Search

Increasing the J-factor for atomized flow is expected to reduce porosity in high-pressure die casting (HPDC) products. Casting experiments were conducted to confirm changes in the amount of porosity in two parts of a piston and a wheel with increasing J-factor. As a result, the amount of porosity was reduced in the piston, but increased in the wheel under high J-factor conditions. To clarify the mechanism, a multiphase flow analysis system was developed to calculate turbulent flow using large eddy simulation. The developed system visualizes the state of small voids and vortex structures in molten metal during HPDC. In the piston, the formation of vortex tubes from the thick parts to the overflow promoted void discharge and reduced the number of voids in the thick parts. In the wheel, voids formed by the vortices in the hub part were transferred to the rim part, which is the final filling area, resulting in an increase in voids. From these results, it was possible to clarify the process from the generation to discharge of voids in molten metal flow by analyzing the microscopic state of atomized flow in the die cavity. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s40962-023-01015-8. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. [Extracted from the article]