Strand surface cracks - the role of abnormally large prior Austenite Grains
Transverse cracks present on the surface of continuously-cast semis prior to rolling often cause undesirable imperfections on rolled product. Such cracks can occur on all types of strand cast product; billets, blooms, slabs, rounds, and beam blanks. Transverse cracks range in severity from those that are short, thin and hard to find on a scaled surface to those that are long, gross and readily apparent. A typical fine transverse crack found on the broadface of a slab after cold machine-scarfing, is shown in Figure 1. Although not a rule, transverse cracks often occur at or near as-cast corners.