The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 12, 2007
Filed:
Jun. 04, 2004
Paolo Giordani, Crema, IT;
Dario Negri, Bagnolo Cremasco, IT;
Mauro Rigamonti, Opera, IT;
Henkel Kommanditgesellschaft auf Aktien, Duesseldorf, DE;
Abstract
A process for pickling martensitic or ferritic stainless steel, preferably in the form of wires, tubes or rods, wherein the stainless steel is placed in contact with a pickling solution which has a temperature in the range 15 to 29° C. and contains 50 to 120 g/l of free sulfuric acid, 5 to 40 g/l of free HF and 5 to 40 g/l of Fe(III) ions. Such pickling may be incorporated into a sequential process, wherein the stainless steel is a) subjected to a treatment during which the oxidic coating is applied, preferably sand-blasting or metal-blasting, treatment with a molten salt or treatment with an aqueous permanganate/alkali metal hydroxide solution, b) pickled in accordance with the aforedescribed process, and c) post-treated with a passivating solution.