Aluminum 6082 vs 7075: Which Alloy Is Right for Your Use?

If you are struggling to choose aluminum alloy between 6082 and 7075, this article Aluminum 6082 VS 7075 will help you.

The aluminum 6082 and 7075 are two different alloys with different mechanical and chemical properties. 6082 is more of a structural alloy, whereas 7075 is known for its strength, making it feasible for high-stress applications.

In this guide, we are going to learn about the differences between the two alloys.

6082 Aluminum: The Structural Alloy

Aluminum 6082 is a strong alloy mostly used for outdoor structures due to its greater strength. It possesses greater resistance against environmental conditions like moisture and air. Its weldability is impressive, helping constructors build complex structures with ease.

It is used where medium to high strength is needed, like building stronger doors, frames, and bridges. The 6000 series is known for its corrosion resistance properties, so it can bear the extreme environmental conditions very well.

7075: The High-Strength Alloy

Aluminum 7075 is known as one of the strongest commercial alloys. Its high strength makes it a definite choice to be used for high-tech projects like aircraft equipment, etc. It is not commonly found due to its limited use and high prices.

High Zinc and Copper content in aluminum 7075 gives it extra strength. However, the corrosion resistance decreases due to the addition of these elements.

So, a coating of the aluminum layer is required to use it for aerospace and high-stress engineering applications.

Aluminum 6082 vs 7075 in Alloy Properties

Here are a few of the properties for both aluminum 6082 and 7075 alloys.

Chemical Composition

Aluminum 6082 and 7075 have different chemical compositions. The higher content of zinc and copper makes aluminum 7075 a bit stronger, whereas higher Magnesium (Mg) and silicon (Si) bring strength and corrosion resistance in aluminum 6082. Here is a comparison table of both aluminum alloys for their chemical compositions.


Aluminum Alloy	Si	Fe	Cu	Mn	Mg	Cr	Ni	Zn	Ti	Zr	Others in total	Al
	Mass Fraction %
6082	0.7-1.3	≤0.5	≤0.1	0.4-1.0	0.6-1.2	≤0.25	-	≤0.2	≤0.1	-	≤0.15	Remainder
7075	≤0.4	≤0.5	1.2-2.0	≤0.3	2.1-2.9	0.18-0.28	-	5.1-6.1	≤0.2	-	≤0.15	Remainder

Data Source: The Aluminum Association (AA), “International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys”

Mechanical Properties

The mechanical properties, such as tensile strength, yield strength, elongation, hardness, and density, are a few of the properties that help you understand the strengths of both aluminum alloys.

The strengths of these two alloys are quite different. 7075 has strength almost double than that of 6082.

The density of both alloys is good, with almost the same elongation. However, there is a difference in the hardness of the two alloys.

Let’s check out these mechanical properties for each alloy, i.e., 6082 and 7075.

When comparing the mechanical properties between aluminum alloys 6082 and 7075, we must compare them in their most common temper for the same product form.

T6 is the most common temper for alloy 7075. Similarly, T6 for alloy 6082.
Standards such as ASTM and GB/T typically specify guaranteed minimum values, and these minimums can vary depending on forms and dimensions. There is another metric known as a typical value, which represents the average performance of a material under ideal conditions. For this comparison, we will use typical values to provide a more intuitive comparison between the 6082-T6 aluminum and 7075-T6 aluminum.

Data Source: MatWeb, ASM Handbook, or other reliable sources.

Is 7075 stronger than steel?

Light steel is comparatively weaker than 7075. However, the high-end carbon steel is way stronger than aluminum 7075. But, 7075 provides an excellent strength-to-weight ratio, making it a better choice to have rather than using steel.

READ MORE: Steel vs. Aluminum

Corrosion Resistance

6082 Aluminum

The 6000 series is known for its corrosion resistance, making it suitable for marine environments. 6082 is better when it comes to corrosion resistance. The large structures and marine equipment are usually made with this alloy.

