Thermal Effect in Minimizing Air Entrainment in the 3D Shot Sleeve During Injection Stage of the HPDC Machine

The high pressure die casting (HPDC) process is an important commercial process for the production of complex near net shape metal castings, characterized by low cost and high efficiency. In this process, the thermal effects of molten metal flow in the shot sleeve are a major factor in determining casting surface quality and many internal quality parameters such as porosity. Therefore, promptly evaluate the thermal effect on the injection stage is vital to the quality control and improvement of productivity. The geometric complexity of the die leads to strongly three-dimensional fluid flow with significant free surface fragmentation and splashing. A popular commercially available software package for heat flow simulations and analysis, fluent, is used and employs the volume-of-fluid (VOF) method for tracking interfaces. A 3D multi-fluid flow and heat transfer are performed to simulate the injection stage of liquid aluminum to ensure the minimum air entrapment. Different process parameters were tested and plunger velocity was optimized by using simulation.