Fundamental Studies of High Pressure Self-Sustaining Synthesis of Silicon Nitride Based Ceramics

摘要- Puszynski 这是一个高压合成硅的基本原理的研究- 氮化物基陶瓷在一个自我维持制度。 调查的方面 包括颗粒-颗粒-气体相互作用、产物形态和相 燃烧合成陶瓷的组成。 努力的重点是 燃烧条件和各种添加剂的影响，可能改变 晶体生长和氮化硅基 陶瓷. 获得了晶体形成和生长的定量数据 氮化硅、氮氧化硅、赛隆和碳化硅在自- 含有一定量的 氧化物、氮化物、卤素和/或碳。 模型被开发来描述 粒子水平上的复杂反应和扩散过程， 形成单相氮化硅和其它固溶体。 高性能氮化物陶瓷的广泛应用受到了限制 合成和加工成本。 燃烧合成是一种很有吸引力的方法 克服这个障碍。 基于氮化硅的陶瓷对于 许多高科技应用，因为它们的化学惰性，高， 温度稳定性、断裂韧性和抗侵蚀、腐蚀 和热冲击。

Abstract - Puszynski This is a study of the fundamentals of high-pressure synthesis of silicon- nitride-based ceramics in a self-sustaining regime. Aspects investigated include particle-particle-gas interactions, product morphology, and phase composition of combustion-synthesized ceramics. The effort focuses on the effects of combustion conditions and various additives, factors that may alter crystal growth and the formation mechanisms of silicon-nitride-based ceramics. Quantitative data are obtained on the formation and crystal growth of silicon nitride, silicon oxynitride, sialon, and silicon carbide during self- sustaining, high-pressure nitridation of silicon powders containing amounts of oxides, nitrides, halogens, and/or carbon. Models are developed to describe the complex reaction and diffusion processes on a particle level during formation of single-phase silicon nitride and other solid solutions. Widespread application of advanced nitride ceramics is limited by high synthesis and processing costs. Combustion synthesis is an attractive method for overcoming this obstacle. Silicon-nitride-based ceramics are attractive for many high-technology applications because of their chemical inertness, high- temperature stability, fracture toughness and resistance to erosion, corrosion, and thermal shock.