Oxynitride glasses in the system Mg-Ca-Al-Si-O-N prepared with the aid of a polymeric precursor: preparation and properties

Oxynitride glasses in the system Mg-Ca-Al-Si-O-N were prepared from a polymeric, electrochemically derived precursor solution, yielding aluminum nitride in a subsequent pyrolysis and an oxidic glass prepared by melting. This mixture was dried and calcined under ammonia resulting in amorphous powders. The homogeneity of the powder batch used hereby reduced the melting and soaking times to 1-8 min at temperatures between 1500 and 1700 degrees C, hence, facilitating the formation of homogeneous oxynitride glasses. Their density and mechanical properties increased with the nitrogen content the linear thermal expansion coefficient decreased. (C) 1997 Elsevier Science B.V.