Ferromagnetic Memory-Effect in Ni 52%–Fe Alloy Bars

If one operates the magnetization cycle: saturation magnetization in one direction→magnetic field zero→saturation magnetization in the opposite direction→magnetic field zero→saturation magnetization in the first stage direction→etc. continuously on a Ni 52%-Fe alloy bar, the coercive force in the ascending branch is always found to be larger than the coercive force in the descending branch. This is interpreted to be due to ferromagnetic memory-effect, because the first stage direction of saturation magnetization is memorized. Severe cold drawing of the bar tends to obscure the memory-effect.