Magnetic and magnetocaloric properties of Er-Co-Al thin-film alloys

Miri Kim, Jong Woo Kim, Sang Ho Lim

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Er-Co-Al thin films with the compositions of ErCo1.52Al0.36, ErCo1.69Al0.76, and ErCo1.87Al0.16 were fabricated by magnetron-sputtering, and their magnetic and magnetocaloric properties were characterized in the asdeposited state and post-annealed state at 1073 K. The X-ray diffraction results indicate that the microstructure in the as-deposited state consists of an amorphous phase, which then transforms into a cubic Laves phase with C15 symmetry on annealing. The phase transformation, however, is incomplete, evidenced by the existence of Co precipitates and some oxides of Er and Al in the annealed samples. A compensation-like behavior is observed in the as-deposited samples, probably due to the sperimagnetic structure, but it disappears after annealing. The magnetic entropy change is largest for the annealed ErCo1.87Al0.16 sample, in which the composition is closest to the pseudo-binary Er(Co,Al)2 compound. The observed value, however, is rather small (3.2 J/kg K in a field sweep of 0–50 kOe), due the incomplete phase transformation from the amorphous to the cubic Laves phase during annealing.

Original languageEnglish
Pages (from-to)1101-1107
Number of pages7
JournalMetals and Materials International
Volume21
Issue number6
DOIs
Publication statusPublished - 2015 Nov 1

Fingerprint

Laves phases
Annealing
magnetic properties
Thin films
annealing
phase transformations
thin films
Phase transitions
Chemical analysis
Magnetron sputtering
Oxides
Precipitates
precipitates
magnetron sputtering
Entropy
entropy
X ray diffraction
microstructure
Microstructure
oxides

Keywords

  • magnetic materials
  • magnetic properties
  • magnetocaloric effects
  • sputtering
  • X-ray diffraction

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Metals and Alloys
  • Mechanics of Materials
  • Materials Chemistry

Cite this

Magnetic and magnetocaloric properties of Er-Co-Al thin-film alloys. / Kim, Miri; Kim, Jong Woo; Lim, Sang Ho.

In: Metals and Materials International, Vol. 21, No. 6, 01.11.2015, p. 1101-1107.

Research output: Contribution to journalArticle

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