This guide is going to help you know more details of 2024 vs 6061 aluminum.
When it comes to strength, both aluminum 2024 and 6061 could be the best choices. However, the addition of copper in 2024 aluminum gives extra strength and provides fatigue resistance, which is crucial for aerospace applications.
On the other hand, aluminum 6061 is a strong alloy offering great resistance against corrosion. It helps where corrosion resistance is crucial, especially in marine environments. It is readily available in the market in different shapes. However, 2024 is expensive and only needed when excellent strength is acquired.
2024 vs 6061: A Comprehensive Comparison
Here is a comparison table for you to understand both aluminum 2024 and aluminum 6061.
| Property | Aluminum 2024 | Aluminum 6061 |
| Main Alloying Element | Copper and Magnesium | Magnesium and Silicon |
| Tensile Strength | High | Lower |
| Yield Strength | High | Lower |
| Hardness | Harder | Not as hard as 2024 |
| Fatigue Resistance | Excellent | Good |
| Corrosion Resistance | Poor | Good |
| Weldability | Poor | Excellent |
| Machinability | Excellent | Good |
| Anodizing Response | Poor | Good |
| Cost | Higher | Lower |
Key Differences of Aluminum 2024 and 6061
Here are a few of the key differences between 2024 and 6061. Let’s find out what they are offering.
Chemical Composition
| Aluminum Alloy | Si | Fe | Cu | Mn | Mg | Cr | Ni | Zn | Ti | Zr | Others in total | Al |
| Mass Fraction % | ||||||||||||
| 2024 | ≤0.5 | ≤0.5 | 3.8-4.9 | 0.3-0.9 | 1.2-1.8 | ≤0.1 | - | ≤0.25 | ≤0.15 | - | ≤0.15 | remainder |
| 6061 | 0.4-0.8 | ≤0.7 | 0.15-0.4 | ≤0.15 | 0.8-1.2 | 0.04-0.35 | - | ≤0.25 | ≤0.15 | - | ≤0.15 | remainder |
Data Source: The Aluminum Association (AA), “International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys”
2024 Alloy—Copper’s role in its Strength
3.8-4.9 % addition of copper in 2024 aluminum plays a vital role in its strength as it forms Alâ‚‚Cu, which blocks the dislocation movements. The hardness comes when the dislocation movements are observed, which helps manufacturers build aircraft equipment and wings.
Copper increases the strength but decreases the resistance against corrosion. The promotion of galvanic corrosion due to the copper content reduces the ability of aluminum 2024 to be used for marine environments.
Alclad is helpful while using the 2024 for extreme environments, promoting resistance against corrosion.
6061 Alloy—Addition of Magnesium and Silicon Increases corrosion resistance
Magnesium and Silicon do not promote the galvanic action, making aluminum 6061 stronger and corrosion resistant. The corrosion resistance against the environmental conditions makes it the perfect choice to be used for the marine environments and outdoor use, where moisture could be an issue.
Mechanical Properties
Strength
The strength is measured in two parameters: Yield Strength and Tensile Strength.
The ability of a material to resist the force is called tensile strength. On the other hand, the yield strength of the material tells us about the force that a material can bear before deformation.
Copper content in aluminum 2024 provides extra tensile and yield strengths. On the other hand, 6061 is strong but is not fit for aerospace applications due to its low strength compared to 2024.
Fatigue Resistance
Fatigue resistance is a property of the material to withstand the constant loading and unloading cycles without any breakage or cracks.
The fatigue resistance of aluminum 2024 is excellent compared to 6061.
Copper plays a role in fatigue strength by impeding crack growth in aluminum 2024. Most aircraft joints and wings are made with the help of 2024 alloy, as they need maximum fatigue resistance due to constant loading and unloading.
Machinability Comparison
| Machinability | Aluminum 2024 | Aluminum 6061 |
| Machinability | Better than 6061 | Good |
2024 Aluminum
Aluminum 2024 has better machinability compared to 6061. However, the ductility of aluminum 2024 is affected due to the addition of copper content.
The reduction in ductility creates a cause of fracture in aluminum 2024. As a result, the segmented chips are formed, which are easier to handle with simple cutting tools.
6061 Aluminum
6061 offers good machinability and is good for CNC machining. However, the machinability rating for the 6061 is around 70 % which is lower than that of aluminum 2024 (90 %).
It is harder to break the brittle chips from 6061. You need to use a T6 temper to handle these brittle chips from 6061 for maximum advantages.
For CNC parts, 6061 is an excellent choice due to its brilliant machinability. You can use 2024 as well, where fatigue resistance and strength are needed while managing the corrosion.
