Development of compact magnet for high magnetic force

Abstract

A high magnetic force is useful for levitating diamagnetic or magnetic materials. The magnetic force is proportional to the product of B and dB/dz. Here the product is called the magnetic force Held. Normally, a high magnetic force field is available only with 20 T class magnets in a few, high-field magnet facilities worldwide. We therefore anticipate realizing zero gravity relatively easily with a compact high force field magnet at any laboratory. What we have designed has enabled us to achieve a magnetic force field of up to 1400 T/sup 2//m at 13 T with a warm bore diameter of 32 mm. To verify that the design works, we successfully fabricated a model magnet using the same electromagnetic force for the design. On the test, the winding behavior was also clearly measured with an optical displacement method. The results indicate that the design is appropriate for such compact, high magnetic force as that applied to water levitation.