DEVELOPMENT OF A THEORY OF THE STRENGTH OF CONTINUOUS-CAST SEMIFINISHED PRODUCTS MADE OF PERITECTIC LOW-ALLOY STEEL

摘要

A mathematical model is presented to describe the thermal stress state of the solidifying skin of the ingot during the continuous casting of peritectic low-carbon steel. A theoretical analysis performed with the use of the proposed model revealed that the magnitude of the tensile stresses in the ingot skin is significantly affected by the increased amount of shrinkage which occurs due to the δ→γ phase transformation. This effect is particularly strong during the intensive heat exchange that takes place near the top edge of the mold. The calculated thermal stresses in the skin are 1.5–2 times greater than the ultimate strength of the steel at temperatures close to the alloy’s solidus, which accounts for the high probability of rupture of the skin.