Solid solution phases boron carbide

A calculated isothermal section for the Si-B-C system at T = 1400 K was presented by Goujard et al. (1994) [75, 76]. The data were derived from JANAF [140] and assessments of the phases SiBi4, SiBg, SiB3 and the solid solution phase boron carbide. The isothermal section calculated using the data of Kasper (1996) [33] (Fig. 10b) deviates significantly. Experimental investigations at these temperatures suffer from slow reaction kinetics and decisions... 

Boron carbide is rhombohedral (a = 5.163 A a = 65.59°). The stoichiometric composition of boron carbide is Bi3C2(B6.5C), so that B4C is a carbon-saturated solid solution. The phase diagram for the B-C system is shown in Figure 1. The density as a function of stoichiometry is shown in Figure 2. 

Reviews are concerned with structures, properties, preparations ° and applications.The boron carbide phase is a complex solid solution." ... 

J Conard, M Bouchacourt, T Thevenot, G Hermaim. C and "B nuclear magnetic resonance investigations in the boron carbide phase homogeneity range A model of solid solution. J Less Common Met 117 51, 1986. 

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