ABSTRACT
Electric static charges generated from friction of engineering materials have a negative effect in technological applications. The increased use of polymeric materials raised the importance of studying that effect. The present study investigates the voltage generated from the dry sliding of aluminium oxide (Al2 O3), copper (Cu), aluminium (Al), iron (Fe), silicon oxide (Si O2), polymethyl methacrylate (PMMA), high density polyethylene (HDPE) and low density polyethylene (LDPE) against synthetic rubber, HDPE, polypropylene (PP) and polytetrafluoroethylene (PTFE).
It was found that voltage generated from the sliding of aluminium oxide, copper, aluminium, iron and silicon oxide against rubber generated the lowest voltage, while PTFE showed the highest one. Generally, voltage decreased with increasing load due to heating process which increased the temperature of the friction surfaces and consequently the relaxation of the electric charge proceeded. Besides, it was observed that the maximum level of the voltage generated from the materials is dependent on their position in the triboelectric series relative to the counterface. The triboelectric series can be used to determine the charge polarity of the materials. This series can be used to evaluate the relative charging capacity of many polymeric materials.