Microhybrids of metal powder incorporated in polymeric matrices: Friction, mechanical behavior, and microstructure

Abstract

The polymers used as a matrix were low density polyethylene (LDPE) and a thermoplastic elastomer (TPE). The metal particles were Al, Ag, and Ni with micrometer diameters. The metal concentration varied from 0 to 10 wt%. Dynamic and static frictions on tetrafluoropolyethylene and stainless steel as sliding surfaces were determined and tensile tests were performed. Secondary electron and backscattered electron SEM images were taken to determine microstructures of the hybrids. Addition of metal powder to the matrix results in reduction to a minimum of the tensile elastic modulus for low metal concentrations, and increase in the modulus with further addition of metal particles. For the TPE, the tensile modulus exceeds that of the pure material. Small metal particles increase the modulus at lower concentrations than larger ones. Hardness varies with the filler concentration, similarly as tensile modulus does. Backscattered electron SEM images show uniform dispersion of the metal particles at the surfaces and in the bulk. The contrast is enhanced by large differences in atomic numbers between the fillers and the matrices. Ni microparticles in LDPE cause crack arrest seen in SEM. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers

Surface and electrical properties of high density polyethylene + carbon black composites near the percolation threshold

“…Above the threshold, the friction begins to increase. We have seen a similar behavior in polymer + metal particles hybrids [28]. There is a minimum value of friction around the percolation concentration that represents a reduction of 43 % and 57 % for 1.0 N and 20.0 N, respectively.…”

Effect of particle size on the properties of highly-filled polymers for fused filament fabrication

“…A decrease in viscosity has also been reported in the literature when using coarser particles in PIM feedstocks [4]. Additionally, it has been reported in the literature of polymer-metal composites filled with particles that increasing the particle size decreases the modulus [5] and elongation at break [6] of the composite materials. Therefore all our results are in agreement with the literature.…”

“…This includes the material properties and the geometrical shape of the filament. In this paper, we investigated one important factor that affects the material properties strongly of highly filled systems: particle size distribution (PSD) of the filler powders [4,5]. In short, this paper presents the effect of PSD on the modulus, elongation at break and apparent viscosity of highlyfilled filaments with 316L stainless steel.…”

Wear and Friction Characteristics of TiO2 – ZnO / PMMA Nanocomposites

“…Since tribological ponders incorporate the coordinated effort between surfaces, it is imperative to reveal whether the metal particles are accessible on the composite surface. In various past works it can be exhibited that metallic particles can be found on the surface of the composite and are all around scattered, aside from metallic particles (scaled down scale and nano measure) which tend to shape agglomerates as far reaching as a couple of microns in separation crosswise over [22]. In general, the wear mechanisms of materials include adhesion, abrasion, fatigue, impact, electrical and chemical wear.…”