Influence of Thermal and Magnetic History on Direct Δ<i>T<sub>ad</sub></i> Measurements of Ni<sub>49+x</sub>Mn<sub>36−x</sub>In<sub>15</sub> Heusler Alloys
Luis M. Moreno-Ramírez,
Antonio Delgado-Matarín,
Jia Yan Law,
Victorino FRANCO,
Alejandro Conde,
Anit K. Giri
Affiliations
Luis M. Moreno-Ramírez
Dpto. Física de la Materia Condensada ICMSE-CSIC, Universidad de Sevilla, P.O. Box 1065, 41080 Sevilla, Spain
Antonio Delgado-Matarín
Dpto. Física de la Materia Condensada ICMSE-CSIC, Universidad de Sevilla, P.O. Box 1065, 41080 Sevilla, Spain
Jia Yan Law
Dpto. Física de la Materia Condensada ICMSE-CSIC, Universidad de Sevilla, P.O. Box 1065, 41080 Sevilla, Spain
Victorino FRANCO
Dpto. Física de la Materia Condensada ICMSE-CSIC, Universidad de Sevilla, P.O. Box 1065, 41080 Sevilla, Spain
Alejandro Conde
Dpto. Física de la Materia Condensada ICMSE-CSIC, Universidad de Sevilla, P.O. Box 1065, 41080 Sevilla, Spain
Anit K. Giri
CCDC Army Research Laboratory, Aberdeen Proving Ground, MD 21005, USA
In the present work, using Heusler Ni49+xMn36-xIn15 (with x = 0 and 0.5) alloys, it is shown that the choice of the appropriate measurement protocol (erasing the prior state of the sample in between experiments) in ∆Tad first shot characterization is crucial for obtaining reliable results. Unlike indirect measurements, for which incorrect protocols produce overestimates of the characteristics of the material, erroneous direct measurements underestimate ∆Tad in the region close to its first order phase transition. The error in ∆Tad is found to be dependent on the temperature step used, being up to ~40% underestimation, including a slight shift in its peak temperature.
