The magnetic and magnetocaloric properties of nanostructured CoMnGe0.95Ga0.05

被引：12

作者：

Yuzuak, E. ^{[1
]}

Durak, G. ^{[1
]}

Dincer, I. ^{[1
]}

Elerman, Y. ^{[1
]}

机构：

[1] Ankara Univ, Dept Engn Phys, Fac Engn, TR-06100 Ankara, Turkey

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2012年 / 541卷

关键词：

Nanopowders; Magnetocaloric effect; Martensitic transition; ALLOY;

D O I：

10.1016/j.jallcom.2012.05.077

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Evolution of magnetocaloric effect (MCE) of nanostructured CoMnGe0.95Ga0.05 powders has been investigated by electron microscopy (SEM), X-ray powder diffraction (XRD), thermal (DSC) and magnetization measurements. The nanostructured powders are composed of very fine grains (7 +/- 2 and 35 +/- 2 nm) obtained from Rietveld refinements. The nanostructured powders show the unique ferromagnetic martensite-paramagnetic austenite transition around the room temperature like the bulk alloy. Furthermore, while the martensitic transition occurs in narrow temperature for bulk alloy, it occurs in broad temperature range for the nanostructured powders. The isothermal magnetic entropy change values -Delta S-M are estimated from the isothermal magnetization curves. The maximum Delta S-M values of 5 h milled nanopowders are -7.2 and -21.5 J kg(-1) K-1 for a magnetic field change of 2 and 7 T, respectively. The magnitudes of the MCE, magnetic and thermal hysteresis values of nanostructured powders are smaller than those of bulk alloy. Our findings offer the nanostructured CoMnGe0.95Ga0.05 powders for the promising applications in magnetic refrigeration. (C) 2012 Elsevier B. V. All rights reserved.

引用

页码：256 / 262

页数：7

共 24 条

[1] CRITERION FOR FERROMAGNETISM FROM OBSERVATIONS OF MAGNETIC ISOTHERMS [J].

ARROTT, A .

PHYSICAL REVIEW, 1957, 108 (06) :1394-1396

[2] Magnetocaloric properties of amorphous GdNiAl obtained by mechanical grinding [J].

Chevalier, B ;

Bobet, JL ;

Marcos, JS ;

Fernandez, JR ;

Sal, JCG .

APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, 2005, 80 (03) :601-606

[3]

Dincer I., J ALLOYS COMPD

[4] Bulk and high-energy ball-milled Gd5Si2Ge2: Comparative study of magnetic and magnetocaloric properties [J].

do Couto, Giselle Giovanna ;

Svitlyk, Volodymyr ;

Jafelicci, Miguel, Jr. ;

Mozharivskyj, Yurij .

SOLID STATE SCIENCES, 2011, 13 (01) :209-215

[5] Large low-field magnetocaloric effect in MnCo0.95Ge1.14 alloy [J].

Fang, Y. K. ;

Yeh, C. C. ;

Chang, C. W. ;

Chang, W. C. ;

Zhu, M. G. ;

Li, W. .

SCRIPTA MATERIALIA, 2007, 57 (06) :453-456

[6] Magnetocaloric materials [J].

Gschneidner, KA ;

Pecharsky, VK .

ANNUAL REVIEW OF MATERIALS SCIENCE, 2000, 30 :387-429

[7] Large magnetic entropy changes in the Ni45.4Mn41.5In13.1 ferromagnetic shape memory alloy [J].

Han, Z. D. ;

Wang, D. H. ;

Zhang, C. L. ;

Tang, S. L. ;

Gu, B. X. ;

Du, Y. W. .

APPLIED PHYSICS LETTERS, 2006, 89 (18)

[8]

Han Z.D., 2006, APPL PHYS LETT, V90

[9] Properties of magnetocaloric La(Fe, Co, Si)13 produced by powder metallurgy [J].

Hansen, Britt Rosendahl ;

Kuhn, L. Theil ;

Bahl, C. R. H. ;

Lundberg, M. ;

Ancona-Torres, C. ;

Katter, M. .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 2010, 322 (21) :3447-3454

[10] DIFFUSIONLESS ORTHORHOMBIC TO HEXAGONAL TRANSITIONS IN TERNARY SILICIDES AND GERMANIDES [J].

JOHNSON, V .

INORGANIC CHEMISTRY, 1975, 14 (05) :1117-1120

← 1 2 3 →