Synergy of B₄C@MoS₂ hybrid for significantly improved mechanical and tribological properties of PI/PTFE fabric composites

Abstract In this study, a hierarchical B₄C@MoS₂ hybrid is constructed by growing MoS₂ nanoflowers onto micro B₄C (boron carbide) surface via an in situ hydrothermal process. Thereinto, the PDA/PEI (polydopamine/polyethyleneimine) co‐deposition coating covers over the micro B₄C surface to serve as the interfacial interlayer responsible for assembling the B₄C and MoS₂ together strongly. The achieved B₄C@MoS₂ hybrid is used to strengthen the tribological performance of PI/PTFE fabric phenolic composites. Tests showed that the resultant B₄C@MoS₂/fabric composites exhibited effective enhancement in hardness because of the outstanding strength and modulus of B₄C. Meanwhile, the thermal stability of B₄C@MoS₂/fabric composites significantly outperformed the MoS₂/fabric composites resulting from the excellent thermal and barrier properties of B₄C. Moreover, the tribological tests manifested that the wear rate of B₄C@MoS₂/fabric composites was decreased by 84% compared to that of pure composites. The synergetic enhancement effect between B₄C and MoS₂ was revealed by worn surfaces and tribofilms analysis. The B₄C@MoS₂/fabric composites possessed the optimal wear resistance ascribed to the excellent load‐bearing capacity of B₄C and lubricating property of MoS₂.