Ceramics are used increasingly for structural applications in view of their high temperature stability and high hardness. Unfortunately most ceramics are very brittle and possess low fracture toughness values. One way to increase the toughness of structural ceramic materials is to prepare composites with ceramic whiskers as reinforcing fillers. The methods for producing these fillers currently are rather expensive. The P.I. proposes a simple new method of producing Beta-sialon fiber in SiO2/C/Na3 AIF6 mixed melt in flowing nitrogen gas. The proposed research will address the yield and structure of Beta-sialon whiskers, reaction mechanism and optimum processing conditions.