Magnetic Refrigeration with Recycled Permanent Magnets and Free Rare‐Earth Magnetocaloric La–Fe–Si. Issue 7 (5th June 2020)

• Record Type: Journal Article
• Authors: Benke, Dimitri; Fries, Maximilian; Specht, Marius; Wortmann, Jonas; Pabst, Marc; Gottschall, Tino; Radulov, Iliya; Skokov, Konstantin; Bevan, Alex Ivor; Prosperi, Davide; Tudor, Catalina Oana; Afiuny, Peter; Zakotnik, Miha; Gutfleisch, Oliver
• Is Part Of: Energy technology. Volume 8:Issue 7(2020:Jul.)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-06-05
• Subjects: active magnetic regenerators -- Halbach arrays -- magnet recycling -- magnetic cooling -- magnetocaloric materials; Energy development -- Periodicals; Power resources -- Periodicals; 333.79
• DOI: 10.1002/ente.201901025
• Languages: English
• ISSNs: 2194-4288

Abstract

Abstract : Magnetic refrigeration is an upcoming technology that could be an alternative to the more than 100‐year‐old conventional gas–vapor compression cooling. Magnetic refrigeration might answer some of the global challenges linked with the increasing demands for readily available cooling in almost every region of the world and the global‐warming potential of conventional refrigerants. Important issues to be solved are, for example, the required mass and the ecological footprint of the rare‐earth permanent magnets and the magnetocaloric material, which are key parts of the magnetic cooling device. The majority of existing demonstrators use Nd–Fe–B permanent magnets, which account for more than 50% of the ecological footprint, and Gd, which is a critical raw material. This work shows a solution to these problems by demonstrating the world's first magnetocaloric demonstrator that uses recycled Nd–Fe–B magnets as the magnetic field source, and, as a Gd replacement material, La–Fe–Mn–Si for the magnetocaloric heat exchanger. These solutions show that it is possible to reduce the ecological footprint of magnetic cooling devices and provides magnetic cooling as a green solid‐state technology that has the potential to satisfy the rapidly growing global demands. Abstract : A magnetic cooling device with recycled Nd–Fe–B magnets and the "free rare‐earth" magnetocaloric material La–Fe–Si is used to prove that green magnetic cooling is possible. The recycled magnets provide a magnetic field of up to 1.15 T and a temperature span of 25 K is achieved with a five‐stage active magnetic regenerator made from La–Fe–Si.