Weldability Comparison
| Weldability | Aluminum 2024 | Aluminum 6061 |
| Non-Weldable | Great Weldability |
2024 Aluminum
The 2024 alloy doesn’t offer good weldability as it is a harder alloy compared to 6061.  It is generally considered not suitable for welding due to hot cracking issues. It is why aluminum 2024 is prone to corrosion, and cracks start appearing after a weld.
6061 Aluminum
6061 is an excellent alloy offering brilliant weldability as compared to 2024. 6061 is readily weldable using common methods like TIG/MIG.
The excellent corrosion resistance against moisture, water, and air makes it a perfect choice to use for outdoor structures. It is easier to weld, and smooth surfaces are obtained when handled well.
Corrosion Resistance
2024 Aluminum
2024 has weak corrosion resistance and is used in aerospace applications after cladding. When 2024 is anodized, the copper creates pits by interfering with the anodizing process. This will make an uneven surface, requiring more effort to achieve better finishes.
6061 Aluminum
6061 is less corrosive and offers great weldability. Better corrosion resistance against the environmental conditions makes it a perfect material to be used for large structures, the marine environment, and CNC machining.
The anodizing results are found to be great compared to aluminum 2024. The smoother surfaces are obtained as magnesium and silicon don’t create interference, and an oxide layer is formed.
READ MORE: Does Aluminum Corrode? How To Prevent Aluminum Corrosion?
Price Comparison
| Cost | Aluminum 2024 | Aluminum 6061 |
| Higher | Low Prices as Compared to 2024 | |
| No stock always | Easy to buy in the market |
At Fonnov Aluminium, for example, the cost of extruding 2024T3 aluminum tube is significantly higher than that of 6061T6 aluminum tube.
The prices for 2024 are higher when compared to 6061. The price for 2024 is on the higher side due to its high-tech applications, limited availability and manufacturing cost.
Alumimum 2024 is a specialized alloy and is used for only specific applications. You might not find it off the shelf due to its limited use in daily life.
6061 is cheaper than 2024. It comes in different shapes and has different price brackets.
You can find aluminum 6061 in the market easily due to its great applications and lower prices compared to 2024. 6061 is widely available “off-the-shelf” in various forms of sheets, plates, bars, tubes, and extrusions.
Common Applications: Where Are They Used?
When to Choose 2024 Aluminum
-
Aerospace structural components
-
Precision structural fittings
Aluminum 2024 is a definite favorite for manufacturing aircraft parts. Fuselage and wing skins require fatigue resistance as wing spars and ribs endure constant vibration during flight. The excellent yield strength and fatigue resistance make it an automatic choice for aircraft manufacturers.
Racing vehicles always need less weight and excellent strength. Load-bearing joints, control arms, and suspension parts of the vehicles use aluminum 2024, providing excellent performance.
Aluminum 2024 works great where tight tolerances are observed, making it a perfect choice for machining. Most of the structural fittings require fatigue resistance, to be precise. If fatigue resistance is a concern, aluminum 2024 is a winner.
When to Choose 6061 Aluminum
-
Architectural and structural applications
-
General-purpose machine shop projects
READ MORE:
6061 aluminum is the most widely used alloy in the world, and it is also the most available aluminum alloy on the market. This article The Applications of 6061 will help you learn more details.
In Robotics, 6061 comes in handy to produce arms and mounting plates, making it a perfect choice due to its great machinability and strength. Weldability again facilitates the fabrication of complex geometries and structures in robotics.
The greater thermal conductivity of 6061 allows you to use it for housing, enclosures, and heat sink components. It is easier to tap, drill, and anodize for better aesthetics and durability.
6061 is a definite choice for architectural and structural applications due to its easy weldability and strength. Most of the beams and connectors use aluminum 6061 due to its better finish and durability.
6061 is a perfect choice for machine shops for tooling plates, jigs, and prototypes. The properties, like easy welding and drilling, make it useful for CNC aluminum part projects. There is a huge demand for aluminum 6061 in workshops due to its easy handling.
Conclusion
A short comparison between aluminum 2024 and 6061 gives us the perks of using each alloy.
Aluminum 2024 is stronger and offers an excellent strength-to-weight ratio and fatigue resistance, but it is corrosive. It is the best choice to have for aerospace applications.
On the other hand, 6061 offers corrosion resistance and excellent weldability. The excellent corrosion resistance against the environmental conditions makes it a perfect pick for the marine environments.
Check out FONNOV Aluminum to find the best alloy solutions for you.
About Author
- Xue Song
- Quality Engineer at FONNOV Aluminium Fabrication Plant
Xue Song has been a senior quality engineer at FONNOV Aluminium since 2018. He has more than ten years of experience in aluminum fabrication. Through his articles, Xue hopes to share his practical experiences and thoughts, which may help customers make the most informed decisions on aluminum extrusion and fabrication products.
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