Effect of Geometry Structure on Thermal Stress Evolution in Steel Ingot Molds: A Numerical Simulation Study

A thermal–mechanical coupling model is established via ProCAST software, and the dynamic interfacial heat transfer coefficient between the ingot and the mold is determined on the basis of measured data and an inverse calculation model. A systematic study of the influence of the geometric parameters of a mold on the evolution mechanism that governs mold thermal stress reveals that the temperature gradient is the fundamental driving force of thermal stress. The maximum temperature gradient between the inner and outer mold walls occurs at 400 s after pouring, triggering peak tensile stress on the outer wall and peak compressive stress on the inner wall. Parametric simulations demonstrate that increasing the mold wall thickness from 110 to 150 mm reduces the peak tensile stress on the outer wall by 17%, delays the occurrence time of peak stress, and suppresses deformation. Increasing the mold corner radius from 0 to 100 mm effectively eliminates stress concentration in the mid‐upper region, thereby reducing the proportion of the hazardous area exceeding the allowable stress of 200 MPa to almost 0. Increasing the bottom fillet radius from 0 to 150 mm yields a significant 61% reduction in the peak compressive stress on the inner wall.