Back to results
US 5,344,509 AGranted
Process for prevent the formation of adhesives when annealing steel band
AssigneeMesser Griesheim GmbH
InventorPeter Zylla
Life of this patent
Estimating the term…
Abstract
A process to prevent the formation of adhesives when annealing a steel band having a low carbon content uses an inert gas consisting of nitrogen and hydrogen and includes the phases of heating up, holding time and cooling. The process is characterized in that during the holding time, the steel band is coated by oxidation with a thin coating which is then completely removed by reduction during the cooling phase.
Claims2
Process to prevent adhesion during the annealing of steel billets having a low content of carbon in an inert gas atmosphere consisting of 95% to 99% nitrogen and the rest of hydrogen;
- the process including sequentially heating up, maintaining and cooling off phases, the improvement being in that during the maintaining phase the steel billet is coated in a coating step with a thin covering layer by means of oxidation at temperatures above 600.degree. C. [1112.degree. F.], during the coating step 0.2 to 0.3 grams of CO.sub.2 are added to the inert gas per square meter of the surface of annealing material, and completely removing the covering layer through reduction during the cooling off phase at temperatures below 600.degree. C. [1112.degree. F]
Dependencies are inferred from the claim text.