FRICTION AND WEAR OF SCRATCHED POLYMERIC COMPOSITES

The present study investigates friction and wear of polymeric composites by scratch test. Polymeric composites consisting of polymethyl methacrylate (PMMA) and polyethylene (PE) have been filled by sand, aluminum, copper, carbon fibers and carbon nanotubes. The tribological properties have been determined by scratch test. The experiments revealed that friction coefficient slightly increased up to maximum then decreased with increasing the applied load. Filling composites by sand increased friction coefficient and decreased wear, while copper and aluminum as fillers did not alter frictional behavior but they increased wear. It was observed that addition of carbon fibers and carbon nanotubes drastically decreased friction coefficient and wear. It seems that they provided low shear layer in the in the contact surface of the tested composites that decreased friction. Besides, their lubricating action decreased wear.