Abstract: A metal article is improved on its surface for the purpose of plating thereon by treatment with an additive of an anionic, cationic or amphoteric and water-soluble or water-self-dispersible organic polymer J, K or L. J is a polymer having an aromatic ring and OH group and a polar group. K is a polymer of hydroxystyrene having a polar group. L is a copolymer of hydroxystyrene having a polar group and a vinyl compound. The parted article is improved in corrosion resistance.
Abstract: A non-toxic corrosion resistant conversion coating for aluminum is formed by a process which includes subjecting the aluminum to an acidic aqueous solution containing potassium permanganate and cerous chloride, alone or in combination with strontium chloride. The corrosion resistance is improved by a subsequent treatment in an alkaline solution containing molybdate, nitrite and metasilicate ions. The corrosion resistant is further improved by treating the coated surface with an alcoholic solution containing glycidoxy(epoxy)polyfunctionalmethoxysilane, alone or in combination with phenyltrimethoxysilane. The coating thus produced is a mixture of oxides and hydroxides of cerium strontium and aluminum. These oxides and hydroxides may also be intermixed with molybdate silicate and nitrite ions. In the most corrosion resistant form the mixture further includes a silane overcoat.
Abstract: A method for treating the surface of an aluminum-based material so as to make the surface resistant to corrosion includes the steps of contacting the surface with an aqueous cerium non-halide solution and then contacting the surface with an aqueous cerium halide solution. These steps may optionally be followed by a step of positively charging the metal surface while in contact with an aqueous molybdenum solution.
Type:
Grant
Filed:
July 20, 1990
Date of Patent:
March 16, 1993
Assignee:
The University of Southern California
Inventors:
Florian B. Mansfeld, Hong Shih, You Wang
Abstract: An method of providing a protective coating on the surface of aluminum or aluminum alloys, comprising: removing contaminants from the surface; exposing the surface to water at 50.degree. to 100.degree. C. to form a porous boehmite coating on the surface; and exposing the boehmite-coated surface to an aqueous solution comprising a cerium salt and a metal nitrate at a temperature of 70.degree. to 100.degree. C. Oxides and hydroxides of cerium are formed within the pores of the boehmite to provide the protective coating, which provides corrosion resistance and improved paint adhesion.
Abstract: An aqueous liquid combination of simple and complex fluorides, a chelating agent for iron, phosphate ions, a hydroxylamine source, and an oxidizing agent selected from among water soluble nitroaromatic organic compounds, molybdates, and tungstates, provides good quality protective phosphate conversion coatings on ferrous, zinciferous, aluminous, and magnesium and magnesium alloy metal surfaces, without needing any divalent or higher valent metal cations such as are generally used to produce high quality phosphate conversion coatings. If the combination includes suitable surfactants, no prior chemical cleaning of the metal to be treated is required for good results.
Abstract: A process is disclosed for forming a protective metal coating on a metal surface using a flux consisting of an alkali metal fluoride, an alkaline earth metal fluoride, an alkali metal fluoaluminate, an alkali metal fluosilicate, and mixtures thereof. The flux, in particulate form, is mixed with particles of a metal coating material which may comprise aluminum, chromium, mixtures thereof, and alloys containing at least 50 wt. % aluminum and the particulate mixture is applied to the metal surface in a single step, followed by heating the coated metal surface to a temperature sufficient to cause the metal coating material to react with the metal surface to form a protective reaction product in the form of a metal coating bonded to the metal surface. The metal surface which reacts with the metal coating material to form the protective coating may comprise Fe, Co, Ni, Ti, V, Cr, Mn, Zr, Nb, Mo, Tc, Hf, Ta, W, Re and alloys thereof.
Type:
Grant
Filed:
August 7, 1990
Date of Patent:
March 31, 1992
Assignee:
The United States of America as represented by the United States Department of Energy
Abstract: This invention relates to a process for coating a surface of a metal I, such as iron, steel, zinc, copper, tin or aluminum with a hydroxy oxime complex of metal II which may be lead of zinc. The complex can be incorporated in a surface coating composition.
Type:
Grant
Filed:
April 20, 1989
Date of Patent:
September 10, 1991
Assignee:
Imperial Chemical Industrials, PLC
Inventors:
Bernard Tury, Glyn R. John, Noreen L. Thomas
Abstract: This invention provides an aluminum alloy conversion coating composition and a process for protecting aluminum alloys, especially the alloys having greater than 1.0% Cu with a conversion coating. The coating is placed on the aluminum alloy in a multi-step process. In a first step the alloy is treated with a composition having as essential ingredients aluminum nitrate and an alkali metal nitrate, in a second step the nitrate treated alloy is treated with an alkali metal permanganate composition and in the final step the alloy is treated with an alkali metal silicate composition.The aluminum conversion coatings of this invention are provided without the need for using toxic chromium compounds.
Abstract: Zinc and zinc alloy surfaces can be given an effective corrosion inhibiting treatment by contact for less than a minute with an alkaline aqueous solution having a pH not more than 11 and containing at least 0.020 g/L of dissolved nickel ions and sufficient ammonia to give a molar ratio of ammonia to nickel ion of at least 6. If the concentration of nickel ions in the treating solution is at least 1.0 g/L, a durable blackening of the surface is also produced. Both the corrosion resistance and the quality of the blackening can usually be further improved by subsequent conventional phosphate conversion coating.
Abstract: A sterile surgical needle having a dark, non-reflective and non-flaking surface. The needle is produced by selecting an appropriately shaped needle having the desired degree of sharpness. The needle is treated to activate the surface and then immersed in a solution of sulfuric acid, potassium dichromate and water to form a dark, non-reflective, non-flaking surface. The needle is sterilized to produce a sterile surgical needle of improved visibility.
Abstract: A method of rendering an aluminum base metal surface resistant to water staining is provided which comprises providing an aluminum base metal surface and applying a stain resistant coating to the aluminum base metal surface, with the stain resistant coating containing a water soluble molybdate salt and water soluble nitrite compound in an amount sufficient to render the aluminum base metal surface resistant to water staining. An aluminum base metal article of manufacture which is resistant to water staining is also provided.
Type:
Grant
Filed:
May 5, 1988
Date of Patent:
July 11, 1989
Assignee:
AMAX Inc.
Inventors:
Charles A. Natalie, Julianne Bates, Mark S. Vukasovich