Metallic substrate treatment methods and articles comprising a phosphonate functionalized layer are provided. The method comprises contacting a metallic substrate comprising at least one of aluminum and an aluminum alloy with a fluid to form a phosphonate functionalized layer on at least a region of the metallic substrate. The fluid comprises at least one of a phosphonate containing acid and a derivative thereof. At least one of the phosphonate containing acid and the derivative thereof comprises a pKa of a first acidic proton. The fluid comprises a pH at least 0.5 pH value greater than the pKa of the first acidic proton. The article comprises a metallic substrate comprising aluminum or an aluminum alloy and a phosphonate functionalized layer on at least a region of the metallic substrate.

The present invention relates to a method for the corrosion-protective and cleaning pretreatment of metallic components, produced at least partially from metallic materials from the elements iron, zinc and/or aluminum, with the use of an acid aqueous composition containing, in addition to the water-soluble compounds of the elements Zr and/or Ti causing the conversion of the metal surface, a mixture of an aliphatic diol and an aliphatic saturated polyhydroxy compound. It also comprises a chrome(VI)-free aqueous composition based on the constituents mentioned above which delivers outstanding results in cleaning and simultaneous corrosion-protective conversion of technical metal surfaces in one method step.

An acidic treatment liquid processing apparatus includes: a tank having an interior space; a diaphragm permeable to a metal cation and separating the interior space of the tank into a first chamber and a second chamber; a first electrode disposed in the first chamber; a second electrode disposed in the second chamber; a power supply configured to apply a voltage while using the first electrode as an anode and the second electrode as a cathode; a first liquid passing part configured to pass an acidic treatment liquid containing a dichromate ion and a metal cation into the first chamber; and a second liquid passing part configured to pass an acid aqueous solution into the second chamber.

In an acidic treatment liquid processing apparatus, a space between a first electrode and a second electrode spaced from each other is separated by a first diaphragm permeable and a second diaphragm into a first chamber, a second chamber, and a third chamber. While the first chamber is fed with an acidic treatment liquid containing a dichromate ion and a metal cation, the second chamber is fed with a first acid aqueous solution, and the third chamber is fed with a second acid aqueous solution, a voltage is applied using the first electrode as an anode and the second electrode as a cathode.

Described herein is a continuous coil pretreatment process used to treat the surface of an aluminum alloy sheet or coil for subsequent deposition of an acidic organophosphorus compound. The process can include applying a cleaner to a surface of an aluminum sheet or a coil; etching the surface of the aluminum sheet or the coil with an acidic solution; rinsing the surface of the aluminum sheet or the coil with deionized water; applying to the surface of the aluminum sheet or the coil a solution of an acidic organophosphorus compound; rinsing the surface of the aluminum sheet or the coil with deionized water; and drying the surface of the aluminum sheet or the coil.

A method for producing a heat exchanger having at least one cooling line with a lightweight metal base through which a water-based coolant can flow may include passivating a surface of the at least one cooling line, which is in contact with the coolant, before the at least one cooling line is filled with the coolant.

The invention relates to a continuous coil surface treatment process suitable for both a coil of a 5XXX aluminum alloy sheet and of a 6XXX aluminum alloy sheet. The process comprises the successive steps of etching the surface with a fluorine-free acidic solution; rinsing with deionized water; applying a conversion solution comprising titanium and zirconium, and drying. The invention surface treatment method is environmentally friendly and enables the production of the treated surfaces in an efficient and reliable manner for both 5XXX and 6XXX alloys. It is particularly adapted for the production of aluminum alloy sheets for the automotive industry.

Provided is an alloy member including a substrate made of magnesium-lithium alloy with a sum of content of magnesium and content of lithium of 90 mass % or more and a coating film disposed on the substrate. The coating film contains fluorine and oxygen, with a fluorine content of more than 50 atom % and an oxygen content of less than 5 atom %.

The present invention aims to provide an etchant that can provide good deposition of a metal plating such as a nickel plating, despite its acidity, and a method of surface treatment of aluminum or an aluminum alloy using the etchant. Included is an etchant containing a zinc compound and a fluorine compound and having a pH of 4.5 to 6.5.

A metal sheet is provided. The metal sheet includes a substrate having two faces, each face hot dip coated with a metal coating of zinc, aluminum and magnesium. The metal coatings include between 0.1 and 20 wt % of aluminum and 0.1 and 10 wt % of magnesium. Layers of magnesium oxide or magnesium hydroxide are formed on outer surfaces of the metal coatings. The layers are altered by applying an acid solution on the outer surfaces of the metal coatings or by applying mechanical forces using a roller leveler, a brushing device, or a shot-blasting device on the outer surfaces of the metal coatings. The metal sheet also includes a layer of oil deposited directly on the outer surfaces of the metal coatings.