Improvements in and relating to permanent magnets or other elements possessing permanent magnetism

摘要

In compressing a mixture of metallic powders having different values of coercive force and size to form a permanent magnet, the mould is lined with sheets of material such as soft iron from 2 - 3 tenths m.m. thick to prevent wear. The linings may be removed from the core immediately after moulding or after heat treatment.