Transformation of the Surface Cracks of in Continuously Cast Slabs Made of Low-Alloy Pipe Steels during Hot Rolling

A finite-element mathematical model is developed to describe the transformation of the surface cracks of continuously cast slabs made of low-alloy pipe steels into sheet defects during hot rolling. The transformation of axial, edge, rib, and side cracks of a slab is investigated. It is found that, depending on the deformation conditions, surface cracks on rolling a slab into a thick sheet can close in the first passages under compressive stresses, come to the surface, form folds, twist toward the edge, or completely rolled out.