Developing Banding Microstructures in Directional Solidification of Aluminum Metal Matrix Composites

Solidifying aluminum alloysAluminum alloys, particularly metal matrix compositesMetal matrix composites (MMCs), present an ongoing challenge due to the inherent difficulty in achieving a uniform distribution of ceramic particles within the aluminumAluminum matrix. In this study, we investigate the anomalous phenomenon of particle banding that occurs during directional solidificationDirectional solidification (DS) of an Al-TiC-15wt%Zn composite fabricated through self-propagating high-temperatureHigh-temperature synthesis (SHS). This report presents results from scanning electron microscopy (SEM), allowing us to visualize stitched images along the growth direction of the sample and gain insights into the formationFormation of the banding morphology. Additionally, we initiate a qualitative discussion on the behavior of particles during directional solidificationDirectional solidification. Our findings suggest that an interplay between particle pushing and engulfment, contributes to this uncommon phenomenon. These results and discussions provide valuable insights into the manipulation of particle banding to achieve a targeted distribution of ceramic particles within the aluminumAluminum matrix. This advancement brings us closer to realizing a promising alternative for lightweight composite materials in the automotiveAutomotive and aerospace industries.