الفهرس 
Chapter One: IntroductionOnly 14 pages are availabe for public view
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Abstract
The friction and wear of polymer matrix composites reinforced byunidirectional continuous metallic wires are discussed in this work. The friction and wear, of polymer matrix composites consisting of polyethylene and polystyrene matrix reinforced by unidirectional continuous circular wires of copper and steel were tested.
On the basis of experimental results, it was found thatfriction coefficient displayed by the scratch of PE and PP reinforced by the tested metallic wires decreased with increasing number of metallic wires. As the load increased friction coefficient increased. It seems that the presence of metallic wires decreased the hardness of the polymeric materials so that the material removal by the indenter was easier. The effect of the wire diameter on friction coefficient had no effect for PE reinforced by copper wires. Friction coefficient displayed by the scratch of PP showed relatively higher values than that observed for PE. It decreased with increasing the wire diameter.
Copper wires reinforcing PE experienced decreasing wear trend with increasing number of wires. Normal load showed significant effect on wear of PE, where the variations were more pronounced. The increase of the number of steel wires reinforcing polymeric materials caused significant wear decrease. Increasing the wires diameter of steel and increasing their number caused wear decrease. Wear of PP matrix reinforced by wires of copper slightly decreased with increasing number of wires. Variation of wire diameter showed insignificant effect on wear. Wear significantly increased with increasing normal load. Wear displayed by the scratch of PP reinforced by steel wires showed lower wear than that observed for PP reinforced by copper wires. Wear values were influenced by the variation of steel wire diameter due to the variation of the cooling rate.
The decrease in friction coefficient and wear may be attributed to the fact that, the metallic wires as good heat conductor transferred heat during molding out of the polymeric materials. This process increased the rate of cooling causing softening of the matrix. This effect is considered as result of crystal phase change in the structure, where the elastic part of polymer viscoelasticity decreased causing significant decrease in themicrohardness of the tested polymeric materials.