Abstract Micron-sized boron carbide (B 4 C) powders were subjected to spark plasma sintering (SPS) under temperature ranging from 1700 °C to 2100 °C for a soaking time of 5, 10 and 20 min and their densification kinetics was determined using a creep deformation model. The densification mechanism was interpreted on the basis of the stress exponent n and the apparent activation energy Q d from Harrenius plots. Results showed that within the temperature range 1700–2000 °C, creep deformation which was controlled by grain-boundary sliding or by interface reaction contributed to the densification mechanism at low effective stress regime ( n = 2, Q d = 459.36 kJ/mol). While at temperature higher than 2000 °C or at high stress regime, the dominant mechanism appears to be the dislocation climb ( n = 6.11).

中文翻译：

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碳化硼粉末放电等离子烧结致密化机制和微观结构演变

摘要 将微米级碳化硼 (B 4 C) 粉末在 1700 °C 至 2100 °C 的温度范围内进行放电等离子烧结 (SPS)，浸泡时间分别为 5、10 和 20 分钟，并使用蠕变变形模型。根据应力指数 n 和来自 Harrenius 图的表观活化能 Q d 解释了致密化机制。结果表明，在1700-2000℃温度范围内，由晶界滑动或界面反应控制的蠕变变形有助于低有效应力状态下的致密化机制（n = 2，Q d = 459.36 kJ/mol） . 而在高于 2000 °C 的温度或高应力状态下，主要机制似乎是位错爬升（ n = 6.11）。