Excellent tribological properties and unique wear-resistance mechanism of binderless tungsten carbide prepared via two-step oscillatory pressure sintering

Brittle fracture and damage have always been an unavoidable occurrence for ceramics, especially during the repeat friction process. In this work, two-step sintering was combined with oscillatory pressure sintering to fabricate binderless tungsten carbide with superior tribological properties, and the unique wear-resistance mechanism was investigated. The optimum friction coefficient and specific wear rate reached 0.49 and 2.17×10-7 mm3·N-1·m-1, respectively. Exceptional tribological properties were attributed to the superior comprehensive mechanical properties of ceramics and the structural height difference of the abrasion surface. The microstructure constructed by the ultra-homogenized grains had a high potential for resisting frictional wear, and the wear-resistant structure in-situ generated on the worn track that could effectively mitigate the adhesion effect during the friction process. The structural height difference, as a new category of wear-resistance structure, provided a new approach for alleviating the frictional wear phenomenon in ceramics.