Tribological behaviors of foamed copper/epoxy resin composites augmented by molybdenum disulfide and multi-walled carbon nanotubes

Abstract

A novel foamed copper/epoxy (FCE) composite possessing improved wear resistance was developed as a rubbing pair material. The composites consist of an open-cell foamed copper skeleton and an epoxy resin and auxiliary additives, such as molybdenum disulfide (MoS2) and multi-walled carbon nanotubes (MWCNTs). A universal UMT-2 friction and wear tester was utilized to study the tribological properties of the FCE composites under dry lubrication conditions. We found that the amount of MoS2, the porosity of the copper foam, and the presence of the MWCNTs all have an effect on the friction and wear properties of the composite materials. The friction coefficient of the composite material gradually decreases as the amount of MoS2 increases; however, the wear rate initially decreases and then increases. When the MoS2 content is 30%, the wear rate reaches a minimum. The wear rate decreases as the porosity of copper foam decreases, but porosity has little effect on the friction coefficient. As the rotation speed of the grinding steel plate and the applied load on samples increase, the wear becomes more significant. The presence of MWCNTs also increases the strength and wear resistance of the epoxy resin matrix. Depth-of-field microscopy and scanning electron microscopy were employed to observe the worn-surface morphologies and wear mechanism. The worn surface of the FCE composite matrix is divided into three parts: the hollow metallic copper skeleton region, the polymer zone, and the transition zone copper skeleton that contains some polymer material. It is important to note that the wear mechanism of the various compositions is adhesive wear and slight abrasive wear, and the fatigue crack that runs perpendicular to the direction of movement begins to form at higher speeds, which results in a higher wear rate.

The Influence of Copper Oxide Particle Size on the Properties of Epoxy Resin

“…The novelty of the field of copper-epoxy composites has been addressed in various studies. Xu et al [47] introduced a foamed copper-epoxy composite that showed improved wear resistance, making it a unique material for abrasion-resistance applications. Nur and colleagues [32] also observed flexural strength and modulus improvements by incorporating mixed copper particles into epoxy composites, highlighting the potential for innovative material improvements.…”

Surface wettability, tensile mechanical performance, and tribological behavior of polyimide/polytetrafluoroethylene blends enhanced with hydroxylated multiwalled carbon nanotubes at high relative humidity

“…Apart from the solid lubricants mentioned earlier, multiwalled carbon nanotubes (MWCNTs), as a typical one‐dimensional hollow nanostructured material, have drawn broad attention in polymeric composites and engineering technology fields due to their high thermal conductivity, fracture toughness, corrosion resistance, and intrinsic lubrication characteristics. [ 20–22 ] More importantly, MWCNTs can be chemically functionalized via many organic and inorganic modification reagents; therefore, many diverse chemical functional groups including carbonyl, carboxyl, hydroxyl, and amino groups have been grafted onto their surfaces. These characteristic functional groups provide numerous sites for MWCNTs to undergo reactions with polymeric composites and can be used to generate interfacial bonding forces between MWCNTs and polymeric matrices.…”

Exfoliated two-dimensional molybdenum disulfide reinforced epoxy syntactic foams

“…1 These interesting properties 3 has led to the exploration of MoS 2 , not only in the field of lubrication 4 but also in catalysis 5 and photovoltaics. 6,7…”

“…1 These interesting properties 3 has led to the exploration of MoS 2 , not only in the field of lubrication 4 but also in catalysis 5 and photovoltaics. 6,7 An interesting area, where the potential of MoS 2 remains largely unexplored is in marine and aerospace applications, where weight is a major constraint and lightweight materials with high specific strength are highly desirable. For such highperformance applications, hollow microballoon filled composites, more commonly known as 'syntactic foams' have been extensively studied.…”