Design and performance evaluation of a directional internal-cooling grooved grinding wheel with optimized coolant supply structure

Abstract

To enhance thermal management and optimize coolant efficiency in the peripheral grinding of superalloys, a novel internal-cooling grinding wheel incorporating a directional structural design was developed. The pressurized coolant is delivered to the grinding zone via an integrated system comprising the pipework, tool holder, and symmetrically arranged manifold ports. This symmetrical manifold port configuration enables precise and efficient control of coolant distribution. Through optimization of the symmetrical manifold port positioning using Computational Fluid Dynamics (CFD) simulations, the internal flow field of the grinding wheel was enhanced, resulting in increased outlet flow rates, improved distribution uniformity, and higher effective flow rates. Additionally, cubic boron nitride (CBN) abrasive rings featuring varying groove structures were fabricated via an electroplating process. A vertical peripheral grinding test platform incorporating directional internal cooling was developed to perform grinding experiments on superalloys. The experimental results demonstrated that, compared to conventional flood cooling, directional internal cooling achieved a reduction in grinding temperature by up to 16.9%, a decrease in surface roughness by up to 14.8%, and a reduction in workpiece surface microhardness by up to 6.11%, under equivalent coolant flow rate conditions. Among the tested configurations, the parallel slot design under directional internal cooling yielded the lowest grinding temperature and minimal surface microhardness, exhibiting reductions of 22.7% and 7.12%, respectively, compared to the non-slotted structure. This performance surpassed that of the diagonal slot, V-shape slot, and non-slotted configurations. However, a marginal degradation in surface morphology was observed for the slotted structures relative to the non-slotted design.