UACJ Cast Technologies

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UACJ's expertise in casting technologies, which is globally recognized, arose through the casting of items such as turbocharger compressor wheels (impellers), which require rigidity and high-dimensional accuracy. We would like to show your company how you can apply UACJ's casting technologies to help you develop products, improve quality and reduce costs.


PRECISION PRSSURE CASTING(PPC) is UACJ original low-pressure casting process using one-piece plaster molds from elastic patterns.


Thin-walled, high-precision, smooth and high-strength Aluminum alloy castings.
Both small-batch production and mass production can be applied.

Design Flexibility

  • Under-cut and/or 3-D curved surface design products can be cast using one-piece plaster molds.
  • Generally, the minimum wall thickness should be 1.5mm. 0.35mm or less may be applied when required (ex. The tips of rotor blades).
  • The fluctuations of blade thickness may be allowed.
  • No cores and inserts can be applied.

Dimension accuracy

Generally, around CT6 can be applied in the PPC cast process.
Stricter standards may be applied when required.

Surface Roughness

Generally, within 18S will be guaranteed, and locally within 12S may be applied in the plaster mold process.

Soundness and Strength

  • Soundness is achieved through the PPC process with chill plates.
  • Strength can be controlled with sound internal structures and heat treatment(ex T4,T5,T6,T7 etc.), when required.

Scope of Application

  • Size: Maximum 100mmx100mmx150mmH or Φ100mmx150mmH
    Larger products may be supplied when required.
  • Volume: From 10 pieces to more than 100 thousands pieces per month. Production volume is flexible.
  • Alloy: Al-Si Alloy(ex.356,A356,354,C355) and Al-Cu Alloy can be supplied.
    Castings by other alloys may be supplied when required.

Comparison of PPC process with other processes

  PPC process Sand Casting Metal Mold casting Die-Casting Lost-wax Cold Forgings
Tolerance(not including the parting lines) CT6 CT8 CT7 CT5 CT6 equivalent IT7-11
Surface roughness Within 18S 40-100S 10-80S Within 12S 6-20S Within 10S
Wall thickness Min. 0.35t Min. 3t Min. 4t 1-7t Min. 1t Min. 0.2t

References: Japan Foundry Engineering Society KANTO website, Japan Die Casting Association website, The Nikkan Kogyo Shimbun, Ltd. website, UACJ internal documents


The most popular application is rotors, such as the compressor wheels(C/W) for turbochargers and superchargers. More than 10 mil UACJ C/Ws are supplied annually throughout the world.
Though the wall thickness of the blade tips is only 0.35mm, the peripheral velocities often exceed the speed of sound.

To “casting compressor wheels” (product information)


The dies for elastic patterns are required.
They are relatively low-cost, and their life is semipermanent as no attacking and/or abrasive materials such as molten metals and sands will be in contact with the dies.