THERMO-MECHANICAL ANALYSIS OF A COPPER MOULD FOR CONTINUOUS CASTING OF STEEL

Abstract

This work deals with the thermo-mechanical analysis of a copper mould. In the continuous casting process molten steel flows through a water-cooled mould which induces the solidification of the outer shell. The inner part of the mould undergoes a huge thermal flux and large temperature gradients develop across the copper inducing high stress and plastic deformation, especially in the region close to the meniscus. After the operating period, a cooling to room temperature induces residual stresses which may increase with repeated thermal cycling over a campaign. Another source of cyclic thermal loading during operative condition is represented by the fluctuation of melt metal level into copper mould, with a resulting variation of the temperature peak on the surface of the mould. In this work the structural behaviour of the mould under thermal loading condition is analyzed adopting a three-dimensional finite-element model, with the aim of performing an accurate evaluation of stress and strain levels. An analytical structural model is then developed with the aim of performing a sensibility analysis in the design phase. A simplified thermal fatigue approach has also been followed, in order to gain insights into cyclic behaviour and improve mould life.