Ultrasonically Assisted Machining for Mirror Finishing of Die (1st report)

Abstract

Dies for injection molding parts such as cellular phones and light conductive parts require a high quality surface finish in terms of both appearance and integrity. Manual finishing is an important die manufacturing process, which decides the surface roughness of a die and influence the accuracy of its shape. However, manual polishing consumes several days to finish the die surface. Therefore, high precision die milling or grinding are required that improve surface roughness, in order to minimize polishing operation. In the previous report, ultrasonically diamond grinding experiments were carried out to confirm ultrasonically oscillation effect for die steel face grinding. And mirror surface was obtained. However, tool form error and run-out prevent 3D form mirror grinding. Because high shape accuracy tools are essential for high precision 3D form grinding. This paper provides results of toolmaking and performances of electroplated tools in ultrasonically assisted grinding. Electroplated tools can perform ultrasonically assisted face grinding and ground surface has roughness 0.24μmRz.