Brownian Motion Effects on Particle Pushing and Engulfment During Solidification in Metal-Matrix Composites

摘要: Particle pushing and/or engulfment by the moving solidification front (SF) is important for uniform distribution of reinforcement particles in metal-matrix composites (MMCs) synthesized from processing, which can lead to a substantial increase strength composite materials. Previous theoretical models describing interactions between particle and SF predict that large will be engulfed while smaller including nanoparticles (NPs) pushed it. However, there evidence nanocomposites (MMNCs) NPs sometimes distributed throughout material rather than concentrated last regions solidify. To address this disparity, work, an analytical model has been developed account Brownian motion effects. Computer simulations employing over range geometries time steps demonstrate are often pushed. Based on our results, two distinct capture mechanisms were identified: (i) when high random velocity imparted motion, jumps allow overcome repulsion SF, (ii) net force acting insufficient, not accelerated enough outrun advancing SF. This manuscript quantitatively show effect size steady state or critical taken into consideration. The statistical results incorporating effects based Al/Al2O3 MMNC system clearly ultrafine captured cannot predicted any classical deterministic treatments.