STRESS FORMATION IN SOLIDIFYING BODIES - SOLIDIFICATION IN A ROUND CONTINUOUS-CASTING MOLD

In solidifying bodies, there is no stress-free reference state for the displacements as in normal bodies with fixed dimensions, which are st ress free, in all their volume elements, in the isothermal state prior to cooling or prior to heating. This difficulty has been solved in th e present work by using displacement rates, rather than displacements, and all the other relevant quantities also in time differentiated for m. The equations obtained for the time differentiated quantities are i ntegrated with respect to time to obtain the quantities themselves. Di fferent assumptions on the material behavior have been used, viz, visc oplastic-elastic or purely elastic behavior. The concept was applied t o bodies with cylindrical symmetry and, for the sake of simplicity and clarity, to the state of plane strain. The computational examples ref er to the solidification of steel with 0.6 pct carbon in a round conti nuous casting mold. The calculated stress distributions show compressi ve circumferential stress at the surface of the strand and tensile str ess in the interior of the solid shell. Shrinkage profiles depend main ly on the temperature profile and on the thermal strain data used, and can be approximated by the free shrinkage of the strand surface.