Thermal and mechanical behavior of copper molds during thin-slab casting (I): Plant trial and mathematical modeling

Abstract

Three-dimensional (3-D) finite-element thermal-stress models have been developed to predict temperature, distortion, and residual stress in the mold of continuous casters of thin steel slabs, comparing both funnel-shaped and parallel molds. The mold shape and high casting speed leads to higher mold temperatures and shorter mold life than in conventional slab casters. This study investigates heat flux and the effects of mold shape on distortion and cracking of the thin-slab mold. In Part I of this two-part article, mold wall temperatures measured in the plant were analyzed to determine the corresponding heat-flux profiles in thin-slab molds. This data was then used in an elastic-visco-plastic analysis to investigate the deformation of the molds in service for the two different mold shapes. The model predictions of temperature and distortion during operation match plant observations. During operation, the hot-face temperature reaches 580 °C and heat flux varies from 7 to 4.5 MW/m2 when casting at 3.6 m/min. The copper plates bend toward the steel, with a maximum outward distortion of about 0.3 mm. This occurs just above the center of the wide faces and is smaller than the distortion of a conventional slab mold.