الفهرس 
CHAPTER ONE : INTRODUCTION AND LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
High density polyethylene (HDPE) and low density polyethylene (LDPE) are widely used as a bearing material in industrial application because of its low weight and cost. Reinforcing polymers with the appropriate reinforcements is an effective way to obtain a variety of enhanced material properties. High density polyethylene (HDPE) and low density polyethylene (LDPE) were reinforced by Copper wires with different diameters to improve the tribological properties of the composite material.
The present work investigates friction and wear displayed by the scratch of low density polyethylene (LDPE) and high density polyethylene (HDPE) composites reinforced by unidirectional continuous copper wires. This is a simulation of bearing material. Influence of heat treatment processes such as (annealing, hardening and tempering) on their friction and wear was studied.
Based on the experimental observations, it was found that friction coefficient displayed by the scratch of LDPE and HDPE reinforced by copper wires decreased with increasing number of wires. The increase of diameter of the copper wires caused significant friction decrease. The influence of heat treatment of test specimens on their friction and wear was investigated. Friction coefficient displayed by both LDPE and HDPE composites reinforced by unidirectional continuous copper wires recorded lower friction for tempered test specimens followed by hardened and annealed ones. Tempered specimens displayed the lowest friction values, while specimens without heat treatment showed the highest values. By annealing at 90 °C and hardening at 120 °C, friction coefficient significantly increased with increasing normal load while it decreased by tempering at 110 °C for both HDPE and LDPE reinforced by copper wires.
Wear scar width of the tested composites slightly decreased with increasing number and diameter of wires. Wear followed the same trend of friction coefficient, where annealed specimens displayed relatively higher wear scar width than hardened and tempered tested composites. The specimens without heat treatment displayed the highest wear scar width while tempered recorded the lowest values.
High density polyethylene (HDPE) composites showed low fraction and wear than that observed for low density polyethylene (LDPE) composites.