Aluminum Foundry Heat Treatment Process

Heat Treatment of A356 Aluminum Castings to T5 and T6 Hardness

Our combination of modern heat treatment equipment and experienced aluminum foundry personnel work together to provide the precise temperatures and the quick quench needed for controlled and effective heat treat of our A356 aluminum castings. Through the use of five separate systems, Alcast can provide a variety of options for its customers. The most common processes are T5 and T6 hardness, although many others are possible with our equipment.

Our Heat Treatment Department Contains

  • 2 Bake Out Ovens
  • 3 High Temperature (T6) Bake Out / Heat Treat Ovens
  • 2 High Temperature (T6) Heat Treat Ovens
  • 14 Low Temperature (T5 & Artificial Age) Heat Treat Ovens

T5 Heat Treat Process

T5 heat treatment of our A356 aluminum castings is the simplest option for our castings. They are allowed to naturally cool and are then artificially aged at an elevated temperature in one of our low temperature ovens.

T6 Heat Treat Process

Our T6 heat treatment of A356 aluminum castings offers increase in hardness and other mechanical properties, which is often required for many applications. The T6 heat treat is a 2 step process. The castings are first allowed to cool naturally and are then heated at an elevated temperature in one of our high temperature ovens. After a set period of time the castings are quickly quenched. The castings are then moved to one of our low temperature ovens for the second step of the process.

Standard A356 Aluminum Casting T5 & T6 Hardness Properties

The mechanical properties of our A356 aluminum castings from our permanent mold aluminum foundry can be improved through proper casting design and our heat treatment processes. The properties listed below are standards from the Aluminum Association for A356 alloy aluminum:

TemperUltimate (ksi)Yield (ksi)Elongation PercentageBrinnell Hardness
T525.0————55-85
T637.026.05.070-100

The combination of our proprietary ELECTRO-MAGNETIC, low pressure, bottom fill, permanent mold, A356 aluminum casting process and our heat treatment process will typically provide mechanical properties exceeding the above standards4