The superconducting behavior of Nb-65 wt. %Ti and their ternary alloys with 1 wt. % Mo, Re, Si, Ta, V, and Zr was studied with regard to precipitation. Transmission electron microscopy studies were carried out to determine the size and distribution of the precipitates. In contrast to the commerical Nb-Ti superconductor the alloys show a quadratic dependence of the pinning force on the field close to the upper critical field. With a suitable precipitate size distribution but without workhardening these alloys display high current densities which are comparable with commercial Nb-Ti.

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Increased use of composites in aerospace and defense application induces the search for heat resistant material. In present study silica reinforced epoxy functionally graded material using quartz fabric is prepared with different thickness. The gradation in silica : epoxy matrix is maintained with one side pure epoxy to opposite side pure silica. Thermal and mechanical behaviour of the composites were studied. It was found that the temperature gradient of 350°C to 950°C could be maintained for 2 to 5 min if the thickness of insulating silica layer is increased from 0.5 mm to 16 mm. Mechanical properties such as flexural modulus and strength of FGM composites were also evaluated. Strength and modulus decreased with increase of insulating layer.

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