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We have developed a new method of measuring minimum quench energy (MQE) of superconducting wire. There have been conventional methods using heating wires, whose diameters are [approximately]0.1mm and are glued by epoxy resin. When we induce a pulse heat to superconducting wires, a duration of the pulse must be several hundreds micro seconds to demonstrate actual disturbances (for instance wire motion) in a superconducting magnet. In spite of this fact, thermal diffusion time constants of the conventional heaters are larger than the duration of the actual disturbance, because of these electrical insulator of the heating wire and the epoxy bind. Therefore, this kind of heater is not able to demonstrate the actual disturbance. To solve this problem, We have proposed a new constitution of a heater. In our method, heat generation is introduced in high resistive layer on a surface of a superconducting wire. The high resistive layer is consist of carbon paste. The thickness of the carbon paste layer is [approximately]20[[micro]meter], thus a time constant of this heater is expected to be small enough to demonstrate the actual disturbance. Adopting our new method to our MQE measurement, we successfully evaluate MQE of superconducting wires with high precision. Several results are introduced in this paper.

The mechanical properties of multifilamentary [Nb.sup.3]Sn wires have an important role in their application in large scale magnetic systems. The influence of heat treatment schedules and design factors on the mechanical properties of rectangular and round section bronze route wires was investigated. Ultimate tensile strength, yield strength and elongation of stabilized and non-stabilized wires 0.4 mm x 4 mm in section and 0.8 -1.5 mm in dia containing 4000 - 14000 Nb filaments before and after heat treatment were studied. It was shown that a change of the wire design, volume fraction of copper, heat treatment regimes influence strongly on strength and plasticity of wires. The level of the mechanical properties of stabilized wires depends on the volume fraction and location of stabilizer in the section of [Nb.sub.3]Sn wire.

The results of investigation on the influence of the intermediate heat treatment on the mechanical and electrical properties of Cu-Nb alloy microcomposites are presented. The transformation of structure and mechanical properties at the different stages of the production process are discussed. Different designs of microcomposites are developed which allowed to vary the combination of mechanical strength and electroconductivity in sufficiently wide range: UTS - from 900 to 1,200 MPa and conductivity from 65 to 75% IACS. Developed approach to manufacturing process are valid for production of the conductors with enhanced (above 10 mm x 10 mm) cross sections.

We have investigated the giant magnetoimpedance (GMI) effect in fibers of different soft magnetic materials and in Permalloy wires. The fibers have been tested in the radio frequency (rf) range, by measuring the voltage drops in different parts of the circuit. The wires have been tested in the ultra high frequency (uhf) range, by measuring the transmission coefficient [s.sub.21] of coaxial lines having as central conductor a HyMu80 wire. The two methods provided quite similar results showing a strong GMI effect for very different magnetic samples.