Currently, the demand for carbon fiber reinforced plastic (CFRP) has increased in various fields. However, there have been few studies investigating the machined surface quality, degradation in CFRP mechanical properties with machining temperature, or machining tool cost. In particular, the machining temperature is considered to affect the machined quality because the CFRP matrix is a resin. In this study, a cubic boron nitride (cBN) electroplated end mill was developed; this novel tool can switch between cutting and grinding without needing to change the tool. To observe the relationship between the amount of abrasive grain in contact with the CFRP and the occurrence of burrs, a grinding test was conducted with different clearance angles of the end mill and different abrasive grain sizes. The temperature during the grinding processes was measured, and the burrs were estimated after the grinding processes. From these results, the contact amount of the abrasive grit suitable for grinding was derived.

1. [1] R. Kozarsky, A. Vicari, and M. Holman, “Stronger, Lighter, Faster…Cheaper? How Innovation Will Affect Carbon Fiber’s Cost and Market Impact,” State of the Market Report, 2012.
2. [2] A. Kitano, “Carbon Fiber Composite Materials Supporting Weight Reduction of Aircraft,” Chemistry and Education, Vol.59, No.4, pp. 226-229, 2011 (in Japanese).
3. [3] S. Abrate and D. A. Walton “Machining of composite materials. Part I: Traditional methods,” Compos. Manuf., Vol.3, No.2, pp. 75-83, 1992.
4. [4] W. König, C. Wulf, P. Grass et al., “Willerscheid, Machining of fiber-reinforced plastics,” CIRP Annals, Vol.34, No.2, pp. 537-548, 1985.
5. [5] J. Davim and P. Reis, “Study of Delamination in Drilling Carbon Fiber Reinforced Plastics (CFRP) Using Design Experiments,” Composite Structures, Vol.59, pp. 481-487, 2003.
6. [6] M. Haddad, R. Zitoune, F. Eyma et al., “Study of the surface defects and dust generated during trimming of CFRP: influence of tool geometry, machining parameters and cutting speed range,” Composites Part A: Applied Science and Manufacturing, Vol.66, pp. 142-154, 2004.
7. [7] M. Haddada, R. Zitoune, H. Bougherara et al., “Study of trimming damages of CFRP structures in function of the machining processes and their impact on the mechanical behavior,” Composites Part B: Engineering, Vol.57, pp. 136-143, 2014.
8. [8] A. Koplev, A. Lystrup, and T. Vorm, “The cutting process, chips, and cutting forces in machining CFRP,” Composites, Vol.14, pp. 371-376, 1983.
9. [9] T. Hirogaki, E. Aoyama, K. Ogawa, T. Otsuka, and S. Nojiri, “Consideration of thermal damage and optimum processing conditions of ultra-small diameter drilled holes in printed circuit boards using ultra high speed spindles,” Proc. of the Japan Society of Mechanical Engineers (C edition), Vol.74, No.743, pp. 214-220, 2008.
10. [10] T. Hirogaki, E. Aoyama, N. Katayama, H. Nakagawa et al., “Monitoring of Micro Drilling Phenomena of Printed Circuit Boards by Infrared Thermography: On Drilling Temperature during Processing of Aramid Fiber Reinforced Substrate,” Material, Vol.53, No.5, pp. 553-559, 2004.
11. [11] I. Paul, T. Rajakumar, P. Hariharan, and L. Vijayaraghavan, “Drilling of carbon fibre reinforced plastic (CFRP) composites – a review,” Int. J. of Materials and Product Technology, Vol.43, No.1/2/3/4, pp. 43-67, 2012.
12. [12] K. Y. Park, D. G. Lee, and T. Nakagawa, “Mirror surface grinding characteristics and mechanism of carbon fiber-reinforced plastics,” J. Mater. Process. Technol., Vol.52, pp. 386-398, 1995.
13. [13] K. Y. Park, J. H. Choi, and D. G. Lee, “Delamination-free and high efficiency drilling of carbon fiber reinforced plastics,” J. Compos. Mater., Vol.29, No.15, pp. 1988-2002, 1995.
14. [14] T. Inoue, M. Hagino, M. Natsui, and W. L. Gu, “Cutting Characteristics of CFRP Materials with End Milling,” Key Engineering Materials, Vols.407-408, pp. 710-713, 2009.
15. [15] R. Kometani, Y. Kabaya, T. Hirogaki, E. Aoyama, and T. Furuki, “Consideration of Phenomena in Side Cutting of CFRP Using CBN Electrodeposition End Mill Tool,” The Japan Society for Precision Engineering, pp. 995-996, 2017 (in Japanese).
16. [16] H. Arisawa, S. Akama, and H. Niitani, “High-performance cutting and grinding technology for CFRP (carbon fibre reinforced plastics),” Mitsubishi Heavy Industries Technical Review, Vol.49, No.3, pp. 3-9, 2012.
17. [17] T. Furuki, Y. Kabaya, T. Hirogaki, E. Aoyama et al., “Influence of cBN electroplated end-mill shape on CFRP machining,” J. of the Japan Society for Precision Engineering, Spring, pp. 685-686, 2016 (in Japanese).
18. [18] K. Yugo, T. Hirogaki, E. Aoyama, T. Furuki et al., “Development of cBN electrodeposition end mill type tool for CFRP machining,” Proc. of the Japan Society for Precision Engineering Autumn Meeting, pp. 365-366, 2016.
19. [19] T. Kaneeda, “CFRP cutting mechanism,” Trans. N. Am. Manuf. Res. Inst. SME, Vol.19, pp. 216-221, 1991.
20. [20] N. Bhatnagar, N. Ramakrishnan, N. K. Naik, and R. Komanduri, “On the machining of fibre-reinforced plastic (FRP) composite laminates,” Int. J. Mach. Tools Manuf., Vol.35, pp. 701-716, 1995.
21. [21] Y. Kabaya, T. Furuki, T. Hirogaki, E. Aoyama et al., “Influence of grit size in high speed milling of CFRP with cBN electroplated end-mill,” J. of the Japan Society for Precision Engineering, pp. 405-406, 2015 (in Japanese).
22. [22] H. Nakagawa, K. Ogawa, A. Kihara, T. Hirogaki et al., “Improvement of micro-drilled hole quality for printed wiring boards,” J. of Materials Processing Technology, Vol.191, Issues 1-3 pp. 293-296, 2007.