A Co-Gd-Sm Permanent Magnet with A Zero Temperature Coefficient of Magnetization

The magnetic properties of Co5(GdxSm1−x) alloys were studied as a function of Gd content over the temperature range −200° to + 225°C. From this study it has been determined that alloys with x ≈0.42 have an essentially zero reversible temperature coefficient of magnetization. One alloy with x = 0.425 had a reversible temperature coefficient of +0.0015% per °C over the range 0° to 100°C, and the following magnetic properties: Br 6.35 kGauss, Hc=5.67 kOe, and (BH)max 9.3 MGOe.