Characterization of Organosilicon-Infiltrated Porous Reaction-Sintered Si3N4

Polymeric organosilicon compounds such as hexaphenylcyclo‐trisilazane and methylphenyl polysilane were used to infiltrate porous reaction‐sintered silicon nitride. The in situ thermal decomposition of the infiltrated body under controlled atmosphere and temperature resulted in pronounced changes in the microstructure, increased densities, and significantly improved room‐temperature strength. The silicon oxynitride phase present in some as‐received materials is eliminated and the ratio of α‐ to β‐phase silicon nitride increases during infiltration processing