Temperature dependent properties of an anisotropic Mn-Al-C permanent magnet

Abstract

The anisotropy field, coercivity and saturation magnetization in a Mn‐Al‐C permanent magnet were measured as a function of temperature from 4.2K to 300K. The coercivities in both the easy and hard directions were found to decrease linearly with temperature with slightly different slopes. The coercivities measured with the applied field along the hard direction were found to exceed those obtained when the field was aligned with the easy axis. A model for the mechanism producing this effect is discussed. The anisotropy field is found to decrease linearly with temperature while the reduced saturation magnetization follows a −T^3/2 law.