Effect of Al as Active Filler on Properties of Preceramic-derived Multi-phased Ceramics

Al and SiC powders were chosen as active filler and inert filler,respectively,for the fab- rication of preceramic-derived multi-phased ceramics,using polycarbosilane as preceramic precursor. The effects of pyrolysis temperature and soaking time on ceramic yield,linear shrinkage,mechanical properties and microstucture were investigated.Volume expansion was observed due to the reaction of A1 particles with carbon-containing pyrolysis products and reactive atmosphere.The derived ceramics with small shrinkage and high ceramic yield could meet the demand of near net shaping process.After the ceramic composite was pyrolyzed at 1000℃for 1h,the bending strength reached 293MPa with the shrinkage of 0.08% and ceramic yield of 99.68%.