Microstructural effects on properties and new processing techniques of Silicon Nitride. Part II: New processing techniques of silicon nitride

In part I of this paper the relationship between microstructure and various mechanical, thermal and thermo‐mechanical properties of hot‐pressed and reaction‐bonded silicon nitride, such as fracture strength, thermal diffusivity and thermal shock resistance, was discussed. On the basis of this correlation today's limits of silicon nitride regarding a broader application and the possibilities for optimizing this material group were outlined. This discussion demonstrates the necessity of further improving some important properties and of developing new processing techniques. In part II the development lines of these new techniques for silicon nitride processing are discussed and a survey is given of recent progresses in the use of those techniques. As an example of a new processing technique, results of hot‐isostatic pressing of reaction‐bonded silicon nitride are presented in more detail.