Influence of the scale formation on a decarburization of the non-oriented electrical steel

The process of the decarburization was examined on the samples of non-oriented electrical steel sheets of laboratory and industrial production with different initial silicon and aluminium content. The annealing in a wet hydrogen atmosphere was performed at the temperature of 840 degrees C. The comparison of results showed that the rate of the decarburization was determined by oxidation of the surface. Scale formation is influenced by solute elements with a higher affinity toward oxygen than that of iron (Al, Si Mn). The kinetics of decarburization and the relationship between scale morphology as well as parameters of the annealing atmosphere were determined.