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چکیده
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Tribology which deals with the fundamental interaction of materials has robust link with morphological modification of contacting surfaces. Hence, adequate information on surface modification is essential for an effectual design of tribological system. Amongst different existing materials, polymer-metal pairs are commonly used in bearings, rollers and gears. Tribological interaction of this tribo-pair requires ample understanding of its surface responses. Generally, these surfaces are studied using traditional post-mortem analysis based on macro- and micrographs (qualitative), and roughness (quantitative) changes. These conventional techniques do not capture critical information such as “evolution” of morphological features. Nevertheless, with the recent advancements in electronic imaging, the morphological changes of moving surface are studied in real-time at a micro scale. In our investigation, a polymer-metal pair is studied for its surface evolution under Hertzian line contact using a high speed online vision system. The acquired real time images are segmented and processed in order to segregate the surface scars produced by wear mechanisms such as abrasion, adhesion and fibre damage. The quantitative estimate of these surface scars from the segmented images represents an evolution curve of surface morphology. Furthermore, the online vision monitoring reveals that the conformal contact has been established through breaking of asperities followed by plastic flow of polymers. Once, after achieving the conformity in contact surfaces at the steady stage, dynamic mechanisms such as back transfer of polymers from steel surface and plastic flow are observed for obtaining a clear understanding of the wear process. Additionally, the blur of the acquired images due to the wear process serves as a quantitative estimate for wear. The evolution curves together with friction, wear, and temperature response provides complete understanding of the tribological process. This comb
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