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The Dyneema fiber reinforced plastic (DFRP) that has a high thermal conduction property is used as a heat drain material for conduction cooled magnet. The experiments conducted on DFRP indicate that the effects depend on the fiber directions in the plastic.

The study is conducted to discuss a technique in order to reduce mechanical losses under AC operation by use of Zylon fiber reinforced plastic (ZFRP) bobbin in superconducting coils. The test results indicate that the coils whose winding tension at cryogenic temperature are strong make the reduction of mechanical losses possible.

A study is conducted to examine the influence of mechanical losses in AC superconducting coils having composite materials reinforced with Dyneema and glass fibers. The effect of the reduction of the mechanical losses in the coils having the DGFRP bobbins and the comparison with the coils whose bobbins are the DFRP and the GFRP are presented.

It is shown that plastics with high thermal conductivity can be used as spacers in conduction-cooled HTS coils.

Frictional losses caused by the periodic vibration of superconducting wires in AC superconducting coils are investigated and discussed.

Frictional properties are investigated, using an experimental simulation, to determine mechanical losses occurring in AC superconducting coils.

Coils that use Dyneema fiber reinforced plastic (DFRP) bobbin and stainless steel (SUS) bobbin are configured , and induced voltages between the ends of the coils are measured in a backup magnetic field. The coil with SUS bobbin showed sharp peaks in tap voltage induced by quick wire motions, but those using DFRP bobbin showed only a few small peaks, suggesting that motions were constrained by DFRP bobbin.

Two types of superconducting coils having the same specifications have been developed. One of the coils was manufactured from Dyneema fiber reinforced plastic bobbins that expands during the cooling process from room temperature levels to liquid helium temperature levels. The other coil is made of glass fiber reinforced plastic bobbins that contract during the same cooling process. A study of the effect of quench currents on the behavior of the materials has been conducted.

The fabrication of cable-in-conduit conductors (CICCs) with two kinds of nonmetallic conduit materials and the mechanical losses are measured. The results show that the losses decrease with the decrease of the void ratios in the cable-in-conduit conductors.