Ultrafine‐grained WC‐based ceramics prepared via two‐step oscillatory pressure sintering

Abstract

Grain growth in ceramic‐based composites during sintering has always been an unavoidable problem. Based on the theory of fine‐grained reinforcement, the concept of rapid densification was coupled with the inhibition of grain growth to fabricate ultrafine‐grained WC‐based ceramics. Herein, by combining two‐step sintering with oscillatory pressure sintering (OPS), a new sintering process—two‐step oscillatory pressure sintering (TSOPS), was used for the preparation of ultrafine‐grained WC‐based ceramics. The comparison of the OPS with the TSOPS validated the feasibility of the strategy in achieving homogeneous and fine‐grained microstructures. The optimum mechanical properties of Vickers hardness, fracture toughness, and flexural strength reached up to 29.56 GPa, 7.97 MPa m1/2 and 1591 MPa, respectively. A developed TSOPS process was proposed and proved to dominate the grain size distribution homogenizing, which contributed to the simultaneous enhancement of mechanical properties of the ceramics.