While many aluminum alloys exist, 6061 aluminum plate is often called the "workhorse" alloy for good reason. For engineers, machinists, and fabricators, it is the most recognized and widely used structural aluminum. Its popularity comes from a superior balance of strength, workability, corrosion resistance, and value.
At GNEE, we supply high-quality 6061 aluminum plate in its two most common tempers: T6 and T4. Understanding the differences is key to selecting the right material for your application's success. This guide provides the core information you need to make the right choice.
Key Differences: 6061-T6 vs. 6061-T4 Aluminum Plate
The primary difference between T6 and T4 tempers lies in how they are heat-treated, which directly impacts their mechanical properties.
- 6061-T6 Aluminum Plate: This temper is artificially aged. After solution heat treatment, the plate is heated in a furnace at a controlled temperature (around 350°F or 177°C). This process significantly increases its strength and hardness.
- 6061-T4 Aluminum Plate: This temper is naturally aged. After solution heat treatment, the plate is allowed to age at room temperature. This results in a softer, more ductile material compared to T6.
Mechanical Properties Comparison: 6061-T6 vs. 6061-T4 Aluminum Plate
The artificial aging process gives the 6061-T6 temper a clear advantage in strength and hardness, which is critical for structural and load-bearing applications.
| Property | 6061-T6 Aluminum Plate | 6061-T4 Aluminum Plate | Unit |
| Ultimate Tensile Strength | 45,000 (310) | 35,000 (241) | psi (MPa) |
| Yield Strength | 40,000 (276) | 21,000 (145) | psi (MPa) |
| Brinell Hardness | 95 | 65 | - |
| Elongation at Break | 12-17% | 20-25% | - |
Note: Values are typical. T6 offers nearly double the yield strength, while T4 offers significantly better elongation, indicating higher formability.
When to Choose 6061-T4 vs. 6061-T6 Aluminum Plate
Here's how to decide which temper is right for your project:
- Choose 6061-T4 if your priority is forming. Because it is softer and has higher ductility (elongation), T4 plate is much easier to bend, form, or deep draw without cracking. It's the ideal choice for parts with complex shapes that need to be created through cold forming.
- Choose 6061-T6 if your priority is maximum strength. For most structural applications like base plates, support brackets, or machine parts, the high tensile and yield strength of T6 is required. It provides better resistance to deformation under load. It is less formable and may crack if bent to a tight radius.
By far, 6061-T6 is the more commonly used temper due to its excellent strength-to-weight ratio.
Workability: Machining and Welding 6061 Aluminum Plate
One of the greatest advantages of 6061 aluminum is its excellent workability.
- Machinability: 6061 aluminum plate is one of the best metals for CNC machining. It produces good, consistent chip formation, allows for high cutting speeds, and results in a great surface finish with minimal difficulty. Both T6 and T4 tempers machine very well.
- Weldability: 6061 has good weldability, but with one important rule: always use a filler metal. Welding 6061 without a filler wire often causes heat cracking in the weld zone. For best results, use a 4043 or 5356 filler wire. The heat of welding will reduce the strength in the area around the weld, which must be considered during the design phase.
Common Applications for GNEE 6061 Aluminum Plate
The combination of strength, light weight, and workability makes 6061 aluminum plate a top choice across many industries:
- Structural & Architectural: Mezzanines, platforms, base plates, bridge railings, and building panels.
- Automotive & Transportation: Truck and trailer frames, ambulance bodies, rail coaches, and custom car parts like intake manifolds.
- Marine: Boat hulls, docks, and other marine hardware, especially in the 6061-T651 temper for its stress-corrosion resistance.
- Aerospace: Light aircraft fuselages, wings, and support structures.
- General Manufacturing: Heat sinks, electrical fittings, fasteners, and machine components.
Get the Right 6061 Aluminum Plate for Your Specs
Choosing between 6061-T6 and 6061-T4 comes down to the specific demands of your project-strength versus formability. Overall, 6061 aluminum plate from GNEE offers a reliable, cost-effective, and highly versatile material solution.
To ensure your project's success, it's critical to select the correct temper and thickness. Contact GNEE today to speak with our technical experts. We can help you select the ideal 6061 aluminum plate for your application and provide a competitive quote.
