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The mechanism of morphogenesis in a phase separating concentrated multi-component alloy David N. Seidman, Northwestern University, DMR 0241928. [100]. 3D APT. LKMC1. LKMC2. [110]. [100]. [100]. [100]. [110]. [110]. [110].
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The mechanism of morphogenesis in a phase separating concentrated multi-component alloy David N. Seidman, Northwestern University, DMR 0241928 [100] 3D APT LKMC1 LKMC2 [110] [100] [100] [100] [110] [110] [110] The solute-vacancy binding energies strongly affect the the kinetic correlations among the atomic fluxes, which determine the kinetic pathway of nucleation, growth and coarsening in a Ni-5.24at.%Al-14.24at.%Cr alloy*. LKMC 1 coagulation- coalescence LKMC 2 evaporation- condensation solute-vacancy binding No solute-vacancy binding The combination of lattice kinetic Monte Carlo (LKMC) simulation and diffusion theoryexplains the origin of the morphological features observed in the 3D APT (atom-probe tomographic) phase separating images. The necking between adjacent precipitates results from the overlap of their diffusion fields.The vacancy-solute binding energies areof key importance in determining the kinetic pathway during the early stages of precipitation. Fraction, f, of g’-precipitates interconnected by necks as a function of aging time *Z. MAO, C. SUDBRACK, K. YOON, G. MARTIN AND D. N. SEIDMAN, Nature Materials, 6, 210-217 (2007).