The structure of Ni-Co-Al-Ti-Cu-Fe permanent magnets

A technique has been developed for extracting one of the phases present in Ni-Co-Al-Ti-Cu-Fe permanent magnet alloys heat-treated to give optimum magnetic properties. Examination of such extracts by electron microscopy and electron-probe microanalysis has confirmed previously held theories that the precipitate is strongly magnetic (50 percent Fe and 50 percent Co) in a virtually nonmagnetic matrix. The results show that for permanent magnets containing 5-percent Ti the matrix has the same structure (
L2_{1}
) as a range of materials known as Heusler alloys.