Twin Roll Casting of Magnesium Strip at Canmet Materials — Modeling and Experiments

Abstract

At CanmetMATERIALS, a pilot-scale Twin Roll Caster (TRC) facility was used to produce AZ31 magnesium strip and this paper describes the experiments and modeling effort. In the experiments, the effects of cast-strip thickness and roll speed on the surface quality and solidification microstructure of the strip was investigated. The TRC is instrumented with process control sensors and the thermocouple recordings are particularly used to validate the finite volume modeling. The finite-volume-based STAR CCM+ software was used to build a three-dimensional model of the TRC; the computations use implicit time integration. A marked feature of the computations is the inclusion of surface tension of melt, the interaction of the melt with the air, and rotating rolls with varying speed. This paper will also discuss some effort to minimize lateral freezing fronts in the edge of the strip by optimizing the nozzle shape and geometry.