高温新材料Si(B)CN

A New High Temperature Material Si(B)CN

碳氮化硅 (Si CN)和含硼的碳氮化硅 (Si BCN)在 140 0℃以上的高温仍保持非晶态结构 ,具有比 Si C、Si3N4更好的高温性能。 Si CN的玻璃转变温度 Tg大于 140 0℃ ,在此温度以上开始有晶体析出 ,最终为多晶 Si C和 Si3N4。Si BCN在 170 0℃仍保持非晶态 ,于 180 0℃以上开始析晶。这两种材料在 16 0 0℃表现出极好的抗氧化性能。按照高温材料的要求 ,论述了这两类材料的高温热稳定性、抗氧化性以及抗蠕变性能。展望了该材料作为高温陶瓷材料的发展趋势。

Amorphous silicon carbonitride (SiCN) and boron containing silicon carbonitride (SiBCN) have better high temperature properties than silicon carbide (SiC) and silicon nitride(Si 3N 4) The glass transition temperature (T g) of SiCN is above 1400℃,and start to decompose to polycrystalline of SiC and Si 3N 4 The SiBCN material remains amorphous at temperature up to 1700℃ and begin to crystallize above 1800℃ SiCN and SiBCN have an excellent resistance to oxidation at 1600℃ According to the needs of high temperature materials, we discuss the thermal stability, oxidation resistance, and resistance to creep of those materials, respectively Prospect the development of SiCN and SiBCN as high temperature ceramic materials