Super wear-resistant WB₄–B super-hard ceramic by in-situ formed lubrication film in high moisture

Only a few materials demonstrate ultralow wear performance in specific fragile environments. We propose a self-adaptive wear strategy to achieve excellent wear resistance at high moisture contents through a super-hard substrate and an in situ lubrication layer. We prepare “self-adaptive” super wear-resistant WB₄–B ceramic with a wear rate of 1×10⁻⁷ mm³·N⁻¹·m⁻¹ in dry environments, which relies on the superhardness of WB₄ and B dual phases to maintain microstructural stability. The wear rate decreases further to 1×10⁻⁸ mm³·N⁻¹·m⁻¹, accompanied by a low friction coefficient of approximately 0.1, due to the in situ H₃BO₃/WO₃ lubrication film in the moist environment. In addition, this excellent wear resistance performance remains stable under a high contact stress of 2.81 GPa and long friction cycles of 1×10⁵. The excellent wear resistance of WB₄–B ceramic, as well as their excellent adaptability under harsh conditions, improves component performance and reliability in environments that are often considered challenging for traditional materials.