Abstract: Because strain rate has an main influence on critical strain of shell in the mold, the increase or sudden change of strain rate makes critical strain decrease, the strain rate of shell must be controlled. Considering the shrinkage characteristic of solidified shell in the thin slab continuous casting mold, a new thin slab continuous casting funnel mold is developed. In the new mold, funnel curve curvature varies continuously, the curvature variation is small and constant, and the shell strain rate does not suddenly change. The funnel curve reaches G2 continuity. The expressions of horizontal and vertical curve in funnel area are given. Considering solidified shell shrinkage and deformation, the self-developed computation code is used to construct the funnel curved surface. The stress distribution of wide face shell is solved by a thermo-mechanical coupled model. Compared with import technology, the result indicates that the stress of wide face shell in mold decreases 20%, especially the stress decreases 35% at the area of cracking susceptibility. The possibility of cracking is reduced effectively and the quality of thin slab is improved in the new mold.

Key words: Curvature, Curvature variation rate, Funnel mold, Thin slab continuous casting