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对Ｂ_２Ｏ_３－Ｍｇ－Ｃ体系和Ｂ_２Ｏ_３－Ｍｇ体系不同加热速率下的ＤＴＡ曲线进行了分析．发现Ｂ_２Ｏ_３－Ｍｇ－Ｃ体系的自蔓延高温反应中，温度略低于６５０℃时Ｍｇ与Ｂ_２Ｏ_３发生强放热反应，释放出单质 Ｂ；然后中间态 Ｂ与 Ｃ通过固态扩散反应生成 Ｂ_４Ｃ．
The DTA curves of B_2O_3-Mg-C system and B_2O_3-Mg system at different heating rates were analyzed. It is found that in the self-propagating high temperature reaction of B 2 O 3 -Mg-C system, Mg and B 2 O 3 strongly exotherm when the temperature is slightly lower than 650 ° C to release elemental B, and then B_4C is formed by solid state diffusion reaction of B and C.