| The Diffusion Solidification process is a new casting method developed by Langford in the early '70s. The process has not yet been commercialized but it has a number of unique advantages over the conventional casting process. The objective of this research was twofold: The first objective was to establish the kinetics of diffusion solidification by relating the process variables to the SD time and casting quality. The momentum and mass transfer aspects were experimentally studied and compared to theoretical models. The experimental results coupled with theoretical models led to equations quantifying the SD time, rte of SD, macrosegregation limits of SD and effect of gases in the shot region on casting quality. The second objective was to design casting machines for the SD process. The process was shown to be commercially feasible by manufacturing irregular shaped casting in investment molds via the radiative casting machine. The economics of heating SD components (with emphasis to the shot-solid charge) by radiation, induced eddy currents and gas infiltration were studied in terms of heating time and efficiency. Experimental results on th direct heating methods, induction and gas heating, indicated that heating times less than the SD time could be attained, thereby confirming the feasibility of rapid cycle steel casting via the SD process. |
