Stress-induced heating in commercial conductors and its possible influence on magnet performance

Calorimetric measurements show that significant amounts of heat are generated when a multifilamentary composite conductor is stressed in tension to levels expected to occur in large, high-field magnet systems. When the stress on the conductor is repetitively cycled between zero and some maximum value, the amount of heat produced per cycle is constant after the first few cycles. Comparison is made between calorimetric determinations of heat injections and the work done on the specimen as indicated by stress-strain curves. Stress-strain curves for a number of commercial conductors indicate that the most important determinant of the magnitude of this effect is the choice of matrix material.