Superconductive-assisted machining (SUAM) is a polishing method that applies the magnetic flux-pinning phenomenon of a superconductor to a magnet tool with a polishing pad, thereby reducing tool interference. SUAM methods utilize two types of devices: a single magnet system and a double magnet system (DMS). The DMS increases the magnetic flux density by placing the lower magnet under the superconductor, resulting in higher polishing pressure. In our previous study, we used a superconducting ceramics bulk in a conventional SUAM system. In this study, superconducting tapes were combined with the superconducting ceramics bulk to increase the holding force of the SUAM system. Four types of superconductors using superconducting ceramics bulk and tape were evaluated using SMS to determine their structure as a function of magnet tool position. The maximum holding force was obtained when the superconductor was combined with the ceramics bulk and superconducting tape. The holding force was measured by varying the initial position of the lower surface magnet in the DMS. When the bottom magnet was placed 4 mm from the superconductor, the attractive force was 1.6 times greater than at a 20 mm distance. The polishing performance of aluminum in SUMA was evaluated using superconducting ceramics bulk and tape. A superconducting tape can accommodate greater polishing pressure, resulting in higher polishing efficiency. After polishing, a surface roughness of Sa<0.1 µm was obtained with reduced polishing pressure.

1. [1] M. Sudo, “Advanced control technologies for 5-axis machining,” Int. J. Automation Technol., Vol.1, No.2, pp. 108-112, 2007. https://doi.org/10.20965/ijat.2007.p0108
2. [2] L. Silva, H. Yoshioka, H. Shinno, and J. Zhu, “Tool orientation angle optimization for a multi-axis robotic milling system,” Int. J. Automation Technol., Vol.13, No.5, pp. 574-582, 2019. https://doi.org/10.20965/ijat.2019.p0574
3. [3] T. Suzuki, K. Yoshikawa, T. Hirogaki, E. Aoyama, and T. Ikegami, “Improved method for synchronizing motion accuracy of linear and rotary axes under constant feed speed vector at end milling point – Investigation of motion error under nc-commanded motion –,” Int. J. Automation Technol., Vol.13, No.5, pp. 679-690, 2019. https://doi.org/10.20965/ijat.2019.p0679
4. [4] T. Saiki, M. Tsutsumi, H. Suzuki, M. Kouya, and M. Ushio, “Development of measurement for motion accuracy of 5 axis nc machine tool,” Int. J. Automation Technol., Vol.2, No.2, pp. 111-118, 2008. https://doi.org/10.20965/ijat.2008.p0111
5. [5] A. I. Larkin and Y. N. Ovchinnikov, “Pinning in Type II Superconductors,” J. of Low Temperature Physics, Vol.34, Nos.3-4, pp. 409-428, 1979. https://doi.org/10.1007/BF00117160
6. [6] J. Bardeen, L. N. Cooper, and J. R. Schrieffer, “Theory of superconductivity,” Physical Review, Vol.108, No.5, pp. 1175-1204, 1957. https://doi.org/10.1103/PhysRev.108.1175
7. [7] Y. Tanaka, H. Nakashima et al., “Study on polishing method using magnetic levitation tools with superconductivity,” J. of the Japan Society for Abrasive Technology (JSAT), Vol.62, No.4, pp. 219-220, 2018 (in Japanese). https://doi.org/10.11420/jsat.62.219
8. [8] K. Suzuki and T. Nakasaki, “Study on polishing method using double magnet system by superconductive assisted machining method,” Proc. of LEMP2020, 2020.
9. [9] H. Nakashima, K. Suzuki et al., “Study on polishing method using magnetic levitation tool in superconductive-assisted machining,” Int. J. Automation Technol., Vol.15, No.2, pp. 234-242, 2021. https://doi.org/10.20965/ijat.2021.p0234
10. [10] M. Tinkham and C. J. Lobb, “Physical properties of the new superconductors,” Solid State Physics, Vol.42, pp. 91-134, 1989. https://doi.org/10.1016/S0081-1947(08)60080-6
11. [11] H. B. Radousky, “A review of the superconducting and normal state properties of Y1-xPrxBa2Cu3O7,” J. of Materials Research, Vol.7, No.7, pp. 1917-1955, 1992. https://doi.org/10.1557/JMR.1992.1917
12. [12] M. K. Wu et al., “Superconductivity at 93 K in a new mixed-phase Yb-Ba-Cu-O compound system at ambient pressure,” Physical Review Letters, Vol.58, No.9, pp. 908-910, 1987. https://doi.org/10.1103/PhysRevLett.58.908
13. [13] D. He et al., “Spatial and temporal flux-trapping properties of bulk high temperature superconductors under static magnetization fields,” J. Supercond. Nov. Magn., Vol.28, pp. 2385-2391, 2015. https://doi.org/10.1007/s10948-015-3071-0
14. [14] J. R. Hull, “Superconducting bearings,” Superconductor Science and Technology, Vol.13, No.2, pp. R1-R15, 2000. https://doi.org/10.1088/0953-2048/13/2/201
15. [15] Y. Arai, H. Seino, and K. Nagashima, “Levitation properties of superconducting magnetic bearings using superconducting coils and bulk superconductors,” Superconductor Science and Technology, Vol.23, No.11, Article No.115011, 2010. https://doi.org/10.1088/0953-2048/23/11/115011
16. [16] J. Wang et al., “The first man-loading high temperature superconducting maglev test vehicle in the world,” Physica C: Superconductivity and its Applications, Vols.378-381, No.PART 1, pp. 809-814, 2002. https://doi.org/10.1016/S0921-4534(02)01548-4
17. [17] L. Schultz et al., “Superconductively levitated transport system-the supratrans project,” IEEE Trans. on Applied Superconductivity, Vol.15, No.2, pp. 2301-2305, 2005. https://doi.org/10.1109/TASC.2005.849636
18. [18] L. Rossi, “The LHC superconducting magnets,” Proc. of the 2003 Particle Accelerator Conf., Vol.1, pp. 141-145, 2003. https://doi.org/10.1109/PAC.2003.1288863
19. [19] Y. Hiramatsu, E. S. Otabe et al, “Evaluation of magnetic cutting and polishing with superconducting bulks,” J. of Physics, Conf. Series, Vol.871, Article No.012048, 2017. https://doi.org/10.1088/1742-6596/871/1/012048
20. [20] N. Yamachi, T. Nishikawa, N. Sakai, K. Sawa, and M. Murakami, “Levitation forces of bulk superconductors in varying fields,” Physica C: Superconductivity, Vols.392-396, pp. 579-584, 2003. https://doi.org/10.1016/S0921-4534(03)01344-3
21. [21] T. Nakasaki, Y. Kinoshita, P. Khajornrungruang, E. S. Otabe, and K. Suzuki, “Study on polishing method using double magnet system by superconductive assisted machining,” Int. J. Automation Technol., Vol.15, No.4, pp. 503-511, 2021. https://doi.org/10.20965/ijat.2021.p0503