Permanent Mould Casting and Die Casting Flashcards
1
Q
What are the steps in the permanent mould casting process?
A
- Mold preparation (preheating & ceramic coating).
- Mold assembly (cores inserted, halves clamped).
- Pouring molten metal into the mold.
- Cooling for solidification.
- Mold opening and casting removal.
- Trimming excess material.
2
Q
What materials are used for permanent mould casting?
A
- Fine-grained grey cast iron (common).
- Alloy cast iron, C20 steel, alloy steels for large parts.
- Graphite moulds for small-volume production.
- Metal or sand cores (semi-permanent moulding).
3
Q
What are the advantages of permanent mould casting?
A
- Fine-grain casting with superior mechanical properties.
- Excellent surface finish.
- Closed dimensional tolerances.
- Economical for large-scale production.
- Small core holes possible.
4
Q
What are the limitations of permanent mould casting?
A
- Limited maximum casting size.
- High die cost.
- Not all materials are suitable.
5
Q
What are the applications of permanent mould casting?
A
- Automobile pistons
- Stators
- Gear blanks
- Connecting rods
- Cylinder blocks
- Aircraft fittings
6
Q
What is die casting?
A
A process where molten metal is injected at high pressure into a metallic die to produce narrow sections, complex shapes, and fine surface details.
7
Q
What are the types of die casting machines?
A
- Hot-chamber die casting machine.
- Cold-chamber die casting machine.
8
Q
What are some applications of hot and cold chamber die casting?
A
- Carburetors
- Crank cases
- Scooter and motorcycle parts
- Zip fasteners
- Decorative items
9
Q
What is vacuum die casting?
A
- Evacuates air from the die to reduce porosity.
- Produces parts with thin walls (1 to 12 mm).
- Used for aluminum and magnesium-based alloys.
10
Q
What are the benefits of vacuum die casting?
A
- Decreases fill rate.
- No porosity in parts.
- Solidifies before exposure to air.
