Improved pack mixture composition for SiC pack cementation coating of carbonaceous substrates

摘要

A pack mixture composition comprising:a) Si from about 15% to about 50% by total weight of said composition;b) B from 0% up to about 25% by total weight of said composition;c) SiO₂ from about 0.01% to about 3% by total weight of said composition; andd) SiC from about 40% to about 85% by total weight of said composition, said composition being useful for the formation of a SiC pack cementation coating for protecting a carbonaceous substrate from degradation at temperatures above about 425°C (800°F).