Chemical vapour deposition process

Abstract From the Canadian patent

A process for producing a two element deposition coating on metals eg for oxidation/corrosion protection of superalloys comprises halide transfer of the two elements in sequence from a reaction charge, the reaction charge including a significant excess of halide activator over the amount required for stoichiometric considerations. The transportation of the first element is terminated by reacting its source to exhaustion in, the course of the transport reaction or by evacuating from the reaction vessel. Preferred elements are aluminium with silicon and aluminium with chromium.