There are two types of hollow processing technology, one that processes before molding and the other that processes after molding. However, in hollow processing after molding, it is difficult to internally process an object which has a complicated shape. Therefore, SUAM (Superconductive-Assisted Machine) has been proposed in which a magnetic material is levitated to process an object by utilizing the magnetic flux pinning phenomenon of superconductors. In this study, we conducted electromagnetic field analysis using a simple model of only a permanent magnet and superconducting tapes, and sought a method to obtain a stronger repulsive force. [1]

In this study, as shown in Fig. 1, the model of the SUAM has six superconducting tapes placed radially at equal intervals from the center. Then, four layers similar to the upper layer were prepared under the superconducting tapes with the distances between the upper and lower layers at intervals of 50 mm, 100 mm, 300 mm, and 500 mm. Then, the permanent magnet was magnetized at the magnetizing position of 10 mm above the superconducting tapes. And the repulsive force from the superconducting tapes to the permanent magnet was calculated, when the permanent magnet was approached perpendicularly to the superconducting tapes. Then, the distance between the permanent magnet and the superconducting tapes was changed from 10 mm to 1 mm. Fig. 2 shows the FEM calculation results of the superconducting tapes with different layer spacing. From Fig. 2, the repulsive force is large when the distance between layers is short. However, the repulsive force decreases as the distance between the layers increases. From this result, it was found that it is important that the distance between layers is short in order to obtain a strong repulsive force.

[1] Nakashima H, Nakasaki T, Tanaka T, Kinoshita Y, Khajornrungruang P, Otabe E S and Suzuki K 2021 Int. J. of Automation Technology Vol. 15 No. 2, pp. 234-42

Keywords: SUAM(superconductive-assisted machining), Layer spacing