*7.5. The Temperature of the Molten Metal at the Melt*/*Air Interface*

The hydraulic jump on the inclined refractory plane could substantially degrade the surface quality of the cast product, owing to the generation of free surface waves/discontinuities [14]. As per the numerical simulations, the temperature over of the melt/air interface is above the liquidus for a considerable distance, as shown in Figures 11 and 12, even when considering perfect contact of molten metal with the moving belt, which is held constant at 300 K, by the cooling water under the belt. The experimental casting of the AA6111 alloy strip was in accord with numerical simulation predictions, in which the melt/air interface with the belt was observed to be in a liquid state for approximately the first meter along the moving belt. In this way, any molten metal surface discontinuities had enough time to settle down by the damping forces generated, before final solidification.

**Figure 11.** The predicted temperature distribution along the top and bottom faces of the strip along the casting direction.

**Figure 12.** Contour of molten metal temperature in contact with (**a**) the moving belt and (**b**) the molten metal/air interface.
