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SiC whisker (SiCw)‐reinforced SiC composites were prepared by an oscillatory pressure sintering (OPS) process, and the effects of SiCw content on the microstructure and mechanical and tribological properties of such composites were investigated. The addition of SiCw could promote the formation of long columnar α‐SiC, and the aspect ratio of α‐SiC grains first increased and then decreased with the increase of SiCw content. When the SiCw content was 5.42 wt%, the relative density of the SiC–SiCw composite reached up to 99.45%. The SiC–5.42 wt% SiCw composite possessed the highest Vickers hardness, fracture toughness, and flexural strength of 30.68 GPa, 6.66 MPa·m1/2, and 733 MPa, respectively. In addition, the SiC–5.42 wt% SiCw composite exhibited the excellent wear resistance when rubbed with GCr15 steel balls, with a friction coefficient of .76 and a wear rate of 4.12 × 10−7 mm3·N−1·m−1. This could be ascribed to the improved mechanical properties of SiC–SiCw composites, which enhanced the ability to resist peeling and micro‐cutting, thereby enhancing the tribological properties of the composites.

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It remains as a challenge to develop binderless WC ceramics that integrate high mechanical properties and low friction wear. Here, we report the preparation of strong and tough WC ceramics with low wear rate by adding graphene nanoplatelets (GNPs) and using oscillatory pressure sintering (OPS) process. The introduced GNPs lead to the formation of nearly fully dense composites with the aid of an oscillatory pressure. The OPS‐prepared WC–0.3‐wt% GNPs composites reached a high flexural strength, hardness, and fracture toughness, being up to 1420 MPa, 24.9 GPa, and 6.89 MPa m1/2, respectively. Moreover, a low friction wear rate of 3.17 × 10−7 mm3 N−1 m−1 is achieved for such composites, which can be ascribed to the formation of a friction lubrication film during dry sliding friction process and their higher mechanical properties.

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