High-resistance steel strip comprising a temperature homogenisation chamber
AssigneesDrever International S.A., John Cockerill S.A.
InventorsJean-Pierre Crutzen, Lutz Kümmel, Frank Maschler, Michel Renard
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Abstract
Method for thermally treating a scrolling steel strip (5), said method comprising the following steps: heating the strip (5) in a zone for heating with a direct flame (10); temperature homogenisation of the strip (5) in a homogenisation chamber (20) comprising at least one radiant heating tube (25), so as to homogenise the strip (5) in temperature after the passing thereof into the zone for heating with a direct flame (10) of the preceding step; oxidation of the strip (5) in an oxidation chamber (30) with an oxidising atmosphere having an oxygen volume concentration greater than 1%; reduction of the strip (5) in a reduction zone (40).
Claims11
A method for thermally treating a scrolling high-resistance steel strip, said method comprising the following steps:
- a) heating the strip in a zone for heating with a direct flame, the heating step being carried out with an atmosphere having an oxygen volume concentration less than 0.01% by volume;
- b) temperature homogenisation of the strip in a homogenisation chamber comprising at least one radiant heating tube, so as to homogenise the strip in temperature after the passing through the zone for heating with a direct flame, the temperature homogenisation step being carried out with an atmosphere having an oxygen volume concentration less than 0.01% by volume;
- c) after the temperature homogenization of the strip, oxidation of the strip in an oxidation chamber with an oxidizing atmosphere to form an oxide layer on the strip, wherein the temperature homogenisation results in growth of a more homogenous oxide layer thickness over the surface of the strip as compared to a thickness of an oxide layer without the temperature homogenisation;
- d) after the oxidation of the strip, a further thermal treatment step which increases a temperature of the strip and comprising reduction of the strip in a reduction zone to remove the oxide layer.
Dependencies are inferred from the claim text.