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arXiv · 2101.09857

A solution to the permalloy problem

Ananya Renuka Balakrishna·Richard D. James
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Abstract

We propose a solution to the longstanding permalloy problem$-$why the particular composition of permalloy, Fe$_{21.5}$Ni$_{78.5}$, achieves a dramatic drop in hysteresis, while its material constants show no obvious signal of this behavior. We use our recently developed coercivity tool to show that a delicate balance between local instabilities and magnetic material constants are necessary to explain the dramatic drop of hysteresis at 78.5% Ni. Our findings are in agreement with the permalloy experiments and, more broadly, provide theoretical guidance for the discovery of novel low hysteresis magnetic alloys.

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Ananya Renuka Balakrishna, Richard D. James. 2021-01-25. A solution to the permalloy problem. https://arxiv.org/abs/2101.09857

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