Consequences of the magnetocaloric effect on magnetometry measurements
| Title | Consequences of the magnetocaloric effect on magnetometry measurements |
| Publication Type | Journal Article |
| Year of Publication | 2010 |
| Authors | Hansen BR, Bahl CRH, Kuhn LT, Smith A, Gschneidner KA, Pecharsky VK |
| Journal Title | Journal of Applied Physics |
| Volume | 108 |
| Pages | 043923 |
| Date Published | 08/15 |
| ISBN Number | 0021-8979 |
| Accession Number | ISI:000281857100096 |
| Keywords | co, gd5si2ge2, la(fe, powder-metallurgy, temperature |
| Abstract | Magnetization curves recorded at high sweep-rates on magnetic materials near a phase transition temperature can be affected by temperature changes in the material due to the magnetocaloric effect. This change in the sample temperature is a result of the quasiadiabatic conditions that can occur under such conditions and we demonstrate its effects on magnetization curves of two magnetocaloric materials, La(Fe0.945Co0.055)(11.9)Si-1.1 and Gd5Si2Ge2. We show how a quantity calculated from isothermal magnetization curves, the magnetic entropy change, Delta S-M, is affected by the erroneous data. As Delta S-M is a measure of the magnetocaloric effect, the discrepancies demonstrated here are more severe close to a peak in Delta S-M, which is precisely the quantity that is of interest and reported on in the literature from possibly erroneous magnetization data. We also demonstrate how, through simple measurements and without a direct measurement of the sample temperature, one can determine an appropriate sweep-rate of the magnetic field. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3466977] |
| URL | <Go to ISI>://000281857100096 |
| DOI | 10.1063/1.3466977 |
