The Heat Flux and the Effects of Mould Shape on Distortion of the Mould in a Thin Slab Caster

Geometrically, there are two kinds of mould to achieve high-speed casting: funnel-shaped and parallel mould. The mould shape and high casting speed lead to higher mould temperatures and shorter mould life than in conventional slab casters. This study analyzes mould wall temperature measured in the plant to determine corresponding heat-flux profiles in thin slab moulds using a Convective Inverse Heat Conduction model. The data is then applied in an elastic-visco-plastic analysis to investigate the deformation of the moulds during service for different mould shapes. Results indicate that model predictions of temperature and distortion during operation match plant observations, with the hot face temperature reaching 440-445˚C and copper plates bending towards the steel, resulting in a maximum outward distortion of about 0.31-0.33 mm. This distortion occurs just above the center of the wide faces and is smaller than the distortion observed in conventional slab moulds. The findings underscore the importance of accurately predicting thermal distortion in continuous casting moulds, as thermal gradients influence the gap size between the solidified shell and the mould, thereby affecting heat transfer and mould life.