Experimental and numerical study of heat transfer and solidification of molten metal in contact with a cold substrate

his work addresses two important issues of rapid solidification of molten metal quenched on a cold substrate: the numerical modeling of non-equilibrium rapid solidification and the experimental study of the interfacial heat transfer between the solidifying metal and the substrate. The non-equilibrium kinetics of solidification were introduced in traditional heat transfer and fluid flow models in order to simulate the rapid solidification processes such as splat cooling and planar flow melt-spinning. Efficient numerical schemes and techniques were also developed in order to solve the resulting moving boundary problems with complicated boundary conditions at the moving solid/liquid interface. The model could thus be used to calculate some typical non-equilibrium solidification phenomena such as recalescence and solute trapping. The model was also used to investigate the counteraction of fluid flow, heat transfer, mass diffusion, and non-equilibrium kinetics in splat cooling and planar flow melt-spinning.;Two experimental systems were constructed to estimate quantitatively the interfacial heat transfer coefficient (h) in splat cooling: one for a low-melting temperature metal (tin) and one for high-melting temperature metals (nickel and copper). Both inverse technique and temperature matching technique were used to estimate h from the measured temperature history of the splat. A high h (ranging from...