Details

Autor(en) / Beteiligte

• Caron, L.
• Ou, Z.Q.
• Nguyen, T.T.
• Cam Thanh, D.T.
• Tegus, O.
• Brück, E.

Titel

On the determination of the magnetic entropy change in materials with first-order transitions

Ist Teil von

• Journal of magnetism and magnetic materials, 2009-11, Vol.321 (21), p.3559-3566

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2009

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• An accurate method to determine the magnetic entropy change in materials with hysteretic first-order transitions is presented, which is needed to estimate their potential for applications. We have investigated the effect of the maximal entropy change derived from magnetization measurements performed in different measurement processes. The results show that the isothermal entropy change can be derived from the Maxwell relations even for samples with large thermal hysteresis. In the temperature region with hysteresis, overestimating the entropy change can be avoided by measuring the isothermal magnetization of the sample after it is cooled from the paramagnetic state to the measurement temperature. In this way the so-called peak effect is not observed as shown here for a few compounds.