Alluminium killed steels are susceptible to the formation of surface cracks during continuous casting. Small deformations which appear, e.g., during the straightening of the curved strand, may lead to the formation of small, intercrystalline surface cracks in the temperature range between 750°C and 1000°C. To study the formation of these cracks, three different mechanical testing methods were applied at mechanical and thermal conditions which are similar to those during continuous casting. These tests are defined as Gleeble-, Beta-, and Dipping-bath tests. The fracture surfaces of the tested samples were studied in detail using the scanning electron microscope. The primary aim of the work was the classification of the fracture modes as a function of the tested steel grades, the temperature, and the different process parameters of the three testing methods.