Pressure Die Casting
In pressure die casting, metal is melted and forced into steel dies. The metal hardens into the desired shape.
Molten metal is injected into a die cavity through a channel by
movement of a plunger. After a preset solidification time, the plunger
reverses direction, the part is ejected, and the machine is ready for
the next cycle.
Types of Pressure Die Casting.
Hot chamber
This process involves the use of a plunger which traps a certain volume
of molten metal and forces it into the die cavity through a gooseneck
and nozzle. After the metal has solidified in the die cavity, the
plunger is withdrawn, the die opens and the casting is ejected. Metals
having low melting points such as Zinc, copper, magnesium and lead are
cast using Hot chamber die casting.
Cold chamber
In this process molten metal is poured into the injection cylinder
manually by a hand ladle or by an automatic ladle. The metal is forced
into the die cavity at high pressures. High melting point alloys of
aluminum and copper are normally cast using cold chamber die casting.
Possible Pressure Die Casting Shapes
A wide variety of complex 3D shapes.
Example Pressure Die Casting Parts
Engine blocks, bushings, flywheels, levers, gears, automotive, aerospace, medical, appliances, toys and many more.
Advantages of Pressure Die Casting
Parts without any joints
can be made eliminating other processes such as welding and fastening.
Integral fastening elements such as bosses and studs can be included.
Good dimensional accuracy and detail. No further machining required
usually. Low cost.
Specifications for Pressure Die Casting
- Material - Nonferrous alloys that have low melting points: aluminum, zinc, magnesium, copper, lead, tin, silver.
- Alternative machines - Mill 3-Axis, other casting methods.
- Tooling - Requires custom tooling in shape of part.
- Reducing costs - Minimize size, complexity and material volume.
Pressure Die Casting Notes
Parting line is the location where the two mold halves meet. Ejector
pins are small cylinders that push the part out of the mold. Some
flashing will occur at parting line. Coarse external threads on parts
can be formed. Varying textures can be manufactured.
