Comparison of Tribological Performance of Polyoxymethylene/Graphite Composite and Pure Polyoxymethylene Polymer

Abstract

The friction and wear characteristics of engineered thermoplastics, namely unfilled polyoxymethylene (POM) and 10% graphite-filled polyoxymethylene (POM+10%Gr), sliding on steel under dry conditions were investigated using a pin-on-disc tribometer. The influence of applied load and sliding speed on the tribological properties of POM and POM+10%Gr on a steel counterface under dry sliding conditions was examined. Experimental results showed that the coefficient of friction (COF) of the POM and POM+10%Gr polymers decreased with increasing applied load. In addition, the wear rate (WR) values of the POM and POM+10%Gr polymers decreased with the increase in applied load. However, for all polymers, the specific wear rate values exhibited an increase with the rise in sliding speed. The best polymer material is found which is POM+10%Gr with respect to friction and wear behavior in this study. The worn surfaces of the engineering thermoplastics were investigated by optical microscope. Optical micrographs indicated that adhesive wear was the predominant wear process under dry sliding circumstances.

Keywords

• Friction
• Graphite
• POM
• Tribology
• Wear

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