Experimental and numerical analysis of flow behavior and particle distribution in A356/SiCp composite casting

Flow behavior and particle distribution in an inverted U-shape A356/SiCp composite casting produced by conventional investment casting were investigated experimentally and numerically. The mold filling process was directly observed by real-time X-ray radiography and the SiCp contents in casting different parts were quantitatively measured and analyzed. Based on the Euler and Lagrangian methods, the flow behavior of composite slurry and the particle distribution were simulated. During mold filling process, eddy flow occurred at gravity part and back flow formed at horizontal part after the gravity part had filled. The predicted results of particle trajectories showed that the flow characteristic of particles were turbulence, laminar, and large eddy flow at anti-gravity, horizontal, and gravity part, respectively. For the particle distribution, the measured and predicted results showed that more particles concentrate in the central section, while fewer particles were present near the surface section along the thickness. Moreover, the particle fractions generally decreased with the increasing distance to the ingate. The simulate results were reasonably suited with experimental data.