A15 phases

The first time that A15 structure was observed was in 1931 when an electrolytically deposited layer of tungsten was examined.

[11] Niobium-germanium held the record for the highest temperature of 23.2 K from 1973 until the discovery of the cuprate superconductors in 1986.

It took time for the method to produce wires from the very brittle A15 phase materials to be established.

[12] Nb3Sn is used for some high field applications, for example high-end MRI scanners and NMR spectrometers.

A relaxed form of the Voronoi diagram of the A15 phase seems to have the least surface area among all the possible partitions of three-dimensional Euclidean space in regions of equal volume.