A tool to predict coercivity in magnetic materials

Magnetic coercivity is often viewed to be lower in alloys with negligible (or zero) values of the anisotropy constant. However, this explains little about dramatic drop FeNi at a non-zero value. Here, we develop theoretical and computational tool investigate fundamental interplay between material constants that govern bulk magnetic alloys. The two distinguishing features our are that: (a) introduce large localized disturbance, such as spike-like domain, provides nucleation barrier for magnetization reversal; (b) account magneto-elastic energy—however small—in addition magnetostatic energy terms. We apply show interactions local instabilities constants, magnetostriction key factors Using model, minimum permalloy composition (Fe21.5Ni78.5) which alloy’s constant not zero. systematically vary around composition, identify new combinations small. More broadly, framework potentially discover novel materials low coercivity.