Bethlehem Steel Corporation

Robert G Hart

Herbert E Townsend

This invention is directed to a coating method and to the product produced by such method. In the preferred practice of this invention, the method includes the steps of selecting a ferrous substrate, such as steel sheet preferably containing a first coating having certain corrosion resistant and adhesion-promoting characteristics, and applying thereto an outer coating of an organic resin containing a particulate metallic aluminum-zinc alloy which is between 5 and 95% by weight aluminum, balance zinc. Preferably, the particle size of said alloy is no more than about 10 microns. Such product is ideally suited for the subsequent application of a cathodic electrophoretic primer coat, such as widely used in the automotive industry.

Coating method and product thereof

The present invention relates to the method of producing a metal-filled organic coating on a substrate, which coating provides enhanced corrosion protection to said substrate, and to the product of such method. More particularly, this invention is directed to the enhancement of the corrosion resistant properties of zinc-rich organic coatings by subjecting such coatings to an electric discharge such as in corona discharge treatment.

Method of producing improved metal-filled organic coatings and product

This invention is directed to a coating method. In the preferred practice of this invention, the method includes the steps of selecting a ferrous substrate, such as steel sheet preferably containing a first coating having certain corrosion resistant and adhesion-promoting characteristics, applying thereto an outer coating of an organic resin containing a particulate metal selected from the group consisting of Al, Ni, Cr, Fe, Mn, Cu, Mo, Co, Ag, Au and alloys thereof, where the particle size of said metal or alloy is prefereably no more than about 10 microns, and applying thereover a cathodic electrophoretic coating at voltages of at least 300 V. The product of such method is corrosion resistant, free of craters or pores, and is readily welable prior to the application of said cathodic electrophoretic coating.

Method of producing metal-filled organic coating

This invention is directed to a method for producing a corrosion-resistant, composite product, such as sheet and strip, having a thin, uniformly black, light-absorptive surface layer thereon, and to the product of such method. The method includes the steps of treating a product having a coating containing both zinc and aluminum, such as galvanized strip, or up to 70% by weight, aluminum, balance essentially zinc coated strip, with an aqueous alkaline solution for a sufficient time to form a zinc-rich surface on said product, which surface is reactive with a blackening bath containing Ni and Sb, and subjecting such treated product to such blackening bath to form said thin, uniform, light-absorptive surface layer on said product. The light-absorptive surface layer has a thickness of at least 80 nm, preferably between about 100-400 nm, and an absorptance greater than about 95% over the solar radiation spectrum.

Growing community of inventors

Bethlehem, PA, United States of America

Robert G Hart