Analyses of abrasive wear behaviour in pin-on-plate tribo-system for several materials

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Extruded and injection moulded virgin PA 6/6 as abrasion resistant material

Polyamide (PA6/6) is often used as a tribological pair in abrasion prevalent applications such as hinges and sliders. PA6/6 is frequently processed by injection moulding and extrusion process. It is known that these processes influence the polymers mechanical behaviour, but their influence on the polymers wear response has not been studied. Hence the present research attempts to study the influence of different manufacturing processes on tribological behaviour for PA6/6. Wear tests were performed on a pin abrading tester (DIN 50322). Abrasion resistance of both extruded and injection moulded PA6/6 were tested at different loads (20 and 35 N). Single-pass (nonoverlapping mode) and multipass testing (overlapping mode) were used to understand the influence of clogging of wear debris. It is evidenced that with increasing load the specific wear rate decreases; moreover, fine abrasives tend to reduce the wear rate. In multipass testing a transfer layer clogged on the counterface that acted as a protective agent and lowers wear rate. Poor mechanical strength of injection moulded polymers is apparently compensated by microstructural response for having a similar wear behaviour between extruded and injection moulded PA 6/6. Hence a proper balance between microstructural and mechanical characteristics is an absolute must in PA 6/6 for better wear performance

Tribological characteristics of cast polyamide 6 (PA6G) matrix and their composite (PA6G SL) under normal and overload conditions using dynamic pin-on-plate system

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Tribological analysis of engineering plastics/steel friction pairs

© The Indian Institute of Metals - IIM 2021. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1007/s12666-021-02231-8This study involves the case of polymer–metal contact, where deformation and strain behavior play a significant role. In present work, a section of polymer gear is mated against steel gear, and the friction behaviors for different groups of polymer materials of PA 6G, PA 6G Mg, POM-C, PETP/PTFE, PA 66 GF 30 and Bakelite were experimentally studied. From the results obtained, all the materials coefficient of friction decreased significantly at the pitch point. This was attributed to the pure rolling at the pitch point and tangential traction, which was the dominant mechanism for resistance to motion. An unstable friction characteristic from flank tooth to the pitch point was evident in the low load conditions.Peer reviewe