On the feasibility of using cryo-treatment as a tool to enhance the abrasive wear behaviour of solid-lubricated polymeric composites

Abstract

Cryo-treatment, a bulk modification technique, is fast emerging as a way with which to improve the wear resistance of metals. This technique has also shown the ability to enhance significantly the abrasive wear performance of some polymers and their short glass-fibre reinforced composites. In this work, short carbon-fibre reinforced composites of some heat resistant polymers, such as polyetherimide, polyethersulphone, polyamide 6,6, polyetheretherketone, and polytetrafluoroethylene, were selected to explore the potential of cryo-treatment. The selected materials were cryogenically treated by cooling them to the temperature of liquid nitrogen. The abrasive wear tests were carried out at ambient temperature in single pass conditions at various loads, on a pin-on-disc machine, using silicon carbide paper as a counterface. The investigations revealed that this technique has definite potential to increase the wear performance of carbon-fibre reinforced composites. An increase in hardness due to cryo-treatment was thought to be responsible for an observed improvement in wear performance. However, the extent of improvement in the wear performance was not matched by an increase in the hardness value. Scanning electron microscopy proved useful in examining the morphological changes in the composites due to cryo-treatment.