Gravity Die Casting

Gravity die casting:
Casting in metallic permanent moulds (lasting moulds)

Gravity die casting (permanent mould) is different from sand casting (lost mould) in terms of thermal physics in that the metallic moulding material with its high thermal conductivity causes the melt to
cool faster as it solidifies. The short solidification time results in a fine-grained, dense structure which has a positive effect on the mechanical properties of the castings.

Example: Brass fixtures impermeable to gases and liquids

Additional benefits of gravity die casting over sand casting:

• Higher dimensional accuracy and dimensional consistency (reduced machining allowances)
• Better reproduction of contours and surfaces by the metallic mould

Note: The metallic permanent mould is impermeable to gases, so that mould venting problems may occur:
The melt cannot fill the mould cavity entirely and gas pockets may form more often.

Classification by fields of application

Light metal gravity die casting

Aluminium and magnesium alloys

Heavy metal gravity die casting Brass alloys

Cast iron gravity die casting

Near-eutectic and hypereutectic composition of cast iron

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