Recently high field magnet coil especially for MRI, NRM and especially fusion strongly demand low-cost REBCO tape. Sumitomo Electric Industries, Ltd. (SEI) has been developing REBCO tape fabrication by Fluorine-free MOD (FF-MOD) method which is a promising technique for low cost REBCO fabrication. This is because inexpensive and easily prepared solutions can be used, there is a nearly 100% material yield, and no special energy source is required except for a conventional tube furnace. It used to be hard to include artificial pinning centers (APCs) in the process needed for high magnetic field applications. However, we recently reported success in making FF-MOD films with BaMO3 (BMO, M = Hf, Zr, etc.) nanoparticles as APCs by applying a poly-crystallization sintering process along with other processes [1]. We developed BMO nanoparticles with a minimum diameter of 2 nm by utilizing the solvothermal method [2]. So far, we have succeeded in fabricating epitaxial REBCO films with BMO on a clad type tape with buffer layers and 120-m-long REBCO tapes with Ic exceeding 200 A/4 mm-width at 77 K have been achieved. The highest Ic at 20 K, 20 T (B//c) is 230 A/4 mm with 2.7 mol% BaHfO3. In addition, we have demonstrated high Ic potential of FF-MOD films on IBAD substrates [3]. The Ic of over 500 A/4-mm-width at 77 K has been achieved, which is expected to be over 180 A at (20 K, 20 T), meeting a fusion requirement. However, the texture requirement of IBAD-MgO template for FF-MOD has not been clarified. In this study, the REBCO films were fabricated various texture template of IBAD-MgO and the effect of its texture on critical current were investigated.

[1] T. Yoshihara et al., IEEE Trans. Appl. Supercond., 33 (2023) 6600205.
[2] N. Chamorro et al., RSC Adv., 10(2020) 28872.
[3] M. Inagaki et al., WB-6-5-INV, ISS2023, Nov. 29, 2023.