Evaluation of magnetocaloric behavior and refrigeration performance of Gd3Co10Al87 nanostructured thin film alloy with multiple Curie temperatures

Bayer, Özgür
Baghaei Oskouei, Seyedmohsen
The Gd3Co10Al87 thin film was investigated since it contains a higher atomic rate of aluminum, an inexpensive, recyclable, and abundant material. A thermionic vacuum arc system deposited Gd3Co10Al87 nanostructured thin film, and its surface and magnetic properties were analyzed. Mean grain dimension was measured as 30 nm and 50 nm, with the grain homogeneously distributed according to field emission scanning electron microscopy analyses. The film thickness was measured as 220 nm in cross-section field emission scanning electron microscopy. According to the X-ray diffraction analyses, Gd2O3 and CoO crystal phases were detected. In temperature dependence of the magnetization measurements at 50Oe and 100Oe, double-Curie temperature behaviors were detected approximately at 90 K and 226 K. Refrigeration performance via thermodynamically analyzing an Ericsson refrigeration cycle was studied by taking the Curie temperatures as the cold reservoir temperatures and the hot reservoir temperatures varying 10 K, 15 K, and 20 K higher than Curie temperatures. At the Curie ranges of 90 K and 226 K, COPs of 4.86 and 7.2 were obtained, respectively, at hot reservoir temperatures of 10 K higher than Curie temperature. The Carnot efficiencies for low and high-temperature cycles were 17–52% and 17% and 32%, respectively, declining as the temperature span increases. The suggested cycles show the material’s potential to be utilized in a wide range of applications. Double-Curie approximation is a novel approach capable of opening a new gate for the broad range of magnetocaloric materials due to metal oxide phases.
Applied Physics A: Materials Science and Processing


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Citation Formats
Ö. Bayer, S. Baghaei Oskouei, and S. PAT, “Evaluation of magnetocaloric behavior and refrigeration performance of Gd3Co10Al87 nanostructured thin film alloy with multiple Curie temperatures,” Applied Physics A: Materials Science and Processing, vol. 129, no. 4, pp. 0–0, 2023, Accessed: 00, 2023. [Online]. Available: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85149945964&origin=inward.