摘要
本文采用氧化后再氧化的实验方法,通过对纳米Si3N4陶瓷试样氧化行为的研究和氧化动力学的分析,讨论了纳米Si_3N_4陶瓷的氧化机理。结果表明,Si_3N_4陶瓷的氧化行为表现为氧化增量随时间的变化服从抛物线规律:(ΔW)2=Kpt。提出了氧在氧化层中的向内扩散是Si_3N_4氧化过程中的控制步骤;得出烧结添加剂或杂质对Si_3N_4陶瓷氧化速度的影响,是由于改变了氧化层的组成、结构,使氧在氧化层中的扩散速度发生了变化的结论。
The oxidation mechanism of nano Si3N4 ceramics was discussed by studing oxidation behavior and oxidation kinetics of nano Si^4ceramics samples as well as by reoxidation experiment. The results showed that the oxidation weight gains of Si3N4 followed parabolic law （ △W）2=Kpt as the time increased. Oxygen diffusion from outside surface to inside of oxidation layer was a controlled step and the effects of additives and impurities on Si3N4, oxidation speed were produced by changing diffusion speed which came from the change of composition and structure in oxidation layer.
出处
《佛山陶瓷》
2005年第7期9-13,共5页
Foshan Ceramics
