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Title: Magnetic Properties Evaluation of Polyamide 4.6 Bonded Magnetic Composite
Bonded magnetic composites combine the cost-effectiveness, low density, and manufacturing flexibility of conventional polymer binders with the unique magnetic characteristics of magnetic powders/fillers to form multifunctional magneto polymeric composites that offer superior properties to conventional sintered magnets. In this study, a co-rotating twin screw extruder was used to fabricate 20 and 40 wt.% strontium ferrite/polyamide 4.6 bonded magnetic composites viable for fused filament fabrication 3D printing. The characterization conducted on the bonded magnetic composites was scanning electron microscopy, simultaneous differential thermogravimetry, and vibrating sample magnetometry. The microstructure of the bonded composite exhibited a uniform platelet morphology of the strontium ferrite magnetic particles. There was no observable depreciation in the melting transitions, which suggests a thermally resistant magnetic composite. An appreciable increment in % crystallinity of 13 and 20% for 20wt. % and 40wt. % strontium ferrites bonded magnets were observed. This is attributable to the heterogeneous nucleation phenomenon, where the metal powders act as nucleation sites for increased crystalline domains. The bonded composite exhibited significant magnetic anisotropy, with the remanence (Mr), which is the most important property for magnetic application significantly increasing to 49.8% along the easy direction in comparison to the hard axis. This suggests the viability of the fabricated bonded composites in viable in producing anisotropic bonded magnetic devices, which are considered to exhibit stronger magnetic properties.  more » « less
Award ID(s):
2216440
PAR ID:
10539441
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
NA SAMPE
Date Published:
ISBN:
978-1-934551-45-5
Subject(s) / Keyword(s):
Strontium ferrites, Polyamide 4. 6, Bonded Magnet, Twin screw technology, Fused filament fabrication, Materials characterization.
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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