Cast Alnico magnets which are aluminum nickel-cobalt-iron alloys are the most established and widely used permanent magnet materials. Because of their high flux density and superior temperature stability, cast magnets have been accepted in the widest range of application.

Alnico material are manufactured through either a casting or sintering process. Alnico is very hard and brittle. Machining or drilling can not therefore be accomplished by ordinary methods. Holes are usually cored in at the foundry. Magnets are cast or sintered as closely as possible to required sized so that abrasive grinding to finish dimensions and tolerances is minimized.

Specialized casting techniques used to achieve the unique crystalline grain orientation found in the alnico 5 and 8 grades. These anisotropic grades are designed to produce high magnetic output in a specified direction. Orientation is achieved during heat treatment, by cooling the casting from 2000 F at a controlled rate within a magnetic field which conforms to the preferred direction of magnetization. Alnico 5 and Alnico 8 are anisotropic and exhibit a preferred direction of orientation. Magnetic orientation should be specified on your drawing when you send an order to us.

Cast Alnico 5 is the most commonly used of all the cast Alnico's. It combines high indications with a high energy product of 5 MGOe or more and is used extensively in rotation machinery, communications, meters and instruments, sensing devices and holding applications.

The higher resistance to demagnetization (coercive force) of Alnico 8, cobalt content to 35%, allows this material to function well for short lengths or for length to diameter ratios of less than 2 to 1.

Typical Applications for Alnico magnet:

Catalogue of Cast AlNiCo.