2015/05/11 by Ana L. Pires, J.H. Belo, Pires, A L +17
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci) #Rare-earth and actinide compounds #Shape Memory Alloy Transformations
paper · pdf · doi:10.48550/arxiv.1505.02575
openalex publication_date 2015/05/11 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
In the lifetime of a magnetic refrigerator the materials are subjected to millions of thermal magnetic cycles, so it is of the utmost importance to predict the behavior of such materials when subjected to related work conditions. Thus, in this work we investigated the influence of thermal cycling in the microstructure, magnetic phase transition and magnetic entropy change of a Gd5Si1.3Ge2.7 thin film up to 1000 cycles. In a first stage, till 450 cycles, the hysteresis area of the magnetization curves as a function of temperature was found to decrease 16% with thermal cycling, due to an arresting of the O(II) phase caused by internal strain. Nonetheless, after 1000 cycles there is a clear loss of the magneto-structural transition. For all thermal cycles the O(I) phase remains unchanged. Therefore, prolonged thermal cycling leads to a strong reduction of the O(II) phase, attributed to an internal pressure build-up, caused by the large number of expansion/compression cycles that the O(II) phase undergoes across the magnetostructural transition.