Magnetic Refrigeration with Recycled Permanent Magnets and Free Rare‐Earth Magnetocaloric La–Fe–Si

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.

Exploring thermodynamic characteristics and magnetocaloric effect of an edge-decorated Ising multilayer nanoparticle with graphene-like structure

“…The magnetocaloric effect (MCE) refers to the thermal response of magnetic material to a changing magnetic field under adiabatic condition [41] and has been widely applied in various fields of magnetic refrigeration [42], medical [43] and other fields. Therefore, some researches have been devoted to improving the MCE of the nanoparticles in experiment, such as core-shell nanoparticles [44] and La 0.8 Ca 0.2 MnO 3 nanoparticles [45].…”

How to build the optimal magnet assembly for magnetocaloric cooling: Structural optimization with isogeometric analysis

“…An even higher 𝛬 cool could be achieved here by increasing the air gap. It has therefore been proposed to include 𝐵 4∕3 in such merit figures (Benke et al, 2020).…”

Magnetocaloric properties in (La,R)(Fe,Mn,Si)13H (R = Ce and Pr)—toward a better alloy design that results in a reduction in volume of permanent magnets and the establishment of long-term reliability in cooling systems

“…Presently, in addition to fundamental investigations [3,[11][12][13][14][15][16][17], social implementation prospect must also be addressed for further development. One of the major problems is the heavy weight and high cost of permanent-magnet arrays [9,18], and the spread of the product will end when the focus shifts from this issue [19,20].…”