Effect of W-to-C atomic ratio on microstructure and performance of in-situ WC/Fe composite prepared by spark plasma sintering

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 Fe3W3C 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 Fe3W3C was found to be 3.01 +/- 0.82 MPa & sdot;m1/2. Additionally, the deformation rate of Fe3W3C 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.