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G. Giannopoulos, C. Sarafidis, M. Gjoka, L. Reichel, A. Markou, W. Wallisch, V. Psycharis, J. Fidler, D. Niarchos:
"Rare Earth Free Permanent Magnets";
in: "REPM 2014 - 23 Int. Workshop on Rare Earth and Future Permanent Magnets and Their Applications", University of Delaware, 2014, 388 - 392.

REFREEPERMAG is an EU-funded project to develop a new generation of novel materials without rare earths or platinum for high performance permanent magnets as a replacement of the existing ones mainly based on rare-earths. To achieve this objective our research is based on: a) exploitation of shape anisotropy of high magnetic moment materials produced in the form of nanoparticles (nanowires, nanorods) with high aspect ratio (>5) via chemical environmentally friendly polyol process, which will be then consolidated with novel processes for a new generation of permanent magnets with a maximum energy product (BH)max between 10 and 20 MGOe, and b) using a novel high-throughput thin film synthesis and characterization approach to search for very promising candidate materials of the type (Fe-Co-Mn)-X (X = other 3d or 4d metals and B, C) and/or Heusler alloys with high magnetization, that can be formed in a tetragonal or hexagonal structure by epitaxial growth on selected substrates, under various conditions of pressure, stoichiometry and temperature.
Within the first two years we a) modeled libraries of candidate tetragonal FeCo-X (X = C, B, N, P) phases with large anisotropy, b) produced FeCo-X nanowires with coercivity values in excess of 0.5 T using a polyol process, c) deposited tetragonally distorted FeCo-C films on Au-Cu substrates using sputtering and laser ablation, and d) prepared tetragonally distorted Mn-Fe-Co-Ga phases with attractive magnetic properties. Up scaling and the combinatorial sputtering approach will be heavily employed in the last year of the project towards the final goal, following an integrated approach "Materials by design-fabrication-characterization" for low cost permanent magnets, leading to more efficient energy and power dense devices with positive environmental and socioeconomic impacts.

rare earth free; combinatorial; Heusler alloys; anisotropy