Effects of Injection Velocity on Distribution of Primary alpha-Phase Particles in Semi-Solid High Pressure Die Casting of JIS AC4CH Aluminum Alloy

摘要

We have previously developed a new injection process with improved fluidity through applying shear stress. In this process, the product is made by injecting a solid-liquid slurry. Therefore, the microstructure of products made by this semi-solid injection process shows the dispersal of the spherical primary alpha-phase particles in the matrix. The primary alpha-phase particles and matrix are formed from the solid phase and liquid phase, respectively, when the slurry is injected. These phases have different properties, and the properties of semi-solid products are thought depend on the distribution of the primary alpha-phase particles. For this reason, semi-solid products have characteristic microstructures.