A Study of the Grinding Alumina for the Multi-Point Diamond Tools

The purpose of this paper is to investigate the performance of grinding alumina for the specific designed tools containing a controlled diamond protrusion and arrangement. The grinding forces, workpiece roughness and diamond wear at changing the depth of cut and feed under a fixed spindle speed were studied in the experiments. The experiment results showed that the grinding forces with the increase of feed slowly increased. However, the grinding forces with the increase of depth of cut showed a relatively larger rise. When the depth of cut reached to 0.09 mm that is about one fourth of diamond size, the axial grinding force obtained above about 20 N to cause some weaker or higher protrusive diamonds to produce a relatively larger fracture or pull-out. Furthermore, under a larger depth of cut and a larger feed rate the workpiece roughness obtained was the poorer. When diamond tool was employed for a longer time test under the depth of cut less than about one fourth of grit diameter, diamonds mainly displayed an attritious wear and the alumina roughness was about Ra 1.2-2.2 μm. This designed diamond tools are feasible for grinding alumina.