Fabrication of Electroplated CBN End-Mill for High-Efficiency Face Milling of Carbon Fiber Reinforced Plastic

Carbon fiber reinforced plastic (CFRP) was developed in the 1960s. Since then, it has been used in various fields. Accordingly, the number of studies related to machining of CFRP has been increasing (e.g. cutting, laser processing, or abrasive water jet machining). However, these studies have been focusing on the trimming of surplus portions or drilling. In addition, the degradation of mechanical properties due to the heat induced during machining has not been sufficiently considered. Furthermore, another issue is the cost involved, such as tool and equipment costs. This makes several of these proposed methods tremendously expensive. Therefore, in this study, electroplated end-mills with electrodeposited cBN or diamond grains of different grit sizes (the mesh size are #600, #1000, #1500 and #2000) are fabricated. As a result, the cost of the electroplated tool will decrease by 2/3 compared to general diamond-coated tools. Moreover, the flat cutting of CFRP is often carried out with these fabricated tools and with general diamond-coated tools. In cases where the fabricated tools are used, the machined CFRP products are burr-free or nap-free. Additionally, the induced CFRP temperature during cutting decreases compared to the case of diamond-coated tools. From these results, the optimum grit size was determined to be #1000. On the other hand, end-mills with deposited cBN or diamond grains, fixed on the tip of the fabricated tool, occasionally dropped out after a few paths. Therefore, efforts are presented to improve the tool tip shape and minimize its grain dropout rate. Based on such improved characteristics, the electrodeposited end-mill is expected to be able to machine CFRP more effectively.