Growth of Mullite Coatings by Chemical Vapor Deposition

在SGER奖下，研究了莫来石（3al2o3）薄膜生长的可行性。将研究二氧化硅（SiO2）在陶瓷衬底上的作用。沉积方法是化学气相沉积超薄层的组成化合物，然后进行沉积后的热处理，通过相互扩散形成莫来石。开发碳化硅和氮化硅陶瓷衬底的最佳抗氧化性能、抗钠侵蚀性能、热循环抗剥落性能和硬度的工艺特性。通过这种技术在这些基底上沉积功能梯度涂层的可能性也将被评估。

Under an SGER award the feasibility of growing thin coatings of mullite (3 Al2O3 . 2 SiO2) on ceramic substrates will be studied. The deposition method will be chemical vapor deposition of ultra- thin layers of the constituent compounds, followed by post- deposition heat treatment to form the mullite by inter diffusion. Process characteristics for development of optimal properties of oxidation resistance, resistance to sodium attack, spall resistance during thermal cycling, and hardness will be developed for substrates of silicon carbide and silicon nitride ceramics. The possibility of depositing functionally graded coatings by this technique on these substrates will also be evaluated.