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:
Oct. 29, 1996
Filed:
Aug. 09, 1995
Walter Scheuermann, Bonn, DE;
LOI Thermprocess GmbH, , DE;
Abstract
The present invention relates to a method for annealing metal parts, in particular sheets, in an annealing chamber of an industrial furnace under a protective-gas atmosphere, wherein the annealing comprises a heating phase, a soaking phase and a cooling phase. The annealing chamber is purged during the heating phase with hydrogen or gas rich in hydrogen until the protective gas predominantly contains hydrogen. According to the present invention a purging with an inert gas is performed towards the end of the heating phase to reduce the percentage of hydrogen in the protective gas so that the formation of carbon-containing breakdown products is largely avoided. This prevents the formation of annealing edges during the soaking phase. Towards the end of the soaking phase, a purging with hydrogen or gas rich in hydrogen is performed until the protective gas predominantly contains hydrogen and carbon-containing deposits can be removed.