4. Low-Pressure Casting
Low-pressure die casting (LPDC) refers to the manufacturing process where the molten metal slowly fills the die and solidifies. It relies on the low pressure (0.06-0.15MPa) on the metal surface which is produced by compressed air in the crucible placed above (as the diagram shows).
Low-Pressure Casting Process Diagram

Low-Pressure Casting Advantages
- Good feeding and compact casting structure
- Can create casting parts with big sizes, thin walls, and complex shapes without a riser
- High metal yield rate (95%)
- No pollution and easy-to-implement automated production
- Can be used in various casting molds (such as metal & sand molds) and alloys due to its adjustable pressure and pouring speed
- The metal liquid is stable with no splashing since it is bottom injected, avoiding gas inside and scouring to affect the casting success rate
- Good for creating thin-wall casting parts since it produces dense structure, clear outline, and smooth surface with great mechanical properties
- No feeding riser with improved metal utilization rate (90% – 98%)
5. Centrifugal Casting
Centrifugal casting injects molten metal into a high-speed rotating mold where the molten metal spreads along the inside mold wall and solidifies after cooling to form the casting parts.
With the nature of centrifugal casting being centrifugal motion, it helps fill the mold wall in a radial direction and form the surface of the casting parts.
A cylindrical hole can be obtained naturally without a core.
This manufacturing process removes gas and other inclusions in molten metal with a positive effect on metal crystallization, improving the mechanical properties of the casting parts.
Centrifugal Casting Process Diagram


Centrifugal Casting Advantages
- Good mechanical properties. The slag, gas spot, and other inclusions are concentrated on the inner surface of the casting parts, leaving the inner parts of the components in good condition with no porosity, shrinkage, slag and other defects.
- Doesn’t require a gating system
- No consumption of molten metal at risers
6. Permanent Mold Casting
Permanent mold casting refers to the casting process where molten metal fills the mold by the force of gravity and forms the casting parts after cooling and solidification.
Permanent Mold Casting Process Diagram

Permanent Mold Casting Advantages
- High thermal conductivity and heat capacity with fast cooling
- Compact mechanical structure with high stability (15% higher than sand-casting parts)
- Higher dimensional accuracy with lower surface roughness
- Less dust and harmful gas emissions during manufacturing
7. Vacuum Die Casting
Vacuum die casting is an advanced casting process that can help significantly reduce (if not eliminate) the pores and dissolved gases in the die-casting parts. This is realized by discharging the gas of the mold cavity during the manufacturing process. The vacuum die-casting parts have improved mechanical properties with excellent surface quality.
Vacuum Die Casting Process Diagram

Vacuum Die Casting Advantages
- Greatly reduced porosity
- Good mechanical properties with high hardness* and improved elongation**
* The aluminum-magnesium casting parts produced by vacuum die casting can be processed by welding, heat treatment and other post-processing techniques. Their performance at room temperature has also been noticeably improved.
** The elongation of die-casting parts has been increased from 8% to more than 16%.
Vacuum Die Casting Examples
- AM60B magnesium alloy automobile wheel (produced by die casting on a cold chamber die casting machine)
- AM60B magnesium alloy automobile steering wheel (produced by die casting on a hot chamber die casting machine with a locking force of 2940kN)
8. Squeeze Casting
Squeeze casting is a casting technique where molten metal is solidified under mechanical pressure in closed dies to create casting parts. The manufacturing process is also called liquid die forging.
During the squeeze casting process, high pressure is applied to the material as it cools until it’s formed the desired casting shape after crystallization and solidification.
Squeeze Casting Process Diagram

Squeeze Casting Advantages
- No gating system which produces material waste
- Squeeze casting parts can be heat treated
- Good feeding effect with fine grains and dense structure
- Less cost, longer service life and higher material utilization rate
9. Cavityless Casting
The cavityless casting process adopts an expendable pattern that gets burnt and evaporated after the molten metal is poured into the mold.
Cavityless casting is used to combine paraffin or foam models (in similar sizes and shapes) to cast parts into clusters, which are brushed with refractory paint, dried, and buried in dry quartz sand.
The molten materials are poured into the molds which evaporate after the casting parts are created.
This is a new casting technique that creates the part by forming the model itself after cooling.
Cavityless Casting Process Diagram

Cavityless Casting Advantages
- High precision with no sand core, saving production time
- Flexible in design with no parting surface
- Clean manufacturing process with no pollution
- Less investment and costs
10. Continuous Casting
Continuous casting is an advanced casting method in which the molten metal is poured into a water-cooled mold and the solidified castings are continuously drawn from the other open end. With continuous casting, you can get casting parts at any specific length.
Continuous Casting Process Diagram

Continuous Casting Advantages
- Compact structure and good mechanical properties due to its rapid cooling
- No riser of the gating system on the casting, so no need to cut the head and tail of the casting during rolling, saving time and materials
- Simplified process without modeling process, saving labor costs
- Less production area is required
- Can achieve high mechanization and automation in production
- Improved production efficiency with continuous casting and rolling in ingot casting