A356 Aluminum Castings

Engineers and Tooling manufacturers alike use A356 aluminum castings in their finished pieces for a variety of reasons. Chiefly among them, the big reason is that A356 aluminum castings are fairly lightweight without losing hardly any of their tensile strength. These characteristics make A356 a go-to material for pieces needing weight shaved off of it and to be durable and strong as well. 

A356 Aluminum Properties

The A356 composite makeup in the aluminum casting is made out of a mix of Aluminum. Silicon, Magnesium, Copper, Iron, Manganese, and Zinc. This composite makeup is lightweight and strong and also has resistance to corrosion. A356 Aluminum can also undergo heat treatments to increase hardness properties and other durability metrics which we will cover in detail later on. 

The exact breakdown of components in A356 aluminum alloy is as follows:  

Aluminum – 92.05% 

Silicon – 7% 

Magnesium- 0.35% 

Copper- 0.20% 

Iron- 0.20% 

Manganese- 0.10% 

Zinc- 0.10% 

Total Composition- 100% 

 Due to the alloy composition of A356 aluminum, A356 can be used as a substitute material for aluminum alloy 6061. As an additional benefit, A356 aluminum reacts well to welds (MIG, TIG, etc.). 

Common Industries and Applications for A356 Aluminum

The uniqueness of A356 with its lightweight and strong strength and ductility lends itself to many applications and industries. In particular, the aircraft and aerospace 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 -40F or -50F. 

Other applications and industries that use A356 aluminum castings include: high-velocity blowers, chassis parts for trucks and automobiles, structural framing for space shuttles and aircraft, nuclear power plants, machinery industry, pump components, housings, covers, plates, automobile transmission cases, automobile oil pans, automotive pump bodies, medical industry, tooling, firearms, and others. 

T5 and T6 Heat Treatments

As mentioned above, heat treatments can improve hardness and other compounds in A356 aluminum alloys. These treatments are known as T5 and T6 heat treatments and they both have their advantages and disadvantages. We will cover each heat treatment in detail below. 

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 Defense & Aerospace industries since 1993. We have won numerous awards and certifications for their service and attention to detail. These awards and certifications include: Official Approval from both 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. 

We employ a full spectrum of aluminum casting production including research and design. Barron Industries’ attention to detail and award-winning casting production methods can help any industry in need of A356 aluminum castings.