Gravity Diecasting, Permanent Mold Casting
Permanent mold castings are suited to high production runs, and are normally larger than pressure diecastings, the maximum weight of these castings is usually about 10 kilograms. Tooling costs are high, but less than those for pressure diecasting. Destructible cores may be used and internal cavities can be fairly complex.
Permanent mold castings are gravity fed with a relatively low pouring rate, either by
hand or by robot. The metal mold produces rapid solidification. Castings produced by the permanent mold method have excellent mechanical properties, are generally sound and hold good dimensional tolerances. Permanent mold castings may be heat treated, which further enhances their mechanical properties. For maximum properties the full heat treatment cycle of a solution treatment, followed by a quench, and natural or artificial aging is used.