FIELD: metallurgy.
SUBSTANCE: procedure consists in processing strip in at least two sections arranged successively in direction of strip motion including section of heating and temperature conditioning wherein strip is heated and then conditioned at specified temperature of annealing in oxidising atmosphere, and section of cooling. Iron oxide present in an oxidised layer is subjected to complete reduction to metal iron in reduction atmosphere. The sections are divided with usual air sluice. Also, oxidising atmosphere is at least partially separated from reduction atmosphere maintaining controlled contents of oxygen in the section of heating and temperature conditioning at a level of from 50 to 1000 shares per million and here is maintained controlled contents of hydrogen in the section of cooling and transfer at a level of less, than 4 %, preferably less, than 0.5 %.
EFFECT: production of high strength steel less subjected to brittleness, with good adhesion and wettability without separation of heating section from section of conditioning at reduced contents of hydrogen in zone of heating and conditioning.
12 cl
Authors
Dates
2011-08-20—Published
2007-03-13—Filed