Binder System Composition on the Rheological and Magnetic Properties of Nd-Fe-B Feedstocks for Metal Injection Molding
Source abstract
Abstract
The applications of Nd-Fe-B-based magnets are experiencing significant diversification to achieve efficiency and miniaturization in different technologies. Metal injection molding (MIM) provides new opportunities to manufacture Nd-Fe-B magnets with high geometrical complexity efficiently. In this study, the impacts of the binder system composition and powder loading on the rheological behavior, contamination, and magnetic properties of the Nd-Fe-B MIM parts were investigated. A high-pressure capillary rheometer was used to measure the apparent viscosity and pressure drops for feedstocks with different binder formulations and powder contents. Also, oxygen and carbon contamination, density, and magnetic properties were measured for different feedstock formulations and powder loadings. From the rheological, density, and magnetic properties points of view, the binder system consisting of 45 vol.% LLDPE as backbone was selected as the optimum formulation. The findings indicated that the sample with this binder system and 55 vol.% powder content had a high density (6.83 g/cm3), remanence (0.591 T), and coercivity (744.6 kA/m) compared to other binder compositions. By using 58 vol.% powder loading, the values of density (7.54 g/cm3), remanence (0.618 T), and carbon residue (982 ppm) improved, and a suitable rheological behavior was still observed. Thus, a suitable feedstock formulation was developed.
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Research context
OpenAlex topics: Magnetic Properties of Alloys · Powder Metallurgy Techniques and Materials · Metallurgical and Alloy Processes
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Institute of Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
CEA-Liten, Université Grenoble Alpes, F-38000 Grenoble, France
Functional Polymers Research Unit, Luxembourg Institute of Science and Technology (LIST), L-4940 Hautcharage, Luxembourg
Industrial Liaison Department, Montanuniversitaet Leoben, 8700 Leoben, Austria
Funding
European Institute of Innovation and Technology (EIT)
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