Permanent magnets, particulary magnets Nd-Fe-B, due to their magnetic properties and their
price widely spread around thw world and have therefore replaced other, weaker magnets in
almost all fields.
Research described in this thesis focused on how the particle size of magnetic powder affects
the final properties of a compound and whether the combination of two different sizes of the
same magnetic powder contributes towards better density and magnetic properties of a
compound.
Three different cpompounds were prepared – three materials with the same chemical
composition but with different powder-particle size. First, a premix of magnetic powder and
additive was mixed, then the compound was prepared using extrusion process. Samples
Nd 2 Fe 14 B compound for various measurements were prepared on the injection molding
machine. Several measurements and analysis were carried out: melt flow rate, density
measurements, hysteresis loop measurements and determination of magnetic properties,
performance of 3-point bending test and melt-flow measurement.
Processability of the compound during the manufacturing was observed and measurements
results were compared between each other.
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