Entity

Time filter

Source Type

Le Touquet – Paris-Plage, France

Romero-Torralva C.,University of Seville | Mayer C.,Erasteel SAS | Franco V.,University of Seville | Conde A.,University of Seville
2015 IEEE International Magnetics Conference, INTERMAG 2015 | Year: 2015

Despite the increasing interest in magnetocaloric materials for their application in magnetic refrigeration devices [1], most of the published studies focus their attention either on the characterization of the magnetic entropy change of the materials, or on the adiabatic temperature change measured at small sweeping rates of the magnetic field, with very scarce results on the frequency dependence of the magnetocaloric response [2]. However, in order to evaluate the applicability of materials in refrigerator devices, it is necessary to know their response in conditions which resemble the actual application. Moreover, materials which might have an outstanding performance at quasistatic rates could be outperformed by other compounds which have a more modest response at low frequencies but keep it steady at higher operating frequencies, as the total cooling capacity of the device is associated to the number of cycles which it can perform per unit time [3]. © 2015 IEEE. Source


Hai X.,CNRS Neel Institute | Hai X.,Erasteel SAS | Mayer C.,Erasteel SAS | Colin C.V.,CNRS Neel Institute | Miraglia S.,CNRS Neel Institute
Journal of Magnetism and Magnetic Materials | Year: 2015

Promising magnetocaloric material La(Fe,Si)13 with a first-order magnetic transition has been widely investigated. The observed instability of hydrogen in the material is detrimental for its industrial upscale and a better control of the hydrogen absorption/desorption is necessary to optimize its application potential. In this article, the hydrogen absorption kinetics is studied through an in-situ neutron diffraction experiment. The results allow us to have an inside look at the structure "breathing" to accommodate the interstitial atoms and compare the effect of hydrides with carbohydrides. © 2015 Elsevier B.V. Source


Hai X.,CNRS Neel Institute | Hai X.,Erasteel SAS | Mayer C.,Erasteel SAS | Colin C.V.,CNRS Neel Institute | Miraglia S.,CNRS Neel Institute
Journal of Magnetism and Magnetic Materials | Year: 2016

Promising magnetocaloric material La(Fe,Si)13 with a first-order magnetic transition has been widely investigated. The observed instability of hydrogen in the material is detrimental for its industrial upscale and a better control of the hydrogen absorption/desorption is necessary to optimize its application potential. In this article, the hydrogen absorption kinetics is studied through an in-situ neutron diffraction experiment. The results allow us to have an inside look at the structure "breathing" to accommodate the interstitial atoms and compare the effect of hydrides with carbohydrides. © 2015 Elsevier B.V. Source


Mayer C.,Erasteel SAS | Dubrez A.,Erasteel SAS | Pierronnet M.,Erasteel SAS | Vikner P.,Erasteel SAS
Physica Status Solidi (C) Current Topics in Solid State Physics | Year: 2014

In this paper, we present a novel process based on gas atomization and powder metallurgy techniques to produce reliable and stable (La1-zCez)(Fe1-x-yMnySix)13Hn materials, with 0.08 ≤ x ≤ 0.15, 0 ≤ y ≤ 0.05, 0 ≤ z ≤ 0.3 and 1.5 ≤ n ≤ 3. With this process, shaped pieces ready-to-use into refrigeration devices can be produced. Gas atomisation is a rapid solidification technique that prevents the La-Fe-Si-type alloy from forming very large α-Fe dendrites during cooling, allowing to easily and efficiently heat treat the obtained powder to form the magnetocaloric NaZn13-type intermetallic. In this process, a batch of 500 kg of alloy was first gas atomized into powder. The powder was then annealed at 1373 K under Ar for one hour to reach around 95% of magnetocaloric phase, and subsequently hydrogenated. Finally, the powder was shaped into composite shaped products containing 91.5 wt.% of powder, by extrusion. This process induces no loss of matter and allows producing non fragile pieces comprising thin portions. Our first results on the stability of partially hydrogenated (La,Ce)(Fe,Mn,Si)13 materials are shown and we discuss on the possible existence of conditions of instability liked to both the composition of the magnetocaloric phase and the level of hydrogenation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Lanzarini J.,CNRS Femto ST Institute | Barriere T.,CNRS Femto ST Institute | Sahli M.,CNRS Femto ST Institute | Gelin J.C.,CNRS Femto ST Institute | And 4 more authors.
Materials and Design | Year: 2015

Magnetic refrigeration is an innovative and promising alternative to traditional refrigeration systems. This technology does not require refrigeration gases and offers a high thermodynamic efficiency, reducing the global environmental impact associated with the process. However, the production of magnetocaloric components used as regenerators in magnetic refrigeration systems is a significant challenge. This work consists of developing an innovative process to obtain magnetocaloric components by powder injection or extrusion moulding. A component containing up to 91.5. wt.% magnetocaloric powder was obtained using a gas atomised magnetocaloric powder La-Fe-Si alloy patented by Erasteel. The powder is first mixed with a thermoplastic polymer to obtain a "ready to shape" feedstock. Then, the feedstock is either injected or extruded to obtain the magnetocaloric component. Characterisations of the thermo-physical and mechanical properties are carried out during all stages of processing, from pure powder to injected parts. A study on the modification of the Curie temperature as a result of dehydrogenation was performed during each processing stages. Good processability was demonstrated for the highly loaded feedstock and conservation of the magnetocaloric properties during the process. Finally, the process does not induce any mass loss and allows the production of stable pieces containing a giant magnetocaloric effect. © 2015 Elsevier Ltd. Source

Discover hidden collaborations