Aluminum remains the best material for use in many different industries. Not only does aluminum have an excellent weight-to-weight ratio, but it also has high strength and is easier to work with. When it comes to making items, 6061 aluminum and 7075 aluminum are the two most common aluminum alloys. While 6061 and 7075 aluminum are similar in some ways, they are also very different in other important ways.
When choosing a material, it is important to understand all of its different properties. It is also important to understand the differences between the different aluminum metals that can be CNC machined. Therefore, the focus of this study is to compare the properties of 7075 and 6061 aluminum. This will help you understand when to use these metals and where to avoid them.
Table of Contents
Understanding 6061 Aluminum Alloy
Many people may ask the question, “What is the most common aluminum alloy in the world?
The answer is 6061 aluminum, which has properties that make it easy to cut and weld. This is mainly due to the fact that it is very strong and its properties can be changed by heating. The main metals that makeup 6061 aluminum are silicon and magnesium. Compared to other materials, silicon and magnesium are resistant to corrosion. This is true even when the surface is braided. If that’s not enough, it can also be anodized in different colors. This can add an extra thin protective layer to it.
Aluminum 6061 is available in many different forms, such as extrusions, sheets, and architectural shapes. Notably, 6063 aluminum is also another popular choice in the 6000 series. In any case, it has a much smoother surface finish than any other metal you can buy. 6063 aluminum is about half as strong as 6061 aluminum. This is because it has much less of the main alloying elements magnesium and silicon. This means it can be used in places where strength isn’t important. For example, roofs and columns that are not load-bearing or artistic structures.
Understanding 7075 Aluminum Alloy
In most cases, 7075 aluminum is used for high-strength tasks. It is mainly used in defense and aerospace applications. It is one of the strongest aluminum alloys in the world because zinc and copper are its main alloying elements. In addition to its excellent mechanical properties, it is also characterized by high strength, toughness, flexibility, and resistance to wear.
Aluminum 7075 is also moderately good at corrosion resistance, anodic oxidation response, and machinability. 7075 grade aluminum is simple to fabricate, but is not suitable for welding. Although it is excellent in many ways, it is not as popular as 6061 aluminum. This is because it is more expensive than other alloys.
What Is the Difference Between 6061 and 7075 Aluminum?
Depending on what you know about aluminum alloys, what is the difference between 6061 and 7075 aluminum?
In this blog post, we will compare them based on some different parameters.
Alloy Series and Chemical Composition
The first difference between 6061 and 7075 aluminum can be seen in their names. 6061 aluminum belongs to class 6000, which is an alloy type. Silicon and magnesium are the main alloys that make up this grade. The 7000 series, on the other hand, includes the 7075 aluminum alloy. Therefore, zinc and copper are the primary alloying elements of 7075 aluminum alloy. 7075 aluminum and 6061 aluminum have the chemical compositions shown in the following table.
| Chemical Elements | 7075 Aluminum | 6061 Aluminum |
| Aluminum (Al) | 90.0% Al | 97.9% Al |
| Magnesium (Mg) | 2.5% Mg | 1.0% Mg |
| Zinc (Zn) | 5.6% Zn | — |
| Silicon (Si) | — | 0.6% Si |
| Chromium (Cr) | 0.23% Cr | 0.2% Cr |
| Copper (Cu) | 1.6% Cu | 0.28% Cu |
Mechanical Properties of 6061 and 7075 Aluminum
Yield Strength
In terms of yield strength, 7075 aluminum alloy is stronger than 6061 aluminum alloy. As a result, 7075 aluminum can withstand greater forces and pressures without changing shape. Due to its chemical composition and heat treatment, 7075 aluminum has a high yield strength. However, 6061 aluminum has a yield strength of 276 MPa and is not as weak as it seems.
Thermal Conductivity
For the most part, aluminum metal transfers heat well. However, 7075 and 6061 aluminum have different thermal conductivity. This is also determined by their chemical composition and the way they are heated. 6061 aluminum has a slightly higher thermal conductivity than 7075 aluminum. Therefore, it is the best choice for heat exchangers where heat dissipation is the main task.
Resistivity
Both 7075 and 6061 aluminum have a low electrical resistivity, which means they have good electrical conductivity. This means that these metals can be used in electrical applications. One difference between 6061 and 7075 aluminum, however, is that 6061 has a much lower resistivity. Because of this, it can transfer energy better than 7075 aluminum.
Elasticity
Elasticity helps to understand how strong an object is and how well it will not deform. It also relates to the stiffness of the material. When elastically deformed, 7075 and 6061 aluminum react in the same way.
Temperature Resistance
Let’s compare the melting points of 7075 t6 and 6061 t6 to see how well they can withstand high temperatures. 7075 aluminum has a melting point of 477-635°C, which is slightly lower than 6061 aluminum, which has a melting point of 582-652°C. This means that 6061 aluminum alloy has a higher melting point than 7075 aluminum. This means that 6061 aluminum alloy can withstand higher temperatures than 7075 aluminum alloy. But you should know that heat treatment is very effective for 7075 aluminum. Heat treatment also results in better dispersion of the metal elements.
Hardness of the Material
The ability of a material to withstand dents, holes, or other deformations depends on its hardness. When pressure is applied to both metals, neither will crack or change shape. However, 7075 aluminum is stronger than 6061 aluminum.
Corrosion Resistance
6061 aluminum does not rust as easily as 7075 aluminum. This is not impossible. Compared to 6061 aluminum alloy, 7075 aluminum alloy has a much higher copper content. Copper is more prone to rusting because it reacts more with its surroundings.
Manufacturing Considerations
In terms of manufacturing processes, 6061 aluminum alloy has an advantage over 7075 aluminum alloy. This is usually because 6061 metal is not as hard or strong when pulled apart. It is easier to machine because of its lower hardness. It is easier to form because it is less strong when stretched. You can join two items together using adhesives, soldering, or brazing. On the other hand, 6061 aluminum can be brazed, while 7075 aluminum cannot.
Applications of 6061 and 7075 Aluminum
Aluminum alloy 6061 and aluminum alloy 7075 are used in some of the same industries. Both alloys are used to make automotive parts, spacecraft parts, and household items. However, they are not used in the same applications.
6061 aluminum alloy is commonly used in the following applications:
- Building products
- Automotive parts
- Electrical appliances
- Bicycle frames
- Connecting pipes
Some common uses for 7075 aluminum alloy include (but are not limited to)：
- Missile components
- Aircraft components
- Shafts and gears
- Fuse components
- Regulating valves
Which Should I Choose Between 6061 Aluminum and 7075 Aluminum?
Choosing between titanium and aluminum may be easy. However, it can be difficult to choose between alloys made from the same metal.
As with many other things, your choice depends on a number of factors. The most important of these is what you want to use it for. Production conditions and price are two other factors.
Aluminum 6061 is a flexible and versatile alloy that can be used for many structural components. It is useful in the following situations:
- Extensive machining is required
- A lot of welding of parts is required
- High corrosion resistance is required
- Machining budgets are tight
However, 7075 aluminum alloy would be more suitable in the following situations:
- