TY - NEWS TI - Magnetic and structural characterization of mechanically alloyed Fe_50-Co_50 samples. AU - Pérez Alcázar, Germán A. AU - Zamora, Ligia Edith AU - Marco, José Francisco AU - Romero, Juan José AU - González, Jesús María AU - Palomares, Francisco Javier AB - Samples of nominal composition Fe50Co50 were produced by mechanical alloying by using a planetary ball mill and different milling times. The samples were studied via X-ray diffraction, Mössbauer spectroscopy, and X-ray photoelectron spectroscopy to characterize the phase distribution resulting from the milling process. The Mössbauer data indicated that Co starts diffusing into Fe after 8 h of milling. Between t = 8h and t = 24 h the sample has a heterogeneous composition, presenting a bimodal hyperfine field distribution with maxima centred at 34.3 T and 35.8 - 36.4 T, compatible with the presence of different Fe environments (richer in Co and richer in Fe, respectively). After 48 h of milling, the sample presents a more homogeneous composition showing an almost symmetric hyperfine magnetic field distribution centred at H=34.9 T, indicating that a disordered equiatomic FeCo solid solution has already been formed. The X-ray photoelectron spectroscopy data indicate that the native oxide layer formed on the freshly milled samples contains Co2+, Fe2+ and Fe3+ oxides. After complete removal of this native oxide layer by Ar ion bombardment, X-ray photoelectron spectroscopy analysis yields the composition of the nominal equiatomic Fe50Co50 alloy. DA - 2012-10-04 KW - Magnetic and structural UR - https://bibliotecadigital.univalle.edu.co/handle/10893/3426 ER -