7075 Aluminum

The Aluminum 7075 is not as good as 6082 when it comes to resistance against corrosion. It is mostly used when coated with aluminum layers.

The hardness and strength make it a good fit for the aerospace equipment after aluminum coating.

Is it feasible to use 7075 for marine environments?

No, aluminum 7075 is prone to corrosion, making it an unfit choice for marine environments. 6082 is preferred in such environments.

READ MORE: Does Aluminum Corrode? How To Prevent Aluminum Corrosion?

Machinability


Machinability	Aluminum 6082	Aluminum 7075
	Good	Worse

6082 offers good machinability but is not considered as crisp as harder alloys like 7075.
7075 has good machinability. It has good chip breaking properties during cutting because of its hardness. However, compared to 6082, it causes greater wear on cutting tools.

Weldability

6082 Aluminum

Aluminum 6082 is weldable and offers greater ease while building large structures. MIG, TIG, and MMA techniques are used to weld the alloy.

7075 Aluminum

Aluminum 7075 is not weldable. It is prone to cracking if welded, so the strength of the alloy also decreases. So, it is better not to use aluminum 7075 in applications where welding is required.

Heat Treatment

Both aluminum 6082 and 7075 alloys respond well to heat treatments. Heat treatment is performed to change the mechanical properties of the alloys, usually to provide good strength and agility.

6082 Aluminum

6082 is heat treatable and attains better strength after the treatment. However, even after achieving the maximum strength after the heat treatment, the strength doesn’t match aluminum 7075.

7075 Aluminum

Heat treatment for aluminum 7075 provides peak strength and shows improvement against corrosion. It is a better option to have for high-strength applications.

Aluminum 6082 vs 7075 In Applications


	Aluminum 6082	Aluminum 7075
Common Applications	Structural buildings, enclosures, and outdoor uses	Aircraft equipment, especially wings
	Bridges and crane parts	Bicycle Frames and Rims
	Transport frames	High-tech racing car suspensions, wheel hubs, and frames
	Barriers and ship equipment	Firearms and weapons
	General fabrication that requires greater corrosion resistance	Perfect for making bolts, screw, and machining tools

How to use Aluminum 7075 for aircraft if it is prone to corrosion?

Aluminum 7075 is not a good fit to be used alone for aircraft equipment. So, to use it, it needs an extra layer of aluminum coating to protect it from corrosion.

Price Comparison

The price for 7075 is comparatively higher than that of 6082. The alloying elements used in 7075, such as zinc and copper, make its price higher.

On the other hand, 6082 is cheaper than aluminum 7075. It could be the ideal choice due to its medium to high strength and corrosion resistance.

7075 is not commonly used. It is only available for specific super-high-strength applications.

Which Aluminum Alloy Should You Choose?

The use of the alloy is totally dependent on your needs.


Choose Aluminum 6082	Choose Aluminum 7075
Corrosion resistance is the primary need.	A strength-to-weight ratio is needed.
Structural and marine projects are the tasks.	Your applications require high impact and stress.
You are planning to fabricate or weld large structures.	Your applications require high-precision tools or parts.
You are looking for a cost-effective alloy.	It's feasible for you to coat the alloy to protect it.
General fabrication that requires greater corrosion resistance	Aerospace equipment is acquired.

Which Alloy is better?

It depends on your need. If you need good corrosion resistance, you might need to use 6082. If you require greater strength, you need to use 7075. However, if your workpiece requires extrusion or welding, 7075 alloy may not be suitable. So, we cannot simply say that one alloy is better than another.

Still Unsure? Contact Our Experts for a Consultation

FONNOV is an aluminum fabricator and aluminum extrusion manufacturer company providing custom aluminum profiles and standard profiles for general and high-tech applications.

If you are unsure, contact the experts from FONNOV ALUMINIUM to find the best alloys you need for your applications and any consultation you need.

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.