Corrosion resistant buffer system for metal products

摘要

A system is disclosed for inhibiting the corrosion of ferrous and other metals by passivating the metals. The system includes novel buffered compositions which may be applied to metal products, and novel combinations thereof with metals, for preventing or retarding corrosion, as well as methods for applying the buffered compositions to metal products, such that corrosion protection of the products is achieved. The methods include an in-situ application to existing structures with metal reinforcement as well as applications to metal products during manufacture. Generally, the compositions may be in various forms and comprise one or more layers, at least one of which includes a water repellent but water vapor permeable carrier component and one or more pH buffer components. The buffer is selected to produce a passivating pH at the surface of the metal. The compositions are environmentally friendly and are capable of replacing chromates which have been traditionally used with zinc and zinc alloys to inhibit corrosion of metals but which are potentially harmful to the environment.