Abstract
A two-step compacting process was developed to achieve the production of high-density Nd-Fe-Co-B/epoxy magnets. Because of its poor compressibility, the severity factor for compaction of Nd-Fe-Co-B magnetic powder reaches a high value of 6.10mm-1 due to its hardness and brittleness. However, by applying the developed method, magnets with a very high density of 6.41Mg/m3 can be fabricated. The second compaction step provides a densification effect on the pre-compacted body obtained in the first compaction step. The densification in the second step occurs through fracturing and stacking of the particles that rose up due to the large spring back during the first compacting and after the removing from the die. This new method enables for fabricated magnets with not only a high density which leads to excellent magnetic properties, but also excellent compressive strength and dimensional accuracy.
