Quantitative Analysis of Microstructural Evolution in Polycrystalline Metal Matrix with Embedded Second Phase Particle
The ubiquitous motion of grain boundaries is responsible for determining the unique microstructural patterns and stability of polycrystalline materials. By employing the versatile multi-phase field modeling methodology, the role of inert, secondary particles on the dynamics of grain boundaries under conditions of uncooperative migration has been analyzed. Systematic studies have been carried out to understand the influence of various particle shapes on the motion of the grain boundaries with a particular attention put on the interfacial interactions. It is found that the motion of the grain boundaries is impeded by pinning effects exerted by these particles. The ability of the moving boundaries to pass through particles of distinct morphologies is different, with the simulation results showing a big influence of particle alignment and the aspect ratio on the pinning of grain boundaries. The results suggest that elongated and flat type spheroid particles are more likely to preserve the grain structure by reducing coarsening significantly. From the numerical analysis, it is also found that these dispersed particles can lead to abnormal grain coarsening. The results suggest that abnormal coarsening occurs when the second phase particles are densely distributed in a particular region in the matrix.
Phase Field Model, Pinning effect, Second phase particle
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