Ultrafine particles of Fe, Co, and Ni ferromagnetic metals

Autor:	Jinchang Chen, Wei Gong, Z.R. Zhao, Hua Li
Rok vydání:	1991
Předmět:	Magnetization Crystallography Materials science Transmission electron microscopy Ultrafine particle X-ray crystallography Analytical chemistry General Physics and Astronomy Coercivity Inert gas Saturation (magnetic) Amorphous solid
Zdroj:	Journal of Applied Physics. 69:5119-5121
ISSN:	1089-7550 0021-8979
Popis:	Fe, Co, and Ni ultrafine particles (UFP) were prepared by a gas evaporation method in an inert atmosphere. The different preparing conditions of the Fe, Co, and Ni UFP included inert gas pressures and kinds were investigated by means of x‐ray diffraction, transmission electron microscopy (TEM), and magnetic measurements with low or high temperatures. The experimental results show that coercivities Hc of the Fe, Co, and Ni UFP, depending on particle sizes, obey a single‐domain theory. The maximum Hc was 450, 1000, and 1500 Oe, respectively, for Ni (310 A), Fe (210 A), and Co (200 A) at room temperature. The coercivities came up to high in the low temperatures. The saturation magnetizations Ms of the Fe, Co, and Ni UFP decreased with small particle sizes. A face‐centered structure of Co UFP (200–300 A) was confirmed by x‐ray diffraction. Some Fe UFP in the shape of balls (200–400 A) observed in the TEM may be an amorphous structure.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::93e933e11f56418e75c6ed410ab345ff https://doi.org/10.1063/1.348144 Zobrazit plný text záznamu