THE MECHANISM OF THE INTERNAL OXIDATION LAYER ALONG THE SURFACE CRACKON THE SLAB

When surface cracks on continuous casted slab were observed by a micro scope, internal oxidation layers were sometimes present along the crac ks. These layers that were called subscales were paid attention. The s ubscale was formed in steam atmosphere in laboratory for considering o f the generated mechanism of the surface crack. The results are summar ized as follows, (1)The subscale was the internal oxidation layer wher e the generated rate of scale was greatly reduced. (2)The thickness of the subscale depended on the temperature and the time, and that was c alculated by the internal oxidation theory. (3)The type and the diamet er of particles in the subscale also depended on the temperature. (4)T herefore, the surface crack formed temperature and position in the con tinuous easter were able to decide by the observation of the subscale.