摘要
The wide use of epoxy composites as bearing materials in electronic appliances necessitates studying their frictional behaviour under the influence of magnetic field. Experiments were carried out to investigate the effect of magnetic field on the friction coefficient displayed by the scratch of epoxy composites filled by iron, copper and aluminium particles at different concentrations. It was observed that, for epoxy filled by the metallic fillers (iron, copper and aluminium), under the effect of the magnetic field, friction coefficient showed relative decrease then significantly increased with further increase of the intensity of the magnetic field. Besides, friction coefficient increased with increasing the content of the metallic fillers due to the decrease of the strength of the epoxy matrix. The values of friction coefficient displayed by epoxy filled by copper were lower than those observed for epoxy filled by iron. Filling epoxy by aluminium displayed lower friction coefficient than that observed for epoxy composites filled by iron and copper. This can be attributed to the charging of aluminium by positive charge when slid against steel. The resultant charge on the sliding surfaces was lower than that generated when epoxy was filled by iron and copper. In that condition, the adhesion of epoxy composites would be relatively weaker leading to the decrease of friction coefficient.
The wide use of epoxy composites as bearing materials in electronic appliances necessitates studying their frictional behaviour under the influence of magnetic field. Experiments were carried out to investigate the effect of magnetic field on the friction coefficient displayed by the scratch of epoxy composites filled by iron, copper and aluminium particles at different concentrations. It was observed that, for epoxy filled by the metallic fillers (iron, copper and aluminium), under the effect of the magnetic field, friction coefficient showed relative decrease then significantly increased with further increase of the intensity of the magnetic field. Besides, friction coefficient increased with increasing the content of the metallic fillers due to the decrease of the strength of the epoxy matrix. The values of friction coefficient displayed by epoxy filled by copper were lower than those observed for epoxy filled by iron. Filling epoxy by aluminium displayed lower friction coefficient than that observed for epoxy composites filled by iron and copper. This can be attributed to the charging of aluminium by positive charge when slid against steel. The resultant charge on the sliding surfaces was lower than that generated when epoxy was filled by iron and copper. In that condition, the adhesion of epoxy composites would be relatively weaker leading to the decrease of friction coefficient.