Method of making permanent magnets

Method of producing a permanent magnet body, comprising the steps of:

• a. producing anisotropic first ferromagnetic permanent magnet material by sintering particles of starting material suitable for making permanent magnets at a preselected optimum temperature;
• b. terminating said heating when said sintered magnet material has reached full remanence;
• c. grinding said sintered first ferromagnetic permanent magnet material to a powder, the particles of said ground powder having the following characteristics:
• 1. coercivity .sub.J H.sub.C below the maximum obtainable value for said particles and at least equal to the remanence of the finally produced magnet body;
• 2. remanence 4.pi.J.sub.R between 1.2 and 1.6 times the remanence B.sub.R of the finally produced magnet body, and;
• 3. a fullness factor ##EQU5## of at least 0.6;
• d. mixing said powder particles with a curable nonmagnetic binder;
• e. compacting said powder particles and binder under pressure and under the influence of a magnetic field in a machine to form the shape and size of the final magnet body:
• f. removing said shaped and compacted body from the forming machine, and;
• g. heating said compacted magnet body at a temperature and for a period of time to cure the binder but insufficient to significantly change the dimensions of said body.