Solid FeS lubricant: a possible alternative to MoS2 for Cu–Fe-based friction materials

Abstract

Molybdenum disulfide (MoS 2 ) is one of the most commonly used solid lubricants for Cu-Fe-based friction materials. Nevertheless, MoS 2 reacts with metal matrices to produce metal sulfides (e.g., FeS) and Mo during sintering, and the lubricity of the composite may be related to the generation of FeS. Herein, the use of FeS as an alternative to MoS 2 for producing Cu-Fe-based friction materials was investigated. According to the reaction principle of thermodynamics, two composites-one with MoS 2 (Fe-Cu-MoS 2 sample) and the other with FeS (FeS-Cu 2 S-Cu-Fe-Mo sample), were prepared and their friction behaviors and mechanical properties were compared. The results showed that MoS 2 reacted with the Cu-Fe matrix to produce FeS, metallic ternary sulfides, and Mo when sintered at 1050°C. The MoS 2 -Cu-Fe and FeS-Cu 2 S-Cu-Fe-Mo samples thereby exhibited similar characteristics with respect to phase composition, density, hardness, and tribological behaviors. Micrographs of the worn surfaces revealed that the stable friction regime for both composites stemmed from the iron sulfides friction layers rather than from the molybdenum sulfides layers.

Comparative study of different solid lubricants towards friction stability in a non-asbestos disc brake pad

“…NAMO exhibited moderately poor resistance than others. The solid polarizing effect on the sulfur atom is shown by the small electropositive molybdenum present in the MoS 2 lattice layer (Peng et al , 2017). These electropositive poles result in excellent adhesive properties with the metal substrates.…”

MoS2/PDA@Cu composite as a peroxidase-mimicking enzyme with high-effect antibacterial and anticancer activity

“…† This phenomenon accounted for the corrosion effect of MoS 2 , which is not conducive to the growth of Cu Nps. 50 In contrast with MoS 2 , PDA could provide the growth sites for Cu Nps and prevent the surface corrosion of MoS 2 . The Bragg diffraction pattern of Cu Nps was obtained by Fourier transform using the software Digital Micrograph, as shown in Fig.…”

Tribological performance of maintenance-free Cu-Sn-Ni-MoS2 composites over a wide temperature range

“…Above all, the solid solution strengthening matrix materials can be formed through adding alloying elements such as Zn Ni, Sn and Fe; meanwhile, the mechanical properties of matrix materials can be improved by surface plating (Varol and Canakci, 2015; Senthil Kumar et al , 2013; Zou et al , 2018; Radhika et al , 2018; Zhang et al , 2016). It is effective to improve the interface adhesion, mechanical properties and tribological properties by adding MoS 2 into Cu-Fe, Cu-Sn alloy or copper-plated alloy (Varol and Canakci, 2015; Peng et al , 2017; Fu and Wang, 2010). It was found that the high-temperature tribological properties of the composites can be improved by the addition of an appropriate amount of MoS 2 at high temperatures.…”