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AssigneeThe Boeing Company
InventorsJ. Arthur Marceau, Ralph H. Firminhac, Yukimori Moji
Estimating the term…
Environmentally stable bond joints of aluminum metal and aluminum alloys in adhesively joined structures are formed by utilizing a prebonding anodization of the aluminum surfaces in a phosphoric acid electrolyte containing from about 1.5 to about 50% H.sub.3 PO.sub.4 at 1 to 50 volts for a period of 5 to 60 minutes using a bath temperature of 50.degree. to 100.degree. F. The anodized surface is then washed free of electrolyte, dried and coated with an adhesive resin. The aluminum metal segments are then arranged in a composite arrangement and bonded together under pressure and heat to cure the adhesive resin. The resulting structure is resistant to failure of the bond joints on exposure to moist atmospheric conditions. The surface preparation provides a hydration resistant aluminum oxide surface which minimizes adhesive-aluminum separation under aqueous exposure. Alloys containing copper and other alloying constituents may be successfully anodized and bonded by this process.
A method of preparing an adhesively bonded aluminum structure comprising
A process for preparing an adhesively bonded structure of copper-containing aluminum alloy adherends wherein said adherends have a polymer receptive aluminum oxide surface thereon having a porous columnar structure with a thickness of from about 500 to about 600 Angstroms, having pores from about 300 to about 600 Angstroms in diameter and from about 400 to about 5000 Angstroms in depth extending into said oxide surface, said structure prepared by the steps of:
An adhesively bonded alumimum alloy structure formed by adhesively bonding together aluminum adherends containing from about 1.6 to about 4.5% by weight copper, said adherends each having a polymer receptive aluminum oxide surface thereon having a porous columnar structure with a thickness of from about 500 to about 6000 Angstroms, having pores from about 300 to about 600 Angstroms in diameter and from about 400 to about 5000 Angstroms in depth extending into said oxide surface, said structure prepared by anodizing the surfaces of said adherends in an aqueous phosphoric acid solution containing from about 3 to about 20% by weight H.sub.3 PO.sub.4 at a temperature of from about 50.degree. F. to about 85.degree. F. for about 10 to about 30 minutes at a potential of from about 3 to about 25 volts, rinsing said adherends to remove said solution, applying a polymeric adhesive to said surfaces and bonding said adherends together.
A method of preparing an adhesively bonded aluminum structure comprising:
An adhesively bonded structure formed by bonding together aluminum adherends, each adhered having a polymer receptive hydration-resistant, aluminum oxide surface thereon, said oxide surface having a porous columnar structure with a thickness of from about 500 to about 6,000 Angstroms, having pores from about 300 to about 600 Angstroms in diameter and from about 400 to about 5,000 Angstroms in depth extending into said oxide surface, said surface prepared by anodizing the surface of said adherend in an aqueous acidic electrolyte, the acidic component of said electrolyte consisting essentially of H.sub.3 PO.sub.4 present in amounts from about 3 to about 20% by weight H.sub.3 PO.sub.4 at a temperature of from about 60.degree. F. to about 90.degree. F. for about 10 to about 30 minutes at a potential of from about 3 to about 25 volts, rinsing said adherend to remove said solution, applying an adhesive to said surfaces and bonding said adherends together to form said adhesively bonded structure.
A process for preparing an adhesively bonded aluminum structure from aluminum adherends comprising the steps of:
Dependencies are inferred from the claim text.