A new measurement and treatment for kinetics of isothermal oxidation of Si3N4
A new measurement and treatment for kinetics of isothermal oxidation of Si3N4
复制标题
DOI：
10.1016/j.jallcom.2007.04.255
复制
发表时间：
2008-07
影响因子：
6.2
通讯作者：
X. Hou;K. Chou;Xiaojun Hu;Hailei Zhao
中科院分区：
文献类型：
--
作者：
X. Hou;K. Chou;Xiaojun Hu;Hailei Zhao
用热重法研究了α-Si_3N_4粉末在1373 ~ 1573 K温度范围内的氧化动力学。结果表明，氧化产物主要为晶态SiO2，氧化反应主要受扩散控制。在实验数据的基础上，采用新的模型预测了α-Si_3N_4粉末的等温氧化过程，给出了氧化增重随时间和温度变化的解析表达式。实验数据与理论计算结果的比较表明，该模型具有较好的预测效果。在此基础上计算出α-Si_3N_4的氧化活化能为325.6kJ/mol。
The kinetics of the oxidation of α-Si3N4powder has been investigated in the temperature range from 1373 to 1573K experimentally in the air by using thermogravimetry. The results show that the major oxidation product was crystalline SiO2and the oxidation reaction was mainly diffusion-controlled. Based on the experiment data, the new model for predicting the isothermal oxidation process of α-Si3N4powder has been used, which offers an analytic form expressing the oxidation weight gain as a function of time and temperature explicitly. The comparison between experimental data and theoretical calculation shows that this new model works very well. Based on our model the activation energy for the oxidation of α-Si3N4has been calculated to be 325.6kJ/mol.