Prediction model of profile error induced by wheel wear in outer contour grinding of Si3N4 spherical rollers

During the outer contour grinding of silicon nitride (Si ₃ N ₄ ), the material's hard and brittle properties significantly accelerate the wear of diamond grinding wheels. This necessitates frequent wheel dressing during machining, thus rendering grinding wheel wear a pivotal factor in determining the contour accuracy and surface finish of the roller's external cylindrical surface. In conventional practice, dressing strategies are predominantly empirical, and the underlying mechanism by which wheel wear induces profile errors remains insufficiently elucidated. To address these challenges, a profile error prediction model was developed based on grinding ratio theory, specifically incorporating the radial wear of the grinding wheel. Taking the cumulative number of processed rollers as the independent variable, the influences of roller geometry, wheel specifications, and grinding parameters on the evolution of profile errors were systematically investigated. Experimental validation demonstrated that the maximum deviations between the predicted and measured values for wheel radial wear ( ∆R ) and profile error ( ∆ε ) were 17.605% and 13.612%, respectively. These results confirm that the proposed model provides a robust theoretical framework for optimizing dressing schedules and process parameters in the precision grinding of Si ₃ N ₄ spherical rollers.