α-Ti precipitates in high current density multifilamentary Niobium Titanium composites

Abstract

Transmission electron microscopy has been used to characterize the microstructure of a Fermilab composite at various sizes, as well as a variety of commercial composites in their as-delivered, final size state. A much more diverse range of precipitate morphologies than had been previously envisaged was seen. High Jc composites were, however, seen to have a similar morphology of walls of plate like α-Ti in a fine subband structure. The precipitate size ranged from about 0.5 to 200 times the coherence length.