Please use this identifier to cite or link to this item:
|Type:||Artigo de periódico|
|Title:||Magnetocaloric effect in GdGeSi compounds measured by the acoustic detection technique: Influence of composition and sample treatment|
da Silva, EC
|Abstract:||In this paper we explore the acoustic detection method applied to the investigation of the magnetocaloric effect in Gd and Gd(5)(Ge(1-x)Si(x))(4) compounds, in the temperature range from 230 to 360 K and for magnetic fields up to 20 kOe. Measurements were performed in as-cast materials, both for powder and pellet samples, and in tree samples with compositions around Gd(5)Ge(2)Si(2) that underwent different thermal treatments. Small differences were observed when comparing powder and pellet samples of Gd and Gd(5)(Ge(1-x)Si(x))(4) compounds with 0.500<x <= 1.00. For the alloys with composition around Gd(5)Ge(2)Si(2), which exhibit giant magnetostriction and coexistence of distinct phases, expressive changes were observed when comparing powder and pellet samples. Based on these cases, it is easy to see that the acoustic method can distinguish a second-order phase transition from a first-order magnetic-crystallographic one, and that it presents good sensitivity to detect spurious material phase in small quantities. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3357375]|
|Editor:||Amer Inst Physics|
|Appears in Collections:||Artigos e Materiais de Revistas Científicas - Unicamp|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.