Grinding Wheel Wear And Grinding Force In Cup-Wheel Spherical Grinding Process

In the high hardness spherical precision grinding, the wheel’s wearcould lead to the change of the grinding environment and have greatinfluence on the surface quality. And there is important relationshipbetween the grinding force and grinding wheel wear. It will be easier tocontrol the grinding force and grinding process through the research of therelationship. So, this work present the grinding wheel wear and thegrinding force using ceramic bond CBN cup wheel, and the mutualinfluence between them.The structure and characteristics of the block cup wheel wereintroduced based on the spherical grinding principle. Experimentalresearch presented the wheel’s wear in spherical grinding. The surface ofworn wheel was observed through the SEM experiment, and the forms andmechanism of wheel wear were analyzed, which showed that there wereabrasive wear, local fracture, abrasive shedding and adhesive wear. In theinitial stage, the main wear forms were local fracture and abrasiveshedding. When the contact area increased as the wear, the main formswere abrasive wear and adhesive wear.The shape of the worn grinding wheel was discussed on the principleof the sphere generating method. The worn surface of the grinding wheelis namely the inner sphere tooled by the ball. The curvature of the shape isdecided by the curvature of ball. The mathematic model was built for thecalculation of the amount of wheel wear and the contact area betweenwheel and workpiece. The wear rate and the influential factors on the wearwere analyzed. And the experiments verified the theory model. The number of effective abrasive grains and the thickness ofundeformed chip were analyzed based on the grinding geometry.Considering the influence of the grinding wheel wear, the mathematicalmodel of grinding force was derived, which is mainly the function of thefeed amount and the grinding wheel wear. And then the mathematicalmodel was validated by the experiment.