IRON-BASE ALLOY STRUCTURAL COMPONENT HAVING A CORROSION-INHIBITING COATING

摘要

A structural component made of an iron-base alloy is provided with a corrosion inhibiting coating which has three layers, namely a primary coating or layer, an intermediate layer, and a top coating or layer. A fourth sealing coat is optional. The primary coating is a nickel or cobalt coating. The intermediate layer comprises intermetallic compounds of nickel aluminide or cobalt aluminide. The top coating is an aluminum base or aluminum alloy base high-temperature lacquer including a binder. Such a combination coating is especially resistant to fretting, oxidation and etch corrosion. The component is suitable especially for parts of gas turbine engine housings. The intermediate layer is formed after application of the primary coating and of the top coating, by a heat treatment within a reaction temperature range in which intermetallic nickel aluminum or cobalt aluminum compounds are formed.