Enhancing Performance of Metal-Bonded Diamond Grinding Wheels for Machining Cemented Carbides through Graphite and Chromium Additions

Metal-bonded diamond grinding wheels for machining cemented carbides are characterized by high hardness and thermal conductivity but also by low porosity and limited dressability. The addition of graphite to these bonds deliberately weakens the bond, improving dressing behaviour while simultaneously reducing bond friction. The influence of sintering parameters and the addition of graphite flakes with varying particle sizes on the grinding layer properties is investigated. Furthermore, the addition of chromium is examined and leads to an additional increase in the critical bond strength of the grinding layer. Subsequent examination of the performance of the manufactured grinding layers with chromium and graphite additions demonstrates improved grinding force ratios. Graphite’s lubricating properties and enhanced coolant delivery contribute to improved grinding force ratios, especially in wheels with higher graphite content. Grinding wheels without graphite exhibit the lowest initial grinding force ratios and lack a self-sharpening mechanism. These findings highlight the complex interplay between graphite content, chromium addition, and particle size in optimizing grinding wheel performance.