Numerical and experimental research on solidification of T2 copper alloy during the twin-roll casting

Based on CAFE theory and KGT model, the twin-roll strip casting mathematical model was established to solve the dendrite growth and solidification of T2 copper alloy in the molten pool. The influence mechanism of casting temperature, heat transfer, and other technological conditions on the microstructure of strip was analyzed. The results showed that the liquid metal formed 35 µm chilling layer after touching the rollers, and the layer was consisted of a high number of small and equiaxed crystals. Then some grains would appear close to the newly chilling layer, and grow toward the core of molten pool competitively. The dominant grains mainly grew along the 〈001〉 orientation into columnar crystals, and the rest grains that grew out of alignment were eliminated gradually. The number of grains declined, and the radius of columnar grains became coarsening. The Kiss point is a key factor for solidification structure, and the lower location of the Kiss point could limit the growth spaces of columnar crystals, which refined the grains.