In recent year, there has been remarkable progress in the use of high-field rare-earth barium copper oxide (REBCO) coils in NMR, MRI, and accelerator applications. No-insulation (NI) winding techniques are adopted to achieve high thermal stability and high current density. Thus, each winding in a non-impregnated NI REBCO coil can deform separately and move freely because of the thermal strain...
The high-field magnets experience the large amount of mechanical stress as a result of Lorentz forces. During the magnetization of the coil, strong Lorentz forces give rise to hoop stress, which can cause mechanical failure, resulting in the degradation of the coil performance. A recent study led to the discovery that scratching the GdBCO-coated conductor (CC) tapes ameliorated the degradation...
REBCO wires have high thermal stability and high current density, therefore, it is expected to be applied to high magnetic field magnet for NMR, MRI, and accelerators. On the other hand, there is the problem such as mechanically deteriorations and damages of REBCO coils. Because REBCO wires are tape shape, when charging and discharging, screening currents are induced to circulate in the...
High-temperature superconducting (HTS) magnets have been widely used in the fields of electricity, transportation, medicine, and scientific experiment. However, HTS magnets generally suffer from the thermal stress and electromagnetic stress during manufacture and operation, deteriorating its mechanical properties as well as restricting its further development. This study is aimed at improving...
Stress managed magnet designs are being developed to limit the strain and stresses applied to the conductor during powering. The canted cos $\theta$ (CCT) design is one of the proposed solutions. In this design, the conductor is wound around a mandrel: the impregnation process creates a bonding between the two, that can fail when the magnet is powered. The energy releases consequent to the...
Abstract: The YBCO superconducting coils will cause complex deformation, and even moving between layers under the large Lorentz forces during energization. These will further disturb the magnetic field quality and the operating safety and stability. A more accurate estimation of the magneto-mechanical behaviors of YBCO coil during excitation is a crucial one. However, the conventional finite...
