Controllable in-situ synthesis of MoS2/C in plasma-sprayed YSZ coatings: Microstructure, mechanical and tribological properties

Plasma-sprayed ceramic self-lubricating coatings are limited in their practical applications due to the degradation of mechanical properties caused by tribological design. Herein, a robust self-lubricating ceramic coating was fabricated by combining in situ synthesis of molybdenum disulfide/carbon (MoS2/C) with the plasma spray technology process. Results show that MoS2/C grows in situ in the pores and micmcracks of plasma-sprayed yttria-stabilized zirconia (YSZ) coatings. Through the addition of MoS2/C, the hardness and cohesive strength of the coating could be significantly improved. Furthermore, the composite coating with the highest MoS2/C content exhibits the best tribological properties: the coefficient of friction is reduced by 79.6 % to 0.16, and the specific wear rate drops from 1.36 x 10(-3) to 6.27 x 10(-7) mm 3 N-1.m(-1). The improved tribological performance is attributed to a well-covered lubricating film composed of C, MoS2, YSZ, and Al2O3 . The proposed strategy eliminates the most significant pain points of mechanical properties degradation of traditional ceramic self-lubricating coatings caused by tribological design and is believed to have great potential applications in wide engineering sectors.

Automated summary

A self-lubricating ceramic coating with improved tribological properties was successfully fabricated by combining in situ synthesis of MoS2/C with plasma spray technology. The coating showed enhanced hardness and cohesive strength and exhibited lower friction coefficient and wear rate. This new strategy addresses the mechanical properties degradation issue of traditional ceramic self-lubricating coatings caused by tribological design.