info:eu-repo/semantics/article
Magnetic behavior of twin roller melt spun Cu90 Co10 alloys
Registro en:
Núñez Coavas, Henry; Pozo Lopez, Gabriela del Valle; Fabietti, Luis Maria Rodolfo; Condó, Sergio Alberto; Urreta, Silvia Elena; Magnetic behavior of twin roller melt spun Cu90 Co10 alloys; Institute of Electrical and Electronics Engineers; IEEE Transactions on Magnetics; 49; 8; 8-2013; 4518-4521
0018-9464
1941-0069
CONICET Digital
CONICET
Autor
Núñez Coavas, Henry
Pozo Lopez, Gabriela del Valle
Fabietti, Luis Maria Rodolfo
Condó, Sergio Alberto
Urreta, Silvia Elena
Resumen
Magnetoresistive Cu90 Co10 alloys have been produced by twin roller melt spinning at tangential wheel speeds between 10 m/s and 30 m/s to obtain different solute and Co-rich precipitate distributions. X-ray diffraction indicates that the ribbons are polycrystalline with a fcc Cu(Co) (200) textured matrix; no evidence of a spinodal-like composition modulation could be detected with this technique. Transmission electron microscopy observations performed in samples quenched at 10 m/s indicate the existence of small, coherent, Co-rich precipitates of mean size of about 11 nm and bigger (~40 nm) Co-oxide particles. The small coherent precipitates form colonies inside the grains, mediated by precipitate free zones. Samples quenched at 30 m/s are single magnetic phase (superparamagnetic), but the hysteresis loops of the other as cast ribbons are well fitted by a superparamagnetic contribution and a ferromagnetic one, the latter arising from the Co-rich precipitates. Room temperature coercivities, of about 30-50 mT, are lower than those predicted for a mechanism of coherent rotation in the ensemble of non-interacting, Co-rich precipitates. Fil: Núñez Coavas, Henry. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina Fil: Pozo Lopez, Gabriela del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina Fil: Fabietti, Luis Maria Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina Fil: Condó, Sergio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina Fil: Urreta, Silvia Elena. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina