Additive Manufacturing of Bonded Nd-Fe-B-Effect of Process Parameters on Magnetic Properties

作者：Baldissera A B^*; Pavez P; Wendhausen P A P; Ahrens C H; Mascheroni J M

来源：IEEE Transactions on Magnetics, 2017, 53(11): 2101704.

DOI：10.1109/TMAG.2017.2715722

• Additive manufacturing (AM)
• bonded magnets
• isotropic magnets
• powder bed fusion

Isotropic-bonded magnets were fabricated by powder bed fusion additive manufacturing (AM) using a feedstock composed of polymeric binder polyamide 12 (PA-12) and a near stoichiometric Nd2Fe14B atomized nanocrystalline powder. The AM equipment constructed for that purpose uses a computer-controlled laser beam to melt the binder and build the parts layer by layer. Three process parameters were evaluated: layer thickness (LT), hatch spacing (HS), and laser power (LP). For the evaluation of magnetic properties, cylindrical samples with diameter and height of 10 mm were produced and measured in a hysteresisgraph. For a feedstock, based on a 34% volumetric fraction of PA-12, the highest density value achieved was 3.6 g/cm(3), resulting in a remanence of 0.3 T. These relatively low values for remanence are due to the isotropic characteristic of the powder, the binder fraction, and the interparticle porosity not being completely eliminated. Results indicate that LT affects densification more significantly than LP and HS. Consequently, remanence follows the same trend. Coercivity has not been affected much by optimized process parameters, since the values of original atomized powder of around 700 kA/m remained practically the same. The overall conclusion shows encouraging results to explore this alternative AM technique to produce net shape permanent magnets.

• 出版日期2017-11