Method for producing pre-shaped alpha-silicon nitride whisker compacts and loose whiskers for composite material reinforcement

摘要

Method for producing pre-shaped a-silicon nitride whisker compacts and loose whiskers for composite material reinforcement, lies in the field of producing uncontaminated silicon nitride whiskers which previously could not be accomplished without high cost. The present invention provides for production of uncontaminated a-silicon nitride whiskers at a reasonable cost as either shaped preform or individual whiskers by blending silicon particles with composition particles, compacting the blend of silicon and composition particles to a shaped preform, subliming the composition particles to produce a shaped porous silicon precursor, and reacting the precursor with nitrogen. The shaped whisker compact can be impregnated with various materials to form composites, or can be broken down to individual whiskers to be used in molding powders.