Effect of second phase particles and stringers on microstructures after rolling and recrystallization

Second phase particles and particle stringers have strong influences on recrystallized grain structure and alloy performances. In this work, the effects of second phase particles on grain size and grain size distribution in the U-10 wt% Mo (U-10Mo) after hot rolling and annealing were investigated and quantified. The particle volume fraction (PVF), distribution, morphology, size, and the formation of stringers during hot rolling were all considered. The criteria for stringers were determined using the edge-constrained post-necking model. Potts Model simulations of recrystallization were performed on six captured U-10Mo microstructures deformed using Finite Element Modeling (FEM). The stringer volume fraction (SVF) was found to be higher for captured microstructures with higher particle aspect ratios. It was determined from these simulations that the recrystallized grain size decreases with increasing PVF and the variation in grain size increases with increasing SVF. The current study will assist in the optimization of U-10Mo processing parameters to account for the effects of the second phase particles that exist in the alloy.