3D transition ferromagnetic metal nano-crystals prepared with gas deposition method (GDM)

The application of gas deposition method (GDM) to the formation of 3d trans ition metal nano-crystals and their structure is reported. A He circulation system was installed in order to purify the inert gas used during the prep aration The metals of Fe, Co, and Ni were evaporated by RF hearing using a ZrO2 linear set in a tungsten crucible and a carbon crucible. X-ray diffrac tion study reveals the same crystal structure as those of bulk states for F e and Ni (bcc and fcc), while the Co nanocrystal has modified structure fro m the fee structure. The averaged grain sizes are ranged about 5 nm. The ma gnetisation are more than 95 % of bulk except for samples with loose packin g, which were prepared with lower pressure difference between the evaporati on and deposition chambers. It is found that oxidisation is remarkably supp ressed during the fabrication process. (C) 1999 Acta Metallurgica Inc.