How to Quench 6063 Aluminum Profiles on a Press

The 6063 aluminum alloy is the most popular choice for architectural and structural extrusions. To give these profiles their final strength, they must undergo heat treatment. ASTM B807 is the official standard for press quenching, also known as press solution heat treating. This process uses the natural heat of the extrusion press to dissolve alloying elements, saving time and lowering energy costs by skipping a separate heating furnace.

What is ASTM B807 for 6063? It is the standard process rules to cool the 6063 alloy directly after it leaves the extrusion die to achieve structural properties safely and cheaply.

The Three Steps to Press Quench 6063 Aluminum

To follow the ASTM B807 standard for the 6063 alloy, your extrusion line must control three specific phases: exit temperature, cooling speed, and oven aging.

Step 1: Die Exit Temperature

• The Goal: The 6063 alloy must be hot enough when it leaves the press die to keep magnesium and silicon fully dissolved in the metal structure.
• The Numbers: The minimum exit temperature for 6063 aluminum must be at least 500 degrees Celsius (932 degrees Fahrenheit).
• Why it matters: If the profile is too cold when it exits the die, the structural elements will not mix correctly. This leads to weak metal that fails mechanical tests.

Step 2: Cooling Rate (The Quench)

• The Goal: You must cool the hot profile quickly to freeze the dissolved elements in place before they can separate.
• The Method: The 6063 alloy has a very low quench sensitivity. This means you do not need aggressive water tanks. You can use standard forced air or a mild water mist system.
• The Speed: The profile temperature must drop below 200 degrees Celsius within a few minutes after exiting the press.

Crucial Rule: The cooling air or water mist must strike all sides of the 6063 profile evenly. Uneven cooling creates internal stress, which twists and bends long profiles.

Step 3: Artificial Aging

• The Goal: Press quenching alone makes the metal stable but not fully hard. The profiles need thermal baking to reach their final hardness.
• The Process: Place the cooled and straightened profiles into a dedicated aging oven.
• The Settings: Bake the profiles at 175 to 185 degrees Celsius for 4 to 8 hours to create the final strong structure.

Achieving T5 vs. T6 Tempers on 6063 Aluminum

The ASTM B807 standard allows you to produce both T5 and T6 tempers directly from the extrusion press line for the 6063 alloy.

The T5 Temper Process

• Cooling Method: Use standard high-velocity forced air blowers on the run-out table.
• Aging Settings: Bake in the aging oven for 4 to 6 hours at 180 degrees Celsius.
• Result: Excellent shape control, minimal warping, and good structural strength for windows, doors, and frames.

The T6 Temper Process

• Cooling Method: Forced air is often not fast enough for full T6 properties. You must use a water mist system or localized water spray nozzles to speed up the quench.
• Aging Settings: Bake in the aging oven for a longer duration, typically 6 to 8 hours at 175 degrees Celsius (347 degrees Fahrenheit).
• Result: Maximum hardness and mechanical strength for load-bearing structural applications.

Key Parameters for 6063 Press Quenching

Target Temper	Min. Die Exit Temp.	Cooling Method	Aging Temperature	Aging Time
T5 Temper	500 degrees Celsius	Forced Air Blowers	175 – 185 degrees Celsius	4 – 6 Hours
T6 Temper	510 degrees Celsius	Water Mist or Spray	170 – 180 degrees Celsius	6 – 8 Hours

Main Benefits for 6063 Production

• Lower Energy Bills: You do not need to turn on a separate furnace to reheat cold profiles for solution heat treatment.
• Faster Turnaround: Fewer manufacturing steps mean you can pack and ship finished 6063 profiles to customers much quicker.
• Better Straightness: Because 6063 can cool safely with air or mild mist, it suffers less thermal shock and stays straighter than water-plunged alloys.