Magnetization measurement by use of non-destructive magnet up to 100 Tesla

在第一年，我们指出了两个问题，当一个高磁场磁铁。一个问题是通过环氧树脂使线圈紧密是获得高场所必需的，另一个问题是通过使用马氏体时效钢从外部进行加固增加了电磁线的有效抗拉强度。考虑到这一点，我们可以用直径为20mm的铜线绕制60T的磁场。第二年，我们测试了最大磁场与拉伸强度的关系。因此，我们可以实现在71 T的直径为18毫米，通过改变铜线为铜-银-线。去年，我们检查了71 T-磁铁的可重复性和耐用性，发现磁铁可以产生连续8次69 T的磁场。根据这一结果，我们在液氦温度高达65 T的情况下进行了磁化测量，并在71 T磁体中设置了附加线圈以获得更高的磁场。获得的最大场为77T，直径为13.5mm。根据我们的分析，77T应该分为8T的内线圈和69T的外磁体。这对于外部磁体是无效的。在不能忽略内线圈对外线圈影响的前提下，应采用马氏体时效钢加强内线圈以获得更高的磁场。获得的最大场为80.3T，直径为10.5mm，这是世界纪录。在这种情况下，外部磁体产生71T场，并且该结果可以被认为是有效的情况。根据研究结果，用马氏体时效钢加强每个线圈可以实现100 T磁体，本研究的主题将在不久的将来实现。

In first year, we pointed out two problems when one makes high field magnets. One problem is making coil tight by epoxy resign is necessary to obtain high field and the other is reinforcement by use of maraging steel from outside increases an effective tensile strength of the magnet wire. Taking these points into consideration, we can produce 60T-field with diameter of 20mm by winding Cu-wire.Second year, we tested the tensile sterength dependence of the maximum field. As a result, we can achieve at 71T within a diameter of 18mm by changing Cu-wire into Cu-Ag-wire.The last year, we checked reproducibility and durability of the 71T-magnet and found that the magnet can produce successive 8 shots of 69T-field. Following this result, we carried out magnetization measurement at liquid helium temperature up to 65T.We set an additive coil in the 71T-magnet to obtain higher magnetic field. Obtained maximum field is 77T with 13.5mm diameter. From our analysis, 77T should be separated into 8T of inner coil and 69T of outer magnet. This is not efficient for outer magnet. Supposed that we cannot neglect an effect from inner coil on outer one, we should obtain higher field by reinforcing inner coil with maraging steel. Obtained maximum field is 80.3T with 10.5mm diameter and this is world record. In this case, outer magnet produces 71T-field and this result can be regarded as an efficient case. Following the results, reinforcement of each coil by maraging steel can realizes 100T-magnet and the subject of this study will be attained in very near future.