Potential Joint Damage in a REBCO MRI Magnet Due to the Gradient Coil-Induced Vibration

This study investigates the potential for joint damage in REBCO MRI magnets due to mechanical vibration induced by gradient coil operation. A 6 T REBCO MRI magnet, developed as part of the Korea Medical Device Development Fund (KMDF) project, was analyzed to assess its susceptibility to gradient coil-induced vibrations. The eigenfrequency range of the magnet was identified to be within 1,787–2,000 Hz, which overlaps with the operational frequency range of the gradient coil (1–2,000 Hz). Simulations using a simplified two single pancake (SP) coil model revealed that peak stress levels at the joints could reach up to 700 MPa during resonance, approaching the tensile limit of REBCO tapes. The study suggests operating the gradient coil at frequencies at least 500 Hz away from the identified resonance range to prevent potential joint damage. Additionally, the use of wider joints between SP coils is recommended to concentrate resonance frequencies, making it easier to avoid dangerous operating conditions.