Kinetics of phase growth in the Cu-Sn system and application to composite Nb/sub 3/Sn strands

Nb/sub 3/Sn is the superconductor most used in the R&D of high field accelerator magnets by either the wind&react or the react&wind technique. In order to program the low temperature steps of the heat treatment, the growth kinetics of Cu-Sn intermetallics was investigated as a function of duration and temperature. The diffusion constants of(eta), (epsilon) and (delta) phases between 150 (degree)C and 550 (degree)C were evaluated using Cu-Sn model samples. For an accurate data analysis, statistical and systematic errors were determined. Next the behavior of Internal Tin and Modified Jelly Roll Nb/sub 3/Sn composites was compared with the model predictions.