Cost and quality are of primary concern in the manufacture of high performance titanium alloy components (fan, compressor discs, and blades) for jet engine applications. One important step in manufacturing these components is the production of continuously cast titanium ingots via secondary remelting processes such as Vacuum Arc Melting (VAR), Electron Beam Melting (EBM), and Plasma Arc Melting (PAM). During this casting process, macrosegregation defects such as #beta#-flecks can form and deteriorate the ingot quality. Several models of secondary remelt processes have been reported in the literature. The majority of these models focus on modeling the fluid flow and heat transfer using a quasi-steady state approach. This paper presents a fully transient, two-dimensional axisymmetric, continuous casting model that simulates the fluid flow and heat transfer coupled with species transfer during the ingot casting process. The fluid flow computations take into account thermal and solutal buoyancy, Marangoni, electromagnetic, and shear forces which are the primary driving mechanisms in the PAM process. The calculated liquid pool profile and macrosegregation pattern using the proposed model have been validated with available experiments and other model predictions reported in the literautre. As a test case, the model is applied to predict the segregation of Cr, a major #beta#-stabilizing element, in the PAM process. Also, the effect of casting rate on the model predictiosn of pool profile and segregation are studied. Preliminary findings show that regions near the center of the ingot show positive segregation of Cr, whereas a negatively segregated region occurs near the ingotwalls.
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