Speaker
Description
The delamination problem of the epoxy-impregnated REBCO coils was always an obstacle for REBCO magnet application. To avoid the delamination, recently a novel method that coating release agent layers on the REBCO tapes was proposed, and it has been preliminarily verified by REBCO coils impregnated room-temperature curing epoxy (Stycast 2850). For thermosetting epoxy, like IR3 (supplied by Technical Institute of Physics and Chemistry, CAS), silicon release agent was selected as the appropriate material to be coated on the REBCO tapes. The bonding strengths of the interface between the IR-3 epoxy and REBCO tape surface were measured both at room temperature and 77 K. Then several different-radius IR3-impregnated REBCO coils wound by release agent coating REBCO tapes was tested in liquid nitrogen, compared with the controlled coils without any epoxy and release agent, to verify the effectiveness of this method. During the cooling process, the strain inside the IR3- impregnated REBCO coils was measured by Bragg grating fiber sensors or strain gauges, which was compared with the FEM simulation results. The strain during IR3 epoxy curing process was also measured, which indicated there would be intrinsic strain inside the impregnated REBCO coils after curing.
Acknowledgement
This work is supported by the Fundamental Research Funds for the Central Universities lzujbky-2024-jdzx02, the Open Fund of Magnetic Confinement Fusion Laboratory of Anhui Province 2024AMF04002, and the National Natural Science Foundation of China under Grants 52277026
