A method for manufacturing a component for a gas hob, the method comprising treating a surface by plasma electrolytic oxidation.

A method for manufacturing a component for a gas hob, the method comprising treating a surface by plasma electrolytic oxidation.

A method of growing a hierarchically structured anodized film to an aluminum substrate including growing a Phosphoric Acid Anodizing (PAA) film layer to an aluminum substrate and growing a multiple of Tartaric-Sulfuric Acid Anodizing (TSA) film layers under the Phosphoric Acid Anodizing (PAA) film layer.

A method of growing a hierarchically structured anodized film to an aluminum substrate including growing a Phosphoric Acid Anodizing (PAA) film layer to an aluminum substrate and growing a multiple of Tartaric-Sulfuric Acid Anodizing (TSA) film layers under the Phosphoric Acid Anodizing (PAA) film layer.

An aluminum-based coating of a flat steel product is applied in a hot-dipping method and comprises a mass percentage of silicon within a given range. The coating for a flat steel product, in particular for press mold hardening components, offers a shortened required minimum oven dwell time and a sufficiently large processing window when heating in an oven. This is achieved in that the surface of the coating has a degree of absorption for thermal radiation ranging between 0.35 and 0.95 prior to an annealing treatment, where the degree of absorption relates to an oven temperature ranging from 880 to 950° C. during the austenitizing annealing treatment. The invention additionally relates to an improved method for producing a flat steel product with an aluminum-based coating, to an inexpensive method for producing press-hardened components from such flat steel products, and to a press-hardened component made of such flat steel products.

A method for producing a ceramic coating on the surface of an aluminum alloy substrate by means of plasma electrolytic oxidation may include immersing the substrate as an electrode together with a counter-electrode in an alkaline electrolytic aqueous solution. The method may also include the step of applying an electrical potential sufficient to generate spark discharges on the surface of the substrate for a predefined period of treatment time so as to lead to the formation of the coating. The coating may be aluminum oxides and oxides of any alloying agents of the alloy. The electrolytic aqueous solution may have from 9 to 14 g/l of Na2SiO3, from 2.3 to 2.8 g/l of K3PO4, not less than 5 g/l of Na2WO4.Math.2H20, from 0.4 to 1.5 g/l of Na3AlF6, and NaOH at a concentration such that the electrolytic solution has a pH between 11.8 and 12.0, and a conductivity between 9.5 and 10.5 mS/cm.

A method for producing a ceramic coating on the surface of an aluminum alloy substrate by means of plasma electrolytic oxidation may include immersing the substrate as an electrode together with a counter-electrode in an alkaline electrolytic aqueous solution. The method may also include the step of applying an electrical potential sufficient to generate spark discharges on the surface of the substrate for a predefined period of treatment time so as to lead to the formation of the coating. The coating may be aluminum oxides and oxides of any alloying agents of the alloy. The electrolytic aqueous solution may have from 9 to 14 g/l of Na2SiO3, from 2.3 to 2.8 g/l of K3PO4, not less than 5 g/l of Na2WO4.Math.2H20, from 0.4 to 1.5 g/l of Na3AlF6, and NaOH at a concentration such that the electrolytic solution has a pH between 11.8 and 12.0, and a conductivity between 9.5 and 10.5 mS/cm.

Disclosed are a GM type cryogenic refrigerator rotary valve and a preparation method therefor. The GM type cryogenic refrigerator rotary valve comprises an aluminum alloy rotating valve and an alumina ceramic membrane. A valve body of the aluminum alloy rotating valve is provided with a first surface for arranging a working boss and a second surface opposite to the first surface; and a high-pressure hole and a low-pressure groove are both provided in the working boss, and a vent hole is provided in the first surface; the high-pressure hole and the vent hole both penetrate the valve body, and an air chamber is formed on the second surface. The alumina ceramic membrane is plated on surface of the aluminum alloy rotating valve. The preparation method comprises: plating an alumina ceramic membrane on surface of an aluminum alloy rotating valve by means of a micro-arc oxidation process.

Disclosed are a GM type cryogenic refrigerator rotary valve and a preparation method therefor. The GM type cryogenic refrigerator rotary valve comprises an aluminum alloy rotating valve and an alumina ceramic membrane. A valve body of the aluminum alloy rotating valve is provided with a first surface for arranging a working boss and a second surface opposite to the first surface; and a high-pressure hole and a low-pressure groove are both provided in the working boss, and a vent hole is provided in the first surface; the high-pressure hole and the vent hole both penetrate the valve body, and an air chamber is formed on the second surface. The alumina ceramic membrane is plated on surface of the aluminum alloy rotating valve. The preparation method comprises: plating an alumina ceramic membrane on surface of an aluminum alloy rotating valve by means of a micro-arc oxidation process.

The aluminum member of the present disclosure includes a mother material containing aluminum or an aluminum alloy, and an anodic oxide film on the surface of the mother material, in which the arithmetical mean roughness Ra, the mean length of roughness curve elements RSm, and the Hunter whiteness of the aluminum member, measured from the surface side of the anodic oxide film, are 0.1 μm or more, 10 μm or less, and 60 to 90, respectively.