A pretreatment method for pretreating components, which are each formed of at least two different materials, prior to a coating process. The pretreatment method includes the steps: alkaline degreasing; chemical pickling in a first pickling medium; anodic pickling in a second pickling medium; and cathodic degreasing.

The invention relates to a method for manufacturing strips of stainless steel, comprising hot rolling in an initial process (A) and subsequently cold rolling in a cold rolling line (B). The hot rolling is stopped when the strip thickness has been reduced to a thickness between 2.0 mm and 6.5 mm. The subsequent cold rolling is passed at least one time through said cold rolling line, which comprises in the following order: At least one cold rolling mill (11-13) in the initial part of the line, at least one annealing section (17), a scale breaking step (21), a shot blasting step (23) and at least one pickling section (26, 27) utilizing a mixture of nitric acid HNO.sub.3, hydrofluoric acid HF and optionally sulphuric acid H.sub.2SO.sub.4.

The invention relates to a method for manufacturing strips of stainless steel, comprising hot rolling in an initial process (A) and subsequently cold rolling in a cold rolling line (B). The hot rolling is stopped when the strip thickness has been reduced to a thickness between 2.0 mm and 6.5 mm. The subsequent cold rolling is passed at least one time through said cold rolling line, which comprises in the following order: At least one cold rolling mill (11-13) in the initial part of the line, at least one annealing section (17), a scale breaking step (21), a shot blasting step (23) and at least one pickling section (26, 27) utilizing a mixture of nitric acid HNO.sub.3, hydrofluoric acid HF and optionally sulphuric acid H.sub.2SO.sub.4.

Disclosed herein is an electrolytic brush assembly comprising a handle assembly; a shroud extending from the handle assembly, the shroud having an aperture at a distal end thereof; a brush connecting assembly for releasably connecting a brush to the handle assembly whereby the brush extends through the aperture of the shroud and a fluid delivery assembly. The handle assembly comprises an adjustment sub-assembly for selectively moving the brush connecting assembly and a brush connected thereto relative to the handle assembly and the aperture of the shroud. The fluid delivery assembly delivers electrolytic fluid to the proximity of the brush, optionally under closed loop control.

Disclosed herein is an electrolytic brush assembly comprising a handle assembly; a shroud extending from the handle assembly, the shroud having an aperture at a distal end thereof; a brush connecting assembly for releasably connecting a brush to the handle assembly whereby the brush extends through the aperture of the shroud and a fluid delivery assembly. The handle assembly comprises an adjustment sub-assembly for selectively moving the brush connecting assembly and a brush connected thereto relative to the handle assembly and the aperture of the shroud. The fluid delivery assembly delivers electrolytic fluid to the proximity of the brush, optionally under closed loop control.

A passivation surface treatment method of stainless steel that improves corrosion resistance including in a brine environment without changing the appearance of the surface of stainless steel. A passivation surface treatment method for stainless steel includes: performing degreasing of stainless steel, performing electrolytic pickling where the stainless steel that underwent the degreasing is immersed in a pickling solution having phosphoric acid (H.sub.3PO.sub.4) and is connected to the anode and a voltage of about 0.5 to 5.0 V for about 10 seconds or more is applied, performing electrolytic degreasing of the stainless steel, and performing electrolytic passivation where the stainless steel that underwent the electrolytic degreasing is immersed in a passivation solution including dichromic acid and chromium sulfate and a voltage of about 0.5 to 5.0 V is applied for 5 seconds or more.

A passivation surface treatment method of stainless steel that improves corrosion resistance including in a brine environment without changing the appearance of the surface of stainless steel. A passivation surface treatment method for stainless steel includes: performing degreasing of stainless steel, performing electrolytic pickling where the stainless steel that underwent the degreasing is immersed in a pickling solution having phosphoric acid (H.sub.3PO.sub.4) and is connected to the anode and a voltage of about 0.5 to 5.0 V for about 10 seconds or more is applied, performing electrolytic degreasing of the stainless steel, and performing electrolytic passivation where the stainless steel that underwent the electrolytic degreasing is immersed in a passivation solution including dichromic acid and chromium sulfate and a voltage of about 0.5 to 5.0 V is applied for 5 seconds or more.

A process for the surface treatment and/or production of a metal or alloy product including the steps of: a) dulling of a surface of the metal or alloy product and b) electrochemical treatment of the dulled surface of the metal or alloy product, and a metal or alloy product which produced or able to be produced by the process.

This ferritic stainless steel has a predetermined chemical composition, at least one type of oxides of oxides containing 5 mass % or more of Al and oxides containing 5 mass % or more of Si are present on the surface, and, among the oxides present on the surface, the number of oxides having a diameter D of 0.1 μm or more and 2.0 μm or less is 10 or more per 93 μm.sup.2, the diameter D being represented by D=(Dmax+Dmin)/2 where Dmax is the maximum diameter of the oxide on the surface and Dmin is the minimum diameter of the oxide on the surface.

This ferritic stainless steel has a predetermined chemical composition, at least one type of oxides of oxides containing 5 mass % or more of Al and oxides containing 5 mass % or more of Si are present on the surface, and, among the oxides present on the surface, the number of oxides having a diameter D of 0.1 μm or more and 2.0 μm or less is 10 or more per 93 μm.sup.2, the diameter D being represented by D=(Dmax+Dmin)/2 where Dmax is the maximum diameter of the oxide on the surface and Dmin is the minimum diameter of the oxide on the surface.