Improving the grinding performance of high-speed rail grinding stone via mixed granularity of zirconia corundum

High-speed rail grinding stones (GS) were fabricated using zirconia alumina (ZA) with five mass ratios of F16 to F30 to explore the regulatory mechanism of abrasives with mixed granularity on the grinding performance. With the decrease of abrasive grit size, the enhanced abrasive crushing strength can control the grinding behaviors of GS. GS with low mass ratio of F16 to F 30 gave the largest grinding amount (4.0 g) and grinding ratio (46.2), and the largest amounts of scratches on the rail surface, evincing that the fiercest grinding actions were realized via the mixed granularity, the improved strength and grinding capacity. A grinding equilibrium state was achieved via attrition-wear/micro-fracture of F16 and attrition-wear/pulled-out of F30, thus offering the best self-sharpness of GS.