摘要:
A process is disclosed for stabilizing certain colored anodized coating on aluminum articles against degradation by ultraviolet radiation. Anodized articles colored by an electrolytic or interference process can thereafter be stabilized by heat treating them at temperatures of the order of 350° F. for a period of an hour or so. The process is particularly useful for use on electrolytically colored, anodized vehicular external body panels made from suitably formable sheet metal aluminum alloys.
摘要:
An anodized aluminum alloy comprises an aluminum alloy comprising magnesium in an amount greater than 3 weight percent based on the total weight of the aluminum alloy; and a clear porous oxide layer having a thickness greater than about 5 micrometers disposed on and into a surface of the aluminum alloy, wherein the anodized aluminum alloy has a surface gloss value greater than about 40 gloss units as measured on a gloss meter at dual illumination angles of 60° and 85°. An anodizing process comprises immersing an aluminum alloy workpiece comprising greater than 3 weight percent magnesium based on a total weight of the aluminum alloy into an anodizing solution comprising about 10 to about 25 weight percent sulfuric acid maintained at a temperature of about 18° C. to about 22° C.; applying a first direct electric current density less than or equal to about 5 amperes per square foot for a period of time sufficient to produce an oxide layer at a thickness of at least about 5 micrometers on and into a surface of the aluminum alloy workpiece; and applying a subsequent direct electric current density greater than or equal to about 10 amperes per square foot for a period of time sufficient to produce a final oxide thickness of about 10 micrometers to about 25 micrometers, wherein the oxide layer is clear and the aluminum alloy workpiece has a gloss value greater than 40 gloss units as measured by a gloss meter at dual illumination angles of 60° and 85°.
摘要:
A process is disclosed for stabilizing certain colored anodized coating on aluminum articles against degradation by ultraviolet radiation. Anodized articles colored by an electrolytic or interference process can thereafter be stabilized by heat treating them at temperatures of the order of 350° F. for a period of an hour or so. The process is particularly useful for use on electrolytically colored, anodized vehicular external body panels made from suitably formable sheet metal aluminum alloys.
摘要:
A method is disclosed for the decorative finishing of automotive vehicle bodies made of aluminum alloys. The manufactured aluminum body, or an un-assembled set of aluminum panels and components for such a body, are cleaned and otherwise pretreated as necessary and then subjected to a suitable anodizing process to form a durable, porous coating of microscopic aluminum oxide on all the visible surfaces of said body to be decorated for consumer acceptance. The anodized surfaces are then colored by coloring processes such as adsorptive coloring, electrolytic coloring and/or interference coloring.
摘要:
Some articles such as automobile components that have been constructed from steel and/or aluminum alloy parts are now being fitted with magnesium parts whose surfaces may need to be protected against corrosion. To do this an e-coating pre-film may be formed on the part's magnesium surfaces by exposing it to a conventional e-coating emulsion. And there is no need to supply a current or potential to the part or component. Magnesium's high reactivity with acidic or neutral aqueous mediums is itself a sufficient driving force to facilitate the deposition of an e-coating pre-film. At the same time any steel or aluminum alloy parts will remain unaffected. The article with a protective e-coating pre-film formed solely on its magnesium surfaces may now be advanced through a paint-line that includes conventional processes aimed at treating the component's steel and aluminum alloy parts. The process may be practiced where the magnesium surface comprises a magnesium-containing conversion or anodized coating.
摘要:
The present invention uses a two-step anodizing process to produce a colored anodized coating on the surface of an aluminum part. In accordance with this invention, a thin hard anodized coating layer is first formed on the surface of the aluminum part and then growing a softer a clear anodized coating layer on the surface of the aluminum part underneath the hard coat layer. The soft coat is essentially colorless and suitable for color finishing. This invention drastically improves the wear resistance of the aluminum part while maintaining a desired amount of clarity for effective electrolytic coloring.
摘要:
A method is disclosed for forming a clear anodized coating on an aluminum base alloy containing more than three percent by weight magnesium. The alloy surface to be anodized is treated with an aqueous solution of a mineral acid such as sulfuric acid (10 to 20%), nitric acid (10 to 30%) or phosphoric acid (40 to 80%) under the influence of a relatively low voltage direct current. This treatment suitably reduces the magnesium content of the surface layer and, subsequently, a relatively low current density anodization in sulfuric acid produces the clear coating. The clear coating may then be colored by known processes.
摘要:
The present invention uses a two-step anodizing process to produce a colored anodized coating on the surface of an aluminum part. In accordance with this invention, a thin hard anodized coating layer is first formed on the surface of the aluminum part and then growing a softer a clear anodized coating layer on the surface of the aluminum part underneath the hard coat layer. The soft coat is essentially colorless and suitable for color finishing. This invention drastically improves the wear resistance of the aluminum part while maintaining a desired amount of clarity for effective electrolytic coloring.
摘要:
Mixed-metal automotive vehicle bodies-in-white comprising ferrous metal surfaces, zinc surfaces, aluminum alloy surfaces, and magnesium alloy surfaces are cleaned and immersed in an aqueous bath comprising an adhesion promoter and an aqueous electrocoat bath (the adhesion promoter may be in the electrocoat bath. The adhesion promoter, which may be a cerium salt, is selected to react with each metal in the body surfaces to form an oxide layer that provides corrosion resistance for the surface and adherence for the deposited polymeric paint coating. The body is cathodic in the electrocoat deposition.
摘要:
A system for electro-coating a metallic substrate includes a DC power supply, a primary electrode, and a wireless auxiliary electrode. The primary electrode transmits electrical current through electrolyte fluid when energized by the power supply. The auxiliary electrode is within the drain hole, and receives the current from the fluid at one end. The auxiliary electrode boosts the calibrated voltage at the opposite end near the drain hole. In a method for depositing thin film material onto the internal surfaces, the wireless auxiliary electrode is positioned in the drain hole, and the calibrated voltage is applied from the DC power supply to the primary electrode. Electrical current transmitted through the fluid is received at the first end of the auxiliary electrode. The calibrated voltage is boosted in proximity to the drain hole at the second end of the same auxiliary electrode. A wireless auxiliary electrode assembly is also provided.