Parts | Days | Selection | Search | Updates | Downloads | Help
MA: Fachverband Magnetismus
MA 67: Poster 4
MA 67.29: Poster
Friday, March 24, 2017, 09:30–13:00, P2-OG3
Direct measurements of Δ T in magnetocaloric and electrocaloric samples utilizing modulated fields at variable frequencies — •Jago Döntgen1, Jörg Rudolph1, Steffen Salomon2, Alfred Ludwig2, Tino Gottschall3, Oliver Gutfleisch3, Anja Waske4, Sylvia Gebhardt5, and Daniel Hägele1 — 1AG Spektroskopie d. kondensierten Materie, Ruhr-Universität Bochum — 2Werkstoffe der Mikrotechnik, Ruhr-Universität Bochum — 3Funktionale Materialien, Technische Universität Darmstadt — 4Institut für komplexe Materialien, IFW Dresden — 5Multifunktionale Werkstoffe und Bauteile, Fraunhofer IKTS Dresden
We present magneto- and electrocaloric data taken by our newly developed non-contact technique for direct measurements of the adiabatic temperature change in modulated fields. High field frequencies allow for magnetocaloric measurements on low volume samples, as demonstrated on a gadolinium film as thin as 1.4 µm. The dynamic behaviour of hydrogenated La-Fe-Si and gadolinium is investigated by applying modulated magnetic fields at varying frequencies up to 1.2 kHz. The experimental setup is further used to measure the electrocaloric effect in the relaxor dielectric PMN-PT, which exhibits a pronounced ageing behaviour both in its dielectric and electrocaloric properties.