Regensburg 2016 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MM: Fachverband Metall- und Materialphysik
MM 24: Topical session: Caloric Effects in ferroic materials II - Methods and Applications
MM 24.2: Vortrag
Dienstag, 8. März 2016, 12:15–12:30, H53
In-situ XRD and 3D imaging techniques for the study of magnetocaloric materials — •Anja Waske1,2, Alexander Funk1,2, Kai Sellschopp1,2, Alexander Rack3, and Sebastian Fähler1,2 — 1IFW Dresden, Helmholtzstraße 20, 01069 Dresden, Germany — 2Institute for Materials Science, TU Dresden, Helmholtzstraße 7, 01069 Dresden, Germany — 3ID 19, ESRF, 6 rue Jules Horowitz, 38043 Grenoble Cedex, France
In magnetocaloric La(Fe,Si)13, an isostructural first-order transition connected with a volume change of around 1.5 vol.% occurs at the critical temperature Tt. We use in-situ computed tomography and situ X-ray diffraction to study this magnetovolume transition as a function of temperature. The experiments have been carried out at the beamline ID 19 at the ESRF in Grenoble (tomography) and the Petra III /2.1 beamline at DESY in Hamburg, respectively. We show that i) by 3D imaging it is possible to track the magnetovolume transition, ii) nucleation and growth of the ferromagnetic phase depends strongly on surface morphology and iii) the virgin effect in magnetocaloric La(Fe,Si)13 is connected to the formation of cracks [1]. These findings connect microstructural aspects of the first-order transition to important properties like hysteresis and kinetics of the phase transition and can therefore help to tailor magnetocaloric materials towards application. Funded by DFG through SPP 1599 www.FerroicCooling.de. [1] A. Waske et al., PSS-RRL 9 (2) 136-140 (2015)