GUTFLEISCH , Oliver

Different excitations, like temperature, magnetic field, or pressure, can drive a martensitic transition in Heusler alloys. Coupled phenomena in these materials lead to interesting magnetocaloric and barocaloric effects ascribed to this transition. In this work, we demonstrate that isothermal transformations induced by a magnetic field and...

In this work, we study the effect of Ni substitution on the magnetocaloric properties of La(Fe,Si)13 compounds. Sample quality has been optimized by a combination of induction melting and suction casting techniques, which allowed to shorten the annealing time by an order of magnitude and expand the existing range of LaFe11.6-xNixSi1.4 phase...

We propose a combination of the Kolmogorov–Johnson–Mehl–Avrami nucleation and growth theory and the Bean–Rodbell model to describe the field-induced transition in LaFe11.6Si1.4 alloys. The approach is applied to a set of bulk samples undergoing first-order transitions produced by different routes and including doping effects. The kinetic...

The ideal magnetocaloric material would lay at the borderline of a first-order and a second-order phase transition. Hence, it is crucial to unambiguously determine the order of phase transitions for both applied magnetocaloric research as well as the characterization of other phase change materials. Although Ehrenfest provided a conceptually...