Because magnets fabricated using Nd-Fe-B exhibit excellent magnetic properties, this novel material is used in various high-tech industries. However, because of the brittleness and low formability of Nd-Fe-B magnets, the design freedom of shapes for improving the performance is limited based on conventional tooling and postprocessing. Laserpowder bed fusion (L-PBF), the most famous additive manufacturing (AM) technique, has recently emerged as a novel process for producing geometrically complex shapes of Nd-Fe-B parts owing to its high precision and good spatial resolution. However, because of the repeated thermal shock applied to the materials during L-PBF, it is difficult to fabricate a dense Nd-Fe-B magnet. In this study, a high-density (>96%) Nd-Fe-B magnet is successfully fabricated by minimizing the thermal residual stress caused by substrate heating during L-PBF.

In this research, the magnetic abrasive finishing process using (Nd-Fe-B) permanent magnet was applied to confirm the performance and to find the optimum conditions. The STS304 bar was used as the specimen in this experiment. In order to confirm the performance of magnetic abrasive finishing process, the surface roughness (Ra) and diameter reduction were measured when the specimens were processed under the conditions of rotational speeds, frequencies, and magnetic pole shapes. The rotational speeds were varied at 8000rpm, 15000rpm, 20000rpm, and 25000rpm. And the frequencies were changed to 0Hz, 4Hz and 10Hz. Also the shapes of the magnetic pole were changed to flat edge, sharp edge and round edge. It can be concluded that the surface roughness (Ra) and diameter reduction were found to be the best at 25000rpm, 4Hz, flat edge.