Abstract: A laminate suitable for vehicular applications includes at least two sheets of aluminum alloy and an adhesive layer between the sheets bonding them together. An oxide layer on surfaces of the sheets is treated with a phosphorous acid electrolyte, so that a coordination number of four predominates for the aluminum-oxygen-phosphorous bond. Equivalent bonding strengths in the laminates are obtained in substantially less time with phosphorous acid treatment compared with phosphoric acid treatment.
Type:
Grant
Filed:
November 4, 1991
Date of Patent:
June 28, 1994
Assignee:
Aluminum Company of America
Inventors:
Gary A. Nitowski, Karl Wefers, Larry F. Wieserman
Abstract: The invention is in a composition and process for the chromium free passivating postrinsing of conversion layers on metals before the application of a paint or adhesive. The conversion layers can be on the bases of phosphate layers, at least two polyvalent metal ions with complex formers, titanium, zirconium and/or hafnium. The postrinsing agent is an aqueous solution which has been adjusted to a pH value of up to 5 and which contains an aluminum fluorozirconate having an Al:Zr:F mole ratio of (0.15 to 8.0):1:(5 to 52), and in which solutions the total concentration of Al+Zr+F is 0.1 to 8.0 g/l. The postrinsing solutions may additionally contain at least one of the anions benzoate, caprylate, ethyl hexoate, salicylate in a total concentration of 0.05 to 0.5 g/1 and may preferably be adjusted to the required pH value with cations of volatile bases, such as ammonium, ethanolammonium and di- and triethanolammonium.
Type:
Grant
Filed:
November 18, 1992
Date of Patent:
March 15, 1994
Assignee:
Metallgesellschaft Aktiengesellschaft
Inventors:
Dieter Hauffe, Thomas Kolberg, Gerhard Muller, Horst Gehmecker, Werner Rausch, Peter Schubach, Thomas Wendel
Abstract: This invention relates to Al plates suitable for automobile body panels and also relates to a method of pretreatment for painting. The features are: A Zn plating layer having 0.05.about.0.38 g/m.sup.2 of coating weight is formed on the surface of an Al plate or Al alloy plate by a displacement plating process or electroplating process. The coated Al or Al alloy plate is subjected to chemical conversion treatment with zinc phosphate under conditions to completely dissolve the zinc plating layer. This invention prevents the occurrence of filiform rusting and blistering after painting.
Abstract: A process for forming a protective barrier on metallic or wood surfaces to provide protection against abrasion, corrosion, heat, and fire. The process is begun by first forming a fixed surface on the metallic or wood article. On metallic articles, the fixed surface is formed by cleaning the surface and then exposing the surface to concentrated phosphoric acid. On wood, the fixed surface is formed by thoroughly cleaning the surface with hot water and detergent only. After the fixed surface is prepared, it is then exposed to a 10-16% silicate salt for at least one minute and then allowed to dry completely at 305 degrees Fahrenheit to form a first layer of silicate salt over the fixed surface. During the drying process, a portion of the sodium silicate is converted into silicon dioxide. A plurality of sodium silicate layers are then formed over the first layer of sodium silicate.
Type:
Grant
Filed:
May 22, 1991
Date of Patent:
April 27, 1993
Inventors:
Nathan C. Crews, IV, Daniel A. Young, Lance A. Young
Abstract: A final rinse for a phosphatized metal surface includes a phosphoric acid solution including aluminum chlorohydrate. The aluminum chlorohydrate solution is applied at a concentration of about 100 to about 1500 ppm at a pH of 3 to about 4.5. The pH is obtained by controlling the concentration of the phosphoric acid. This is preferably used to coat previously phosphatized metal surfaces such as iron, steel, aluminum and galvanize.
Type:
Grant
Filed:
February 28, 1991
Date of Patent:
July 7, 1992
Assignee:
Diversey Corporation
Inventors:
Thomas C. Tesdahl, Charles Ficker, Michael Askren
Abstract: A method for minimizing surface carbide formation during box annealing of DQSK steels includes as a first step treating the surface of an aluminum-killed steel suitable for production of DQSK product with an aqueous solution containing about 0.1 to 1.0 moles of phosphate ion per liter. This treatment is applied to provide a surface phosphorus concentration on the steel of at least about 10 mg P/ft.sup.2. The treated steel is then box annealed at a temperature of at least about 1250.degree. F. in a hydrogen-rich atmosphere which is non-oxidizing to steel.
Abstract: A steam iron having an acid-resistant, hydrophilic coating in the steam chamber. The steam chamber coating is provided from an acid, colloidal suspension comprising alumina, magnesia, silica, or mixtures thereof, and contains, preferably, an acid phosphate compound. In this case, particularly Al(H.sub.2 PO.sub.4).sub.3 is very suitable. The steam chamber coating is very corrosion-resistant.
Type:
Grant
Filed:
October 2, 1990
Date of Patent:
October 29, 1991
Assignee:
U.S. Philips Corporation
Inventors:
Hendrik Verweij, Paulus H. G. Offermans, Andreas P. L. Krebbers, Arend Schuurman
Abstract: The adhesion of, and corrosion protection provided by, organic surface coatings to underlying metal can be significantly improved if the degreased, etched, and pickled metal surfaces to be coated are first treated with an aqueous solution and/or dispersion of aluminum-zirconium complexes, which are obtainable as the reaction-product of a chelated aluminum component, an organo-functional ligand component, and a zirconium oxyhalide component, with the organo-functional ligand being chemically bonded to the chelated aluminum unit and the zirconium unit in the complex, and are subsequently treated with dilute aqueous solutions, emulsions, and/or dispersions of one or more inorganic and/or organic film-forming materials prior to coating the surfaces with conventional organic surface coatings.
Type:
Grant
Filed:
August 24, 1989
Date of Patent:
June 25, 1991
Assignee:
Gerhard Collardin GmbH
Inventors:
Cornelia Finnenthal, Wolf-Achim Roland, Roland Morlock
Abstract: A procedure for the application of PTFE-based, self-lubricating coating on a steel bearing element whose chrome and nickel contents are less than 5%, is disclosed. The procedure is characterized by a working process whereby the element undergoes a preparatory treatment during which crystal nuclei form, followed by phosphatization treatment which forms a microcrystalline layer composed of an iron and manganese compound, then by the application of PTFE on the surface and between the crystals.
Abstract: An inhibitor composition of sodium hexametaphosphate and a water soluble orthophosphate, together with a pH adjusting, water-soluble alkali, effectively prevents corrosion of metal surfaces by sodium chloride brines. This corrosion inhibitor can be used to prevent corrosion of motor vehicles and steel reinforcing members and structures by brines formed by roadway deicing salt.
Abstract: An aqueous surface treatment composition for forming a hydrophilic coating comprising: (a) alkali metal silicate, (b) aminoalcohol, and (c) a water-soluble resin selected from the group consisting of a water-soluble nylon, a natural polysaccharide and a water-soluble, natural protein, and/or a water-soluble silane coupling agent. This aqueous surface treatment composition is used to form a hydrophilic coating on an aluminum surface having a corrosion-resistant coating layer. The hydrophilic coating prepared from this compositon has good hydrophilic nature and corrosion resistance with substantially no unacceptable odor.
Abstract: A process for improving the corrosion resistance of an iron or steel part having a phosphate conversion coating, said method comprising contact of said part with a solution containing ions selected from the group of cobalt ions and nickel ions. Preferably, the solution also containing stannous ions. Contact may be by immersion or spraying.