二硅化钼材料在Co和N_2混合气氛条件下使用时的破坏机理  

Damnification Mechanism of MoSi_2 Heater by CO and N_2

作　　者：王刚[1] 张红波[2] 周继伟[2] 江莞[1] 

机构地区：[1]中国科学院上海硅酸盐研究所高性能陶瓷和超微结构国家重点实验室,上海200050 [2]中钢集团洛阳耐火材料研究院,河南洛阳471039

出　　处：《稀有金属材料与工程》2007年第A02期449-451,共3页Rare Metal Materials and Engineering

摘　　要：考察了二硅化钼电热材料在CO和N_2混合气氛条件下使用破坏机理。结果表明,在这种非氧化气份条件下,二硅化钼材料表面很难生成氧化物保护膜;二硅化钼材料表面发生脱硅反应,生成低硅化物,甚至MoC,在表面形成变质层。在频繁的升降温过程中,由于表面变质层与基体的热膨胀系数不同,发生剥落。从而导致二硅化钼材料在这种特出气氛条件下使用寿命的降低。Damnification mechanism of MoSi2 composites by CO and N2 atmosphere is investigated. The result shows that a protective film in the surface of MoSi2 composites cannot form at CO and N2 atmosphere, which is not as at oxidative atmosphere; removed-silicon phenomena take place on the surface of MoSi2 composites and a degenerative layer forms; the degenerative layer can be flaked off in service because its expansion rate is different form that of the matrix. That is the reason why the working life of MoSi2 heater at CO and N2 atmosphere is shorter than at oxidative atmosphere.

关 键 词：二硅化钼 CO和N2混合气氛 破坏机理 

分 类 号：TB34[一般工业技术—材料科学与工程]