High Hardness and High Toughness WC–Fe–Ni‐Cemented Carbides Prepared by Hot Oscillating Pressing

Abstract

WC–Fe–Ni‐cemented carbides are prepared by hot oscillating pressing (HOP) and hot pressing (HP). Compared with the sample prepared by applying HP, the sample prepared by HOP shows higher density, lower carbide contiguity, more uniform distribution of binder phase, and finer WC grains. The average grain size of the HOP sample is 0.54 μm, where that of the HP sample is 0.67 μm. Moreover, the content of W in the binder phase is higher in the HOP sample than in the HP sample. The HOP sample exhibits a hardness of 2080 MPa and a fracture toughness of 15.95 MPa.m1/2, which are not only higher than those of the HP sample, but also higher than those of the WC–10Co alloys reported previously. The improvement in the mechanical properties is likely due to that the oscillatory pressure enhanced the flow of the liquid binder phase as well as influenced dissolution and re‐precipitation during densification process. Herein, it is indicated that HOP is an effective technique for the preparation of cemented carbides having high hardness and high toughness.