THE DESIGN OF FEED SYSTEMS FOR THIN-WALLED ZINC HIGH-PRESSURE DIE CASTINGS

A number of methods have been devised for the design of feed systems i n high-pressure die castings to optimize their mechanical properties. Most of these result in a decrease in the included gas porosity by hav ing runners which decrease in area along the flow direction. Although the influence of the ingate design on matters such as surface quality of the casting and erosion of the die are well known, the ingate is no t usually a critical part of design for optimizing mechanical properti es. Nevertheless, it is known that the mechanical properties of pressu re die castings made of zinc alloy 3 (Zn-4.1Al-0.05 Mg) can be improve d by controlling ingate size and molten metal injection velocity. In t his article, we describe a method for designing the ingate so as to op timize the mechanical properties.