Fabrication of Micro Ni-W Electroplated Diamond Tools and Their Application to Grooving of Brittle Materials : Improvement of Tool Quality and Machining Performance

The present paper intends to improve the tool quality and the machining performance of micro cylindrical Ni-W electroplated diamond tools. From the grooving tests of silicon the following results were obtained. The scatter of diamond grit density on the tool surface can be prevented through the intermittent pouring of electroplating solution into the solution with grit supported by a filter. Ni strike plating before electroplating is useful for extending the tool life, but it can result in the degradation of roughness on groove side surface. Tool wear may result from the removal of bond material due to generated chip and dropped diamond grit, therefore the usage of harder bond material and the heat treatment of bond material are recommended. For a constant tool diameter there exists a suitable grit diameter from the viewpoint of machining efficiency and groove roughness. In grooving of quartz glass, chippings of 10-20μm may occur on the groove edges, which can be prevented by the application of axial ultrasonic vibration to the tool.