SILICON-CARBIDE FROM LASER PYROLYSIS OF POLYCARBOSILANE

Laser pyrolysis offers a means of extending solid free-form fabrication to polymeric precursors. Laser pyrolysis of polycarbosilane (PCS) produces controlled beta-SiC shapes with nanometer grain size although properties are currently limited by high porosity. By the addition of filler powders, either inert or reactive, ceramic-metal and ceramic-ceramic composite shapes are possible. The results of laser pyrolysis of PCS alone and in mixtures with beta-SIC, Al, Si, Ti, and Zr are presented showing that the technique has the potential to produce a range of materials and shapes customized to particular design requirements.