A356 Aluminum Castings

aluminum investment casting part

A356 is known for being lightweight and high-strength, making it the preferred alloy for engineers designing aluminum castings for the aerospace and defense industries.

A356 Aluminum Properties

The composite makeup of A356 is what makes it a strong, lightweight, and corrosion-resistant alloy. It’s commonly used in structural and high-temperature applications, and is often a must-have material for engineers who need to reduce weight without sacrificing strength. 

Aluminum castings made from A356 aluminum alloy are also far less likely to encounter fractures or fatigue cracks during use, leading to longer service life and lower maintenance, repair, and replacement costs.


AluminumSiliconMagnesiumCopperIronManganeseZincTotal Composition

Due to its alloy composition, A356 can be used as a substitute material for aluminum alloy 6061. As an additional benefit, A356 aluminum reacts well to welds.

A356 Aluminum Alloy Corrosion Resistance (b)

AlloyGeneralStress Corrosion CrackingRelative Machinability (c)Castability (k)Weldability (Arc) (d)
356.0 T52A412
356.0 T62A412


Barron Industries can produce A356 aluminum alloy castings to meet the following specifications:

  • ASTM B618 for general-purpose applications.
  • ASTM B68 for missile, airframe, and other critical applications.
  • SAE AMS-A-21180 (Previously MIL-A-21180) for high-strength aluminum castings for military and defense applications.

To ensure our products meet unique requirements of the aerospace and defense industries and client-provided specifications, we provide rigorous non-destructive testing in our NADCAP-accredited facility.


A356 aluminum is a lightweight alloy known for its high tensile strength, ductility, and exceptional workability. A356 also has excellent corrosion resistance,  good weldability properties, and can withstand high temperatures. This alloy’s hardness level and other mechanical properties can also be improved with T5 and T6 heat treatments.

Applications for Aerospace & Defense

In particular, the aerospace and defense industries use A356 aluminum for a multitude of parts included on aircraft. The impellers inside of a jet engine are made of heat-treated A356 aluminum due to its weight and resistance to corrosion and the elements. 

Think of the temperature extremes that a commercial airliner goes through on a flight. The impellers take in warm air on the ground while the plane is taxing and preparing for rotation (liftoff). While the aircraft is 30,000 feet in the sky, the impellers are taking in air at ambient temperatures as low as -40 Fahrenheit or -50 Fahrenheit. 

Other industries that use A356 include: automotive, nuclear power, machinery, medical, and other commercial industries.

A356 can be commonly found in engine parts, electronic controls housings, airframes, aircraft joints, blowers, jet engine impellers, and other applications requiring a high-strength, low-weight material that can withstand high temperatures and corrosive environments.

Heat Treatments

T5 Heat Treatment Process

The A356 aluminum alloy is heated to a predetermined temperature and naturally air-cooled to set the treatment correctly. The T5 process improves the hardness of A356 aluminum alloy to a Webster Hardness Scale of 8-12.

T6 Heat Treatment Process

The A356 aluminum alloy is heated to a predetermined temperature and instead of being air-cooled, the alloy is water-cooled to forge the steel and prep it for the next step in the process. The forged aluminum is then heated again at a lower temperature for a longer period, thereby completing the process once the alloy is cooled down again naturally. This double-step process produces A356 aluminum alloy at a Webster Hardness Scale of 12-15.

Barron Industries Your A356 Aluminum Casting Foundry

Barron Industries has produced quality A356 aluminum castings for the aerospace and defense industries since 1983. We have won numerous awards and certifications for quality and service, including: Official Approval from GE Aviation and Boeing, NADCAP accreditation for Penetrant Testing, Welding, and Digital Radiography, AS9100D, and Investment Casting Institute Awards for Best Defense and Aerospace Castings.