ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Fe100−xCrx ultrafine particles (UFP) with x=5–55 and a size in the range of 100–500 A(ring) have been prepared by the gas evaporation method using Ar gas pressures P=2, 5, and 8 Torr. Transmission electron microscopy with energy dispersive x-ray analysis showed that the composition and structure of the UFPs was the same as in the original bulk alloy. The coercivity Hc at room temperature for the Fe95Cr5, Fe90Cr10, and Fe80Cr20 UFPs reached values up to 1250, 780, and 625 Oe, respectively. The temperature coefficients of these UFPs α(Hc) = −0.09%/°C were much smaller than those of Fe in the temperature range of 20–450 °C when x≤20. A strong antiferromagnetic coupling between Fe and Cr appeared in the small particles. Both the coercivity and saturation magnetization were found to decrease with Cr addition. For samples with x=50%–60%, Hc = 200–300 Oe, and Ms = 30–60 emu/g.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.350100
