In this study, the influence of micro-and nano-filler content on the mechanical properties of epoxy composites was studied. The matrix material is epoxy; the micro-fillers are Al 2 O 3 , TiO 2 and fly ash added in 10 wt% to 30 wt% by weight ratio; the nano-fillers are Al 2 O 3 , TiO 2 and clay added in 2.5 wt% to 10 wt% by weight ratio. Test samples were prepared using an open mould type die. Tensile, three-point bending and hardness tests were carried out. The tensile strength, elastic modulus, elongation at break, flexural strength, flexural modulus, and the hardness of the composite materials were obtained and evaluated. The results show that the tensile strength, flexural strength and elongation at the break values of composites decreased while the tensile modulus and flexural modulus increased with the increasing micro-and nano-filler content ratio.

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In this study, the influences of wax content on the tribological and mechanical performance of nylon-polytetrafluoroethylene blend were evaluated. Wear tests were carried out using nylon 6 + 10% polytetrafluoroethylene + wax pins on AISI 316 L disc material. The wax percentages in the blend are 2%, 4% and 6% by weight. Tests were carried out at room temperature with applied loads of 50–100 N and sliding speeds of 0.4–1.6 m/s. These conditions are equvilent to a combined pressure and speed factor values of 0.141–5.664 MPa m/s. Although the results showed a slight drop in mechanical properties, the friction coefficients and the wear rates of nylon blend were significantly reduced by the addition of wax filler. The friction coefficient was reduced from 0.29 to 0.13 and the reduction in the wear rate was up to 73%. Furthermore, the results also showed that the change in pressure and speed factor values did not have a significant influence on the specific wear rate values. Finally, micrographs of the the worn surfaces showed the presence of transfer film, deformation and adhesive wear mechanisms.

In this study, the influence of micro- and nanofiller contents on the tribological performance of epoxy composites was studied. The fillers are micro-Al2O3, micro-TiO2, and micro-fly ash and nano-Al2O3, nano-TiO2, and nanoclay fillers. The microfillers were added to the epoxy by 10%, 20%, and 30% by weight. The nanofillers were added to the epoxy by 2.5%, 5%, and 10%. Friction and wear tests were conducted using the pin-on-disc arrangement. Tribo elements consisted of polymer pin and DIN 1.2344 steel counterface disc. A load value of 15 N, a sliding speed of 0.4 m/s, a sliding distance of 2000 m, and dry atmospheric conditions were applied to test conditions. The results show that the friction coefficients and the specific wear rates of the nanofilled composites increase as the filler content increases. For microfiller-filled epoxy composites, these values decrease as filler content increases. The tribological performance of epoxy composites is enhanced by the addition of microfillers, and the higher enhancement is reached with the addition of 30% fly ash filler. Finally, the pin and disc worn surface images show the presence of adhesive and some abrasive wear mechanisms.

The friction and wear performance of cast polyamide, unfilled poly-oxy-methylene, 10 wt.% graphite filled polyamide 6, 10 wt.% graphite filled poly-oxy-methylene, and 10 wt.% graphite plus 6% wax filled polyamide 6 sliding against stainless steel under dry sliding conditions were studied. The aim was to evaluate the tribological behavior of the above materials which enables suggesting alternative material for costly cast polyamide polymer in industrial applications. Tribological tests were carried out using a pin-on-disk arrangement at a sliding speed of 0.5–2.0 m s−1 and under applied loads of 50 to 150 N. The results showed that the friction coefficient of the tested materials decreases with the increase in applied load as well as with the decrease in sliding speed values. Furthermore, the lowest wear rate is 2.24−15 m2 N−1 for 10 wt.% graphite filled polyamide 6 composite. This suggests its use instead of cast polyamide polymer. Finally, it is concluded that the wear mechanism includes transfer film and deformation.