Coating system for providing environmental protection to a metal substrate, and related processes

摘要

A metal article which includes a protective coating system is described. The coating system includes a braze alloy layer and a plasma-sprayed bond coat. The bond coat may lie on top of the braze alloy layer, or the braze alloy layer may lie on top of the bond coat. In the case of a porous bond coat, partial or complete densification of the bond coat is sometimes carried out. Densification is achieved by heat treating the article, so that the braze alloy material migrates into the pores of the bond coat to a selected thickness. Related processes are also described.