Low‐Temperature Synthesis of Aluminum Silicon Carbide Using Ultrafine Aluminum Carbide and Silicon Carbide Powders

Abstract

The conditions for preparing α‐aluminum silicon carbide (α‐Al4SiC4) were examined by heating stoichiometric mixtures of ultrafine A14C3 and SiC powders with sizes of <0.1 μm at and below 1600°C. The starting A14C3 powder was obtained by the pyrolysis of trimiethylaluminum; the starting SiC powders were obtained by the pyrolyses of triethylsilane (3ES), tetraethylsilane (4ES), and hexamethyldisilane (6MDS). The reactivity of SiC with Al4C3 to form α‐Al4SiC4 varies according to the kind of starting alkylsilane: 3ES > 4ES > 6MDS. The reaction of 3ES‐derived SiC with A14C3 produced α‐Al4SiC4 at temperatures as low as 1400°C for 240 min, regardless of the presence of A14C3 (trace). Only α‐Al4SiC4 was formed at and above 1500°C for 60 min; the crystal growth was appreciable.