摘要 |
Metal substrates in corrosive environments, such as gas and oil pipelines, are normally prone to embrittlement caused by absorption of the hydrogen atoms cathodically evolved during various corrosion processes. This is substantially prevented by providing an active substance in the vicinity of the metal substrate, and in electrical contact therewith, the active substance being a sulphide or mixed sulphide of a metal of Group Vb, VIb or VIIb of the Periodic Table or of a rare earth metal, especially WS2 and MoS2. The active substance is preferably applied as or in a coating on the surface of the substrate, with an overcoating of, for example, a thermosetting resin, preferably being employed for mechanical and environmental protection. |