GEOMETRY-DRIVEN MAGNETIC FIELD DECAY IN RECTANGULAR PERMANENT MAGNETS
DOI:
https://doi.org/10.59277/RRST-EE.2026.2.11Keywords:
Magnet geometry, Magnetic field decay, Magnetic field distribution, Spatial persistenceAbstract
The behavior of magnetic fields generated by permanent magnets is central to magnetic targeting applications, yet the influence of magnet geometry remains insufficiently characterized experimentally under controlled conditions. In this study, a systematic experimental framework was developed to isolate the effects of thickness and length in rectangular NdFeB magnets using a controlled 2×2 design and central-axis measurements. Field behavior was analyzed using complementary descriptors of local amplification, early axial decay, and spatial persistence, quantified by Ah (z), Dr, and zα, respectively. The results show that thickness primarily enhances near-field intensity, while length governs both spatial field persistence and early decay behavior. These effects are experimentally distinguishable, reflecting distinct geometry-dependent mechanisms. The study establishes a simple, experimentally validated framework for separating geometry-dependent contributions to magnetic field behavior, enabling consistent, physically interpretable comparisons of local amplification, early decay, and spatial persistence in targeting applications.
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