Research on the tribological performance of Cr₂O₃ filled with bronze‐based PTFE composites

Abstract

Enhancement of the wear resistance of bronze-filled polytetrafluoroethylene (PTFE) composites has been achieved using various fillers, for example, chromic oxide (Cr 2 O 3 ), molybdenum disulfide (MoS 2 ), graphite, and nanometer aluminum oxide (nAl 2 O 3 ), in the present study. The wear resistance was evaluated by a block-on-ring wear tester, and the effects of fillers on the wear resistance as well as the mechanism were investigated. The wear rate for the composite where the recipe containing 59% PTFE 1 40% bronze 1 1% Cr 2 O 3 was 0.5 3 10 25 mm 23/N m and for the composite in the recipe containing 60% PTFE 1 40% bronze was 4.2 3 10 25 mm 23 /N m, which meant that that Cr 2 O 3 increased the wear resistance by approximately 10 times. The differential scanning calorimetry measure analysis showed that Cr 2 O 3 had a positive effect on the crystallization of PTFE; the crystallinity of PTFE composites increased from 45% to 52%, which exhibited improved wear resistance. Wear testing and scanning electron microscope analysis had shown that Cr 2 O 3 had a positive effect on the formation of transfer film and keeping it stable to exhibit improved wear resistance. X-ray photoelectron spectroscopy results also showed that Cr 2 O 3 was effective in tribochemical reactions during sliding against stainless ring; these maybe responsible for forming transfer film and lowering wear rate of composite.

Enhanced tribological properties of bismaleimides filled with aligned graphene nanosheets coated with Fe3O4 nanorods

“…6a), it can be seen that plastic deformation and ploughing predominantly constitute the worn surface; there is also some debris on the worn surface, which is characteristic of the adhesive wear mechanism and indicates that the wear resistance of BMI is poor when sliding against the steel ring. 41 However, for the aligned GNS-Fe 3 O 4 /BMI composites (Fig. 6b), the wearing of the surface is much milder, which is characteristic of the abrasive wear mechanism.…”

The Effect of Grafting Density on the Crystallization Behaviors of Polymer Chains Grafted onto One-Dimensional Nanorod

“…It was previously reported that physical properties of composite materials, such as modulus, tensile strength and conductivity, can be dramatically improved by adding fillers into polymers [1][2][3][4][5][6][7]. Aluminium oxide, carbon nanotubes, silica particles, and graphene are the commonly used nanoscale fillers, which can significantly change crystalline morphologies of polymer nanocomposites, thus further leading to the improvements in mechanical properties [8][9][10][11][12][13][14]. It should be noted that the interaction between polymers and fillers is important for the crystallization of polymer nanocomposites [15,16].…”

The Tribological and Sealing Properties of PFA Composites

“…To solve high wear rate, various suitable fillers have been added to PTFE to improve the wear resistance. Most serve to moderately reduce wear (by one or two orders of magnitude) while increasing friction [1][2][3][4]. However, complex geometries of PTFE products must be machined after the part has been sintered, which adds cost to the manufacturing process.…”