Low Cost Magnesium Diboride Superconducting Wire for 7 to 10 Tesla MRI Systems

描述（由申请人提供）：快速通道一期和二期的长期目标是开发一种低成本的高场超导体，可以使每天使用的6-8特斯拉临床MRI系统具有成本效益。这将有利于需要高分辨率和快速成像的MRI应用。这符合美国国立卫生研究院的使命，即向公众提供具有成本效益的改善医疗保健。该快速通道第一阶段和第二阶段提案的具体目标是在4 K时7-11特斯拉范围内显著改善MgB2超导体导线的性价比。目前，各种核磁共振成像生产商正在考虑7特斯拉范围内的临床核磁共振成像。在世界各地，为了研究目的，已经建造了7-9特斯拉范围内的核磁共振系统，每台耗资数百万美元。目前还没有一种经济的超导体线用于大容量、低成本、7-8特斯拉的MRI系统。7-8特斯拉范围内的高场MRI的进一步商业化将要求导线暴露在10-11特斯拉范围内的场中。不幸的是，这超出了NbTi超导体的磁场范围，NbTi超导体是商用1.5和3.0特斯拉（电线上为6特斯拉）MRI系统的主要超导体。虽然Nb3Sn超导体已经得到了改进，并在7到20特斯拉的高电场中运行，但这种电线仍然相当昂贵，以每千安培计7-11特斯拉的价格是6特斯拉的NbTi线的4到6倍。Hyper Tech公司预测，在7-11特斯拉的情况下，MgB2导线的价格与在6特斯拉的情况下的NbTi导线的价格接近。这是基于不同研究者的实验工作，获得了超过35特斯拉的Bc2，各种薄膜研究工作在4.2 K时产生了1,000,000 A/mm2的电流密度，在10特斯拉时产生了超过1000 A/mm2的电流密度。如果这种类型的性能可以在散装导线中获得，那么MgB2的低性价比可能使低成本的6-8特斯拉临床MRI系统成为可能。在快速通道I期和II期，我们打算通过改进制造、改进硼粉制造和改进高温绝缘来实现这些目标。快速通道一期和二期将开发一种低成本的高场超导体，使6-8特斯拉的临床MRI系统具有成本效益，可用于日常使用。这将有利于需要高分辨率和快速成像的MRI应用。

DESCRIPTION (provided by applicant): The long term objective of this Fast Track Phase I and Phase II is to develop a low cost high field superconductor that can enable cost effective 6-8 tesla clinical MRI systems for every day use. This will benefit the public for MRI applications that require high resolution and rapid imaging. This matches with NIH mission of delivering cost effective improved health care to the public. The specific objectives of this Fast Track Phase I and Phase II proposal is to make significant improvement in the price-performance of MgB2 superconductor wires in the 7-11 tesla range at 4 K. Presently various MRI producers are considering clinical MRIs in the 7 Tesla range. Around the world MRI systems in the 7-9 tesla range have been built for research purposes, at a cost of several million dollars each. Presently an economical superconductor wire does not exist for high volume, low cost, 7-8 tesla MRI systems. Further commercialization of high field MRI's in the 7-8 tesla range would require the wire to be exposed to fields in the 10-11 tesla range. Unfortunately this is outside field range of NbTi superconductors, the workhorse superconductor for the commercial 1.5 and 3.0 tesla (6 tesla on the wire) MRI systems. While Nb3Sn superconductors has improved and operates in these higher fields of 7 to 20 tesla, this wire is still quite expense, 4 to 6 times more expensive on a $ per kilo-amp-meter basis at 7-11 tesla compared to NbTi wire at 6 tesla. Hyper Tech has projected that a MgB2 wire can be close to the same $ per kilo-amp-meter at 7-11 tesla as NbTi at 6 tesla on the wire. This is based on the experimental work of various researchers where Bc2 of over 35 tesla have been obtained, and various thin film research work have produced 1,000,000 A/mm2 current densities at 4.2 K in self field and over 1000 A/mm2 at 10 tesla. If this type of performance can be obtained in bulk wires, then this low price-performance for MgB2 is possible to enable low cost 6-8 tesla clinical MRI Systems. In this Fast Track Phase I and II we intend to accomplish these objectives through improved manufacturing, improved boron powder manufacturing, and improved high temperature insulation. This Fast Track Phase I and Phase II will develop a low cost high field superconductor that will enable cost effective 6-8 tesla clinical MRI systems for every day use. This will benefit the public for MRI applications that require high resolution and rapid imaging.