Substratos de compósitos cerâmicos no sistema Si-Al-O-N-C preparados com precursores poliméricos

Abstract

One of the advantages of the active filler controlled polymer pyrolysis process (AFCOP) is the application of the various plastic shaping technologies. In the current work, doctor blade technique was combined with polymer pyrolysis process to produce ceramic composite substrates. Substrates with thickness of 600 µm were prepared spreading a slurry on acetate film. The slurry composition comprises 60 vol% of polysiloxane and 40 vol% of active filler divided in metallic Al and Si. Due to the polymer phase in the starting mixture a flexible and thin substrate can be easily formed. The substrates were pyrolysed in nitrogen atmosphere up to 1500 °C for 2 h resulting in a thin parallel substrate. SiAlON, AlN and β-SiC are among the identified crystalline phases after pyrolysis. The substrates shown open porosity higher than 25%, and thermal expansion coefficient lower than commercially available alumina substrates.