Abstract
Ultrafine particles (UFP) of Fe-Ni, Fe-Cu and Fe-Si alloys were produced by arc melting, vaporization and deposition of iron alloys in 50%H2-50%Ar atmosphere (“hydrogen plasma-metal” reaction) at 0.1 MPa pressure. The morphology, chemical composition and crystal structure of particles obtained were determined by TEM observation, energy dispersion analysis for X-ray and X-ray powder diffraction.
It was recognized that the chemical composition of Fe-Ni UFP was nearly identical with bulk composition. The composition of Cu in Fe-Cu UFP and Si in Fe-Si UFP remarkably deviated positively and negatively from the bulk composition, respectively. It was found that the deviation tendency of composition between UFP and bulk of alloys can be assessed by using an activity curve of alloys at the high temperature range of above 2000-2500 K.
