Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets

Abstract

Listen

Translate article

The original goal of this Phase II Superconductivity Partnership Initiative project was to build and operate a prototype Magnetic Resonance Imaging (MRI) system using high temperature superconductor (HTS) coils wound from continuously processed dip-coated BSCCO 2212 tape conductor. Using dip-coated tape, the plan was for MRI magnet coils to be wound to fit an established commercial open geometry, 0.2 Tesla permanent magnet system. New electronics and imaging software for a prototype higher field superconducting system would have added significantly to the cost. However, the use of the 0.2 T platform would allow the technical feasibility and the cost issues for HTS systems to be fully established. Also it would establish the energy efficiency and savings of HTS open MRI compared with resistive and permanent magnet systems. The commercial goal was an open geometry HTS MRI running at 0.5 T and 20 K. This low field open magnet was using resistive normal metal conductor and its heat loss was rather high around 15 kolwatts. It was expected that an HTS magnet would dissipate around 1 watt, significantly reduce power consumption. The SPI team assembled to achieve this goal was led by Oxford Instruments, Superconducting Technology (OST), who developed the method of producing commercial dip coated tape. Superconductive Components Inc. (SCI), a leading US supplier of HTS powders, supported the conductor optimization through powder optimization, scaling, and cost reduction. Oxford Magnet Technology (OMT), a joint venture between Oxford Instruments and Siemens and the world’s leading supplier of MRI magnet systems, was involved to design and build the HTS MRI magnet and cryogenics. Siemens Magnetic Resonance Division, a leading developer and supplier of complete MRI imaging systems, was expected to integrate the final system and perform imaging trials. The original MRI demonstration project was ended in July 2004 by mutual consent of Oxford Instruments and Siemens. Between the project start and that date a substantial shift in the MRI marketplace occurred, with rapid growth for systems at higher fields (1.5 T and above) and a consequent decline in the low field market (<1.0 T). While the project aim appeared technically attainable at that time, the conclusion was reached that the system and market economics do not warrant additional investment. The program was redirected to develop BSCCO 2212 multifilament wire development for high field superconducting magnets for NMR and other scientific research upon an agreement between DOE and Oxford Instruments, Superconducting Technology. The work t took place between September, 2004 and the project end in early 2006 was focused on 2212 multifilamentary wire. This report summarizes the technical achievements both in 2212 dip coated for an HTS MRI system and in BSCCO 2212 multifilamentary wire for high field magnets.