ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Pure and mixed aluminium and chromium oxides have been prepared by passage of the halides through a radio-frequency oxidising plasma. The nature of the materials produced has been assessed by electron microscopy, electron diffraction, X-ray diffraction, magnetic susceptibility, and electron spin resonance. The products ware finely divided solids, containing mostly spherical particles in the size ranga 0.01 to 0.15μm; however, the chromia particles were often hexagonal platelets up to 0.4μm in diameter. The X-ray diffraction patterns were well defined, showingδ-alumina andα-chromia as major phases, andθ-alumina as a minor phase. The maximum degree of solid solution of chromium ions in theδ-alumina was limited to about 6% of the total cation content; solid solution of aluminium ions in theα-chromia phase was below the detection limit of 10%. The nature of the particles, the phases produced, and the degree of solid solution are shown to be consistent with a sequence of condensation which can be predicted from thermodynamic data.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00741955
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