Hitachi, Ltd.

Koo Honjo

Masao Suzuki

Toru Koyama

Akio Takahashi

Akio Mukoh

Keiji Fukushi

Seiji Numata

Shunichi Numata

Shigeo Amagi

Morimichi Umino

Yasuhiro Mizuno

A superconducting magnet coil, an insulating layer, and a superconducting magnet which do not generate quenching under cooled and operational conditions are provided by using a fixing resin capable of suppressing microcrack generation in a resin layer which causes quenching. A superconducting magnet coil manufactured by winding a superconducting wire and fixing the wire with resin and a method for manufacturing thereof, wherein said resin is a low cooling restricted thermal stress and high toughness fixing resin having a release rate of elastic energy G.sub.IC at 4.2 K. of at least 250 J.multidot.m.sup.-2, and/or a stress intensity factor K.sub.IC of at least 1.5 MPa.multidot..sqroot.m, and/or a stress safety factor at 4.2 K. of at least 3, and an allowable defect size at least of 0.3 mm. The superconducting magnet coil manufactured in accordance with the present invention does not cause quenching because microcracks are not generated in said resin when the coil is cooled to the liquid helium temperature, i.e. 4.2 K., and under an operational condition.

Superconducting magnet superconducting magnet coil, and manufacturing

A superconducting magnet coil is produced by winding a superconducting wire to form a coil; impregnating the coil with a curable resin composition of low viscosity which contains for example at least one epoxy resin selected from the group consisting of diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F and diglycidyl ether of bisphenol AF, all having a number-average molecular weight of 350-1,000, a flexibilizer and a curing catalyst, to obtain a curable-resin composition-impregnated coil; and heating the curable-resin-composition-impregnated coil to cure the composition.

Method for producing a superconducting magnet coil

A superconducting magnet coil contains a coil of superconducting wire and a cured product of a curable resin composition with which the coil has been impregnated, the cured product having a thermal shrinkage factor of 1.5-0.3%, preferably 1.0-0.3%, when cooled from the glass transition temperature to 4.2K, a bend-breaking strain of 2.9-3.9%, preferably 3.2-3.9%, at 4.2K and a modulus of 500-1,000 kg/mm.sup.2 at 4.2K, or undergoing a thermal stress of 0-10 kg/mm.sup.2 when cooled from the glass transition temperature to 4.2K and resisting to quench during superconducting operation. It is produced by winding a superconducting wire to form a coil; impregnating the coil with a curable resin composition of low viscosity which contains for example at least one epoxy resin selected from the group consisting of diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F and diglycidyl ether of bisphenol AF, all having a number-average molecular weight of 350-1,000, a flexibilizer and a curing catalyst, to obtain a curable-resin composition-impregnated coil; and heating the curable-resin-composition-impregnated coil to cure the composition.

Superconducting magnet coil and curable resin composition used therein

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Ibaraki, Japan

Koo Honjo