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Superconducting magnets cooled by cryocooler, without liquid helium, have been developed in recent years. This kind of magnet system is very easy and convenient to operate. The stability of the magnet depends on the balance between the cryocooler refrigeration capacity and the thermal loads. Based on thermal analysis for the magnet, study has been carried out on the stability of cryocooler-cooled superconducting magnet during current excitation.

The application of high magnetic field to material processing, so called electromagnetic processing of material (EPM) has been recognized as cutting edge technology, especially in the field of advanced material processing. It is the most effective methods to control thermal, mass and energy transfer during material solidification. A wide-bore conduction-cooled superconducting magnet with operating current of 116 A was designed, fabricated and tested for the material processing devices. The superconducting magnet has the effective warm hole of 18 cm, the maximum center field of 6 T and homogeneity of 5% in diameter of 5 cm. After the Nb/sub 3/Sn coil insert installed, the magnet can provide the maximum center field of 10 T with effective warm bore of 10 cm. A second-stage GM cryocooler with the second-stage cooling power of 1 W is used to cool the superconducting magnet from room temperature to 4.2 K. In this paper, the design, fabrication, test, stress analysis and quench protection characteristics are presented.