Magnetocaloric effect

The magnetocaloric effect is measured directly by a differential copper – constantan thermocouple, having one junction “sandwiched” within the sample, and another one fixed nearby, and exposed to the same conditions as the sample [1].

Magnetocaloric effect - temperature range ©Copyright: Dr. Gottschall, Tino

Foto: Tino Gottschall

Download

The sample is fixed by using GE varnish. The holder is surrounded by a heater.

The temperature range with the current thermocouples is 80 – 360 K. The technique is best suited for magnets A, B, and E.

Magnetocaloric effect - measurement example ©Copyright: Dr. Gottschall, Tino

Foto: Tino Gottschall

Download

(a) Mangetocaloric effect of a Ni-Mn-In Heusler alloy showing time-dependent effect at the first-order transition [3].

(b) The maximum ∆Tad obtained in pulsed magnetic fields compared to other measurement devices from elsewhere.

[1] T. Gottschall et al., Phys. Rev. B 99, 134429 (2019)

[2] C. Salazar Mejia, Appl. Phys. Lett. 110, 071901 (2017)