Conversion of a Precursor Derived from Cage‐Type and Cyclic Molecular Building Blocks into Al‐Si‐N‐C Ceramic Composites

Abstract

A precursor derived from (HAlN i Pr) m and [MeSi(H)NH] n , which mainly consisted of cage‐type compounds and cyclic compounds, respectively, was converted into Al‐Si‐N‐C ceramic composites via pyrolysis. A dehydrocoupling reaction between AlH groups and NH groups occurred at low temperatures (≤∼250°C), which mainly accounts for its high ceramic yield (69% up to 900°C). At high temperatures (≥∼250°C), the organic groups were decomposed. The product pyrolyzed at 1350° and 1500°C under Ar contained a 2H wurtzite‐type compound and a β‐Si 3 N 4 ‐type compound, while β‐SiC was clearly detected in addition to these compounds in the product pyrolyzed at 1600°C under Ar. On the other hand, the product pyrolyzed at 800°C under NH 3 and subsequently at 1350°C under N 2 consisted of AlN and β‐Sialon.