Magnetocaloric properties and critical behavior of high relative cooling power FeNiB nanoparticles

Journal Article · Tue Oct 28 04:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4900736· OSTI ID:22308172

Chaudhary, V. ^[1]; Maheswar Repaka, D. V.; Chaturvedi, A.; Sridhar, I. ^[2]

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1. Interdisciplinary Graduate School, Nanyang Technological University, Singapore 639798 (Singapore)
2. School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

Low cost magnetocaloric nanomaterials have attracted considerable attention for energy efficient applications. We report a very high relative cooling power (RCP) in a study of the magnetocaloric effect in quenched FeNiB nanoparticles. RCP increases from 89.8 to 640 J kg{sup −1} for a field change of 1 and 5 T, respectively, these values are the largest for rare earth free iron based magnetocaloric nanomaterials. To investigate the magnetocaloric behavior around the Curie temperature (T{sub C}), the critical behavior of these quenched nanoparticles was studied. Detailed analysis of the magnetic phase transition using the modified Arrott plot, Kouvel-Fisher method, and critical isotherm plots yields critical exponents of β = 0.364, γ = 1.319, δ = 4.623, and α = −0.055, which are close to the theoretical exponents obtained from the 3D-Heisenberg model. Our results indicate that these FeNiB nanoparticles are potential candidates for magnetocaloric fluid based heat pumps and low grade waste heat recovery.

• OSTI ID: 22308172
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 16 Vol. 116; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
BORON COMPLEXES
COOLING
CURIE POINT
FLUIDS
HEAT PUMPS
HEISENBERG MODEL
IRON COMPOUNDS
ISOTHERMS
MAGNETIC PROPERTIES
NANOMATERIALS
NANOPARTICLES
NANOSTRUCTURES
PHASE TRANSFORMATIONS
RARE EARTHS