The coupling between heat and mass transfer in the Bridgman-Stockbarger growth of non-dilute crystals induces growth rate transients that are longer than those caused by heat transfer alone. The dynamics of the diffusion-controlled growth for thermophysical properties representative of Pb1-xSnxTe and Hg1-xCdxTe are computed from a one-dimensional solidification model which includes melt-crystal phase behavior. Results show that the growth rate response to a step change in pull rate for both systems differs from the exponential decay observed for dilute alloys and that growth rates cannot be inferred from axial segregation data in non-dilute systems due to the dependence of the segregation coefficient on composition.
Bibliographical noteFunding Information:
This research was supported by a grant from the Microgravity Sciences Program of the US National Aeronautic and Space Administration (Ref. No. NSG-7645).
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