The Effect of Volume Fraction on γ’ (Ni3Si) Precipitate Coarsening In Ni-Si Alloys
During precipitate coarsening large particles grow at the expense of smaller ones such that the average particle size increases with increasing aging time. Lifshitz and Slyozov1, and Wagner2 published one of the earliest theories of diffusion-controlled coarsening, now known as the LSW theory, wherein the rate of solute transfer from the smaller to the larger particles is controlled by the rate of solute diffusion in the matrix. One of its predictions is the familiar asymptotic rate law 〈r〉3 ≈ kt, where 〈r〉 is the average particle radius and t is the aging time. The rate constant k is related to the material constants of the alloy system.
KeywordsElastic Interaction Increase Aging Time Average Particle Radius Coarsen Rate Constant Elastic Interaction Energy
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