Effects of Grain Size and Operating Parameters on the Mechanics of Grinding

An investigation is described of the effects of grain size and operating parameters on the mechanics of grinding. Results indicate that the specific cutting energy in grinding, which is the total specific grinding energy minus the specific energy due to sliding between the wear flats and the workpiece, is independent of grain size and decreases with increasing table speed and downfeed. It is postulated that the specific cutting energy consists of chip forming energy which is independent of table speed and downfeed, and plowing energy which decreases with increasing table speed and downfeed. Results for G-ratio, surface finish, and burning conditions are also presented. Of particular interest are the effects of grain size on burning conditions. With finer grain size, burning occurs at larger wear flat area and energy input per unit area ground, but the G-ratio and grinding wheel tool life are less. This is related to increased attritious wear with finer grains.