MoSi_2-Mo_5Si_3复合材料的低温氧化行为

Low Temperature Oxidation Behavior of MoSi_2-Mo_5Si_3 Composites

摘要:

通过热重分析 (TGA)、X射线衍射 (XRD)和扫描电镜 (SEM)研究了 Mo Si2 - Mo5Si3复合材料的低温氧化行为 ,指出材料低温氧化时 ,随 Mo5Si3量增多 ,材料氧化加剧 ,当 Mo5Si3含量超过 16 % (质量分数 )时发生“PEST”现象 ,所形成的 Si O2 由于 Mo O3晶须的大量存在 ,使其不能均匀连续地分布于材料表面 ,从而加剧了氧化

Abstract:

The oxidation behavior of MoSi 2 Mo 5Si 3 composites at low temperature has been investigated by thermogravimetric analyses, X ray diffraction technique and SEM. The results showed that the oxidation was accelerated with the increase of Mo 5Si 3. "PEST" phenomena was caused in couse of low temperature oxidation when the content of Mo 5Si 3 exceeded 16%(mass fraction). The SiO 2 films were not distributed continuously on the surface of composite due to great amount of MoS 3 whiskers, and oxidation was accelerated.