Thermo-reversible permanent magnets in the quasi-binary GdCo5-xCux system

TL;DR

This study investigates GdCo5-xCux alloys as thermo-reversible permanent magnets with temperature-dependent magnetization, demonstrating their potential for applications like actuators and temperature sensors.

Contribution

It introduces GdCo5-xCux alloys exhibiting temperature-induced magnetization compensation and demonstrates their use in thermo-reversible magnetic devices.

Findings

Coercive fields up to 1.6 T measured in annealed crystals

Compensation points near room temperature for x=1-2.2

Successful demonstration of actuator and temperature sensor applications

Abstract

Ferrimagnetic GdCo5-xCux alloys exhibiting the effect of Gd- and 3d-sublattice magnetization compensation at defined temperatures were studied with respect to their use as thermo-reversible permanent magnets (PM). Coercive fields 0Hc in the range 0.3 to 1.6 T were measured for annealed single crystals with x = 1 - 2.2 having compensation points in the vicinity of room temperature. Two applications of such a thermo-reversible PM, namely a thermally controlled actuator and a contactless temperature sensor, are demonstrated.