ISSN:
1573-9066
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Summary 1. The authors have studied the conditions for obtaining yttrium and gadolinium borides by vacuum-thermal reduction of yttrium and gadolinium oxides by the reaction MeO+2B→MeB+BO. Methods have been developed for obtaining YB4, YB6, GdB4, and GdB6 with chemical and phase compositions close to those required by the formulas 2. When the borides are obtained by this reaction, YB4 and GdB4 are stable in vacuum at all temperatures. Single-phase YB6 and GdB6 are obtained at 1600–1700°. At higher temperatures the hexa-borides decompose, giving tetraborides and boron (which volatilizes). Single-phase YB12 is obtained at 1600–1700°. At higher temperatures it decomposes with formation of YB6 and then YB4. 3. A hypothetical phase diagram of Gd-B is proposed. Data are given on individual properties of phases in the systems Y-B and Gd-B.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00775505
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