The development of a new Iron-cobalt soft magnetic alloy was proposed with a smart combination of both high mechanical strength and moderated iron losses. The former allows higher speed of electric generator, increasing the mass power density. The later improves the thermal transfer of dissipated energies, the sustainability of the generator and help then to a further power density increase. In the complete continuation of Aperam RTD efforts these last years, this new material very recently patented has been demonstrated on laboratory scale and - in some few cases of working features – on industrial tools for small quantities.

But this new material is roughly defined as a new alloys family – Iron-cobalt fully processed (i.e. annealed) and workable material – and it needs to be optimised and fully characterized with respect to working solicitations. In the framework of this project, such a high strength new FeCo alloy was defined in terms of processing parameters corresponding to 800MPa yield stress (R0,2) whereas several metallurgical ways will be studied to get lower iron losses than previous know ones (280W/kg at 2T/400Hz for 0,4mm thickness) without a marked decrease of R0,2. Complementary processes such as thin foils assembly, recovery or texturization will be used to reach this later target, with the help of a specialized partner (LPCES).

After optimisation of the lamination structure and of its microstructure, the new material was deeply characterised mechanically and magnetomechanically (including influence of uni- or bi-axial stresses on the magnetic properties) by another specialized partner (LMT). At the same moment some small quantities (300 to 500kg) of the optimised alloy were processed on industrial tools and punched in pieces to provide 2 rotor stacks to the Topic Manager Company.