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:
Feb. 18, 2014
Filed:
Dec. 02, 2005
Ronny Leuschner, Dortmund, DE;
Manfred Meurer, Rheinberg, DE;
Wilhelm Warnecke, Hamminkeln, DE;
Sabine Zeizinger, Mülheim, DE;
Gernot Nothacker, Dortmund, DE;
Michael Ullmann, Bochum, DE;
Norbert Schaffrath, Hamm, DE;
Ronny Leuschner, Dortmund, DE;
Manfred Meurer, Rheinberg, DE;
Wilhelm Warnecke, Hamminkeln, DE;
Sabine Zeizinger, Mülheim, DE;
Gernot Nothacker, Dortmund, DE;
Michael Ullmann, Bochum, DE;
Norbert Schaffrath, Hamm, DE;
ThyssenKrupp Steel AG, Duisburg, DE;
Abstract
A process for melt dip coating a strip of high-tensile steel with alloy constituents including zinc and/or aluminum includes the following steps. The strip is heated in a continuous furnace initially in a reductive atmosphere to a temperature of approximately 650° C., at which the alloy constituents diffuse to the surface in small amounts. The surface, consisting predominantly of pure iron, is converted into an iron oxide layer by a short heat treatment at a temperature of up to 750° C. in a reaction chamber which is integrated in a continuous furnace and has an oxidizing atmosphere. In a subsequent annealing treatment at a higher temperature in a reductive atmosphere, this iron oxide layer prevents the alloy constituents from diffusing to the surface. In the reductive atmosphere, the iron oxide layer is converted into a pure iron layer to which the zinc and/or aluminum are applied in the molten bath with optimum adhesion.