Effect of re-melting temperature on interface and compression fracture mechanism of WC_P/Fe composites

In order to investigate the effects of re-melting temperature on the interface characteristics and mechanical properties of WC_P/Fe composites, the WC_P/Fe composites were prepared by powder sintering and the interface of the composites were re-melted at the different temperatures. The research provides a theoretical basis for the interface structure design and the application of particle reinforced metal matrix composites. The results show that a phase transition reaction occurs from WC to W₂C with the increase of the re-melting temperature, and W₂C reacts with Fe to generate the solid Fe₃W₃C phase. Besides, the width of interface reaction zone increases with the increase of the re-melting temperature. The interfacial morphology is transformed from discontinuous cycle to a continuous cycle and then to serration shape. The compressive strength of the WC_P/Fe composites exhibits the trend of increasing and then decreasing. When re-melting temperature is 1 300℃, the interface width is 13.5 μm and the interface reaction zone appears in continuous cycle shape. The internal compressive cracks of the composites are not inclined to initiate and propagation. Meanwhile, the compression strength of composites is 386 MPa when it reaches the maximum.