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Hot tearing is a common solidification defect in both continuous cast steels and foundry shaped castings, which has a significant impact on the quality of the final products. It is a complex phenomenon that involves both the thermal and mechanical conditions and chemical element segregation that evolves during casting process. Over several decades, much effort has been invested into improving our understanding of the conditions required for the occurrence of hot tearing and to relate these conditions with casting parameters, like casting speed in continuous cast process, alloy composition, cooling conditions, etc. This review summarizes the results from previous investigations that have focused on the hot tearing phenomenon of steels, including criteria for hot tearing, experimental methods, and several validated models for different testing methods. The factors that influence hot tearing sensitivity are also reviewed and discussed in the present work. [ABSTRACT FROM AUTHOR]

Hot crack formation in continuously cast steel is significantly influenced by the mechanical properties of the solid shell near its solidus temperature. Herein, a new method to study the high‐temperature mechanical behavior of the solidifying steel shell is introduced. In this method, an apparatus is designed utilizing an electric cylinder that is controlled by a servomotor to apply a specified amount of strain to the solidifying steel shell at a controlled strain rate. A special mold configuration is developed to control the dendrite growth in the direction perpendicular to the applied strain and to ensure that the strain is applied in the region of controlled shell growth. Real‐time load, displacement, and temperature data are monitored by a computer‐assisted data acquisition system. The temperature profile of the casting is predicted by MAGMASOFT and compared with experimental data. The Fourier thermal analysis method is applied to calculate a solid fraction and coupled with the temperature profile to determine the solid shell thickness during the test. The maximum strength at different temperatures for a medium‐carbon steel is determined and compared with that from the submerged split‐chill tensile test and hot tensile tests. [ABSTRACT FROM AUTHOR]