchanged and the optimal wear performance is achieved when the atomic ratio of W-to-C is below 1:1.5. Meanwhile, based on the nanohardness results, the hardness distribution from WC to the substrate was determined. At a penetration depth of 300 nm, the interfacial fracture toughness of Fe 3 W 3 C was found to be 3.01 ± 0.82 MPa·m1/2. Additionally, the deformation rate of Fe 3 W 3 C was determined to be 89% based on the load-displacement curve. For the composites with W to C atomic mass ratio of 1:1.5, 1:1.76 and 1:2.02, oxidative wear may play an important role in reducing the specific wear rate, while for W to C atomic mass ratio of 1:1.3, micro-cutting wear may play a key role. Through a combination of simulation and experimentation, an analysis was conducted on the impact of the friction coefficient of composite materials on their wear resistance, as well as the stress situation of WC particles during the friction process. This analysis serves as a theoretical foundation for the results obtained in the testing process. • The interfacial reaction of WC/Fe composite was regulated by adjusting the atomic ratio of W-to-C. • The optimal wear performance is achieved when the atomic ratio of W-to-C is below 1:1.5. • Based on the nanohardness results, the interfacial fracture toughness of Fe 3 W 3 C was found to be 3.01 ± 0.82 MPa·m1/2. • The main wear mechanisms of each WC/Fe composite are different. [ABSTRACT FROM AUTHOR]