A core–shell phenomenon maintain the magnetocaloric properties of the ternary silicide Gd6Co1.67Si3 during water flux ageing

Abstract

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A successful process to prevent corrosion of rich Gd-based room temperature magnetocaloric material during ageing

“…Remarkably unaltered bulk magnetocaloric effect was shown suggesting a passivation action of the top layer containing the paramagnetic Gd2O3 oxide [14].…”

“…Having all this in mind, DI H2O was first chosen to study its direct surface effect on our Gd6Co1.67Si3 material showing moderate room temperature magnetocaloric properties [13]. A core-shell phenomenon at the surface of this ternary silicide when water flux ageing acts for 3 months was recently underlined resulting in a chemical selective corrosion process [14].…”

Microstructural Anisotropy of Magnetocaloric Gadolinium Cylinders: Effect on the Mechanical Properties of the Material

“…A study of the literature shows that gadolinium (Gd) metal and its alloys are widely accepted as the reference material in magnetocaloric refrigeration systems [1,2,3,4,5,6,7,8,9]. Among alternative cooling and near-room temperature refrigeration technologies, magnetic refrigeration has the highest level of current research activity, and is considered to hold some, but not imminent, promise for implementation as better magnetocaloric materials and other technical breakthroughs are needed to realize this promise [10,11,12,13,14,15]. …”

“…With a decrease in the grain size from the micrometer to the nanometer range, (i) the Curie temperature decreased and exhibited a broader shape in DSC (Differential Scanning Calorimetry) heating curves [ 23 ] (ii) the room-temperature electrical resistivity was found to increase, while the low-temperature resistivity increased remarkably [ 24 ]. The oxidized surface layer of a ternary Gd alloy was not found to significantly affect the bulk magnetocaloric performance of the material [ 12 ].…”

The impact of disorder on magnetocaloric properties in Ti-doped manganites of La0.7Sr0.25Na0.05Mn(1−x)TixO3 (0≤x≤0.2)

“…This technique is based on the magnetocaloric effect (MCE) [1][2][3][4] which is an intrinsic property of certain magnetic materials such as manganites considered as famous class of functional materials [5,6]. This effect manifests as temperature change associated to a sudden variation in the applied magnetic field.…”