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arXiv · 1712.05820

Unusual effects of manual grinding and subsequent annealing process observed in Gd5.09Ge2.03Si1.88 compound

A. M. G. Carvalho·C. S. Alves·P. V. Trevizoli·A. O. dos Santos·S. Gama·A. A. Coelho
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Abstract

The Gd5.09Ge2.03Si1.88 compound, as well as other magnetocaloric materials, certainly will not be used in their un-manufactured as-cast condition in future magnetic refrigeration applications or other devices. In this work, we have studied the Gd5.09Ge2.03Si1.88 compound processed in different ways, mainly, the as-cast powder, the annealed powder and the pressed and sintered powder. The annealed powder (1370 K / 20 hours) does not present the monoclinic phase and the first-order-magneto-structural transition observed in the as-cast powder. The pressed and sintered powder also do not present the first-order transition. Furthermore, the compacting pressure shifts the second-order-magnetic transition to lower temperatures. The behavior of cell parameters as a function of the compacting pressure indicates that TC is directly affected by parameter c change.

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A. M. G. Carvalho, C. S. Alves, P. V. Trevizoli, A. O. dos Santos, S. Gama, A. A. Coelho. 2018-02-28. Unusual effects of manual grinding and subsequent annealing process observed in Gd5.09Ge2.03Si1.88 compound. https://doi.org/10.1007/s00339-018-1690-6

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