Evaluation of the Microstructure and High Temperature Wear Behavior of Cast Iron/Tungsten Carbide Surface Composite for using in Rollers

Roller tables, rollers, and pinch rolls are widely used in rolling mills, sheet metal works, and ceramic and tile production industries where harsh working conditions, like heating furnaces with high temperatures, oxide debris, and ceramic materials, have been a matter of concern. High wear-resistant cast iron is a common material for manufacturing these tools. The present study evaluates the production of cast iron-based matrix surface composites reinforced with tungsten carbide (WC) as a surface metal matrix composite (SMMC) using a centrifugal casting process. To that end, the sample microstructure was characterized using optical microscopy (OM) and scanning electron microscopy equipped with energy dispersive X-Ray spectroscopy (SEM-EDX). A 3-mm thick composite layer was formed on the sample surface. Within the composite layer, WC particles were homogeneously distributed in the pearlitic and iron carbide matrix, significantly increasing surface hardness. The wear behavior of fabricated SMMC was evaluated against base metal samples produced under similar conditions: ambient temperature (25 °C) and the average roller temperature in the furnace under normally applied loads of 100, 150, and 200 N (450 °C). The formation of a composite structure on the surface dramatically improved the wear resistance of cast iron, thus decreasing the weight loss of composite samples by 61% after a 1000 m sliding distance at 25 °C compared to non-composite samples. The production of cast iron-based matrix surface composite reinforced with WC using centrifugal casting, as a feasible and acceptable process, could be a promising and cost-effective solution to improve the performance of rollers in rolling lines and even hot rolling mill rolls.