Dry sliding wear behaviour of Industrial semi-crystalline and crystalline polymers

Abstract: At present, polymers are used in many static and dynamic industrial applications such as bushes, gears, bearings, rollers, timing screws and washers having replaced traditional materials like steel brass, bronze, copper and aluminum which undergo wear and tear. The present investigation was made to study the adhesive wear characteristics of semi-crystalline polyurethane polymer and crystalline polyacetal (Polyoxymethylene-POM) polymer. Polymers considered for this study are potential materials for rollers in hybrid chains in food processing industry and medical equipments. The wear tests were performed under dry conditions using a pinon-disc (ASTM G99) arrangement against a mild steel disc (HRB 67) at room temperature under various loads (60, 80,100N) and sliding speeds (1.8, 2.3, 2.8 m/s). Cylindrical shaped polymers of 25 mm diameter were used for the wear tests. Polyacetal was observed to have the lesser wear rate and coefficient of friction irrespective of load and speed because of its crystalline nature. Polyurethane exhibits higher frictional coefficient at higher sliding velocity