Product Considerations

Some factors have an influence in all of the processes and have to be discussed further. The factors include

• Size
• Shape complexity
• Tolerances
• Production volume

Size

There are limits on the size of parts that might be processed. The minimum is frequently dictated by physical constraints. For instance, surface tension and freezing of a molten metal limit the smallest size of a mold cavity that may be filled. The minimum may be reduced but not eliminated by filling under pressure; the minimum is different for different alloys. Radically different techniques mostly depend on methods utilized for making semiconductor devices, push the limit much lower (nanotechnology). The maximum is more frequently set by the largest size of equipment available, although there can also be other physical limitations. For instance, the size of hot impression die for forgings or injection molded plastic parts is restricted by the largest press available, while the thickness of the plastic part is restricted by loss of shape because of shrinkage.