Aluminum-nickel-cobalt brake magnets for watt-hour meters

IN 1932 a new aluminum-nickel permanent-magnet material was announced. It may desirably contain a small percentage of cobalt and in that form is commercially available in castings from several dependable suppliers. A typical analysis is aluminum 12 per cent, nickel 20 per cent, cobalt 5 per cent, with the rest iron. As compared with previously available materials, it has such a high coercive force as to affect design radically. No discussion of the material itself will be given as this has been presented elsewhere.^1–3