ABSTRACT
The die-casting process, also called pressure die casting, is a molding process in which molten metal is injected under high pressure into cavities in reusable steel molds, called dies, and held under pressure during solidification. In principle, the process is identical to injection molding with a different class of materials. Die casting can, in fact, produce parts that have identical geometries to injection-molded ones. The reverse is also true, and much of the increase in the use of injection molding since the mid-1980s has been a substitute for part types that were previously die cast. In many cases, this has been a wise substitution, resulting in decreased parts costs. However, for structural parts, particularly those for which thick-wall injection moldings are required, die casting can often be the better selection. The analysis of die-casting costs in this chapter closely parallels the early costing procedure for injection molding given in Chapter 8. This is intended to allow comparisons of the two processes to be made with a minimum of redundant effort. The chapter includes information on the die-casting process, casting materials, equipment performance, and die construction sufficient to understand the factors that influence material and manufacturing cost. The chapter ends with basic design principles that naturally follow from the evaluations of cost drivers in the process. Readers wishing to study the die-casting process further may begin with suggested further reading [1-3] under the reference section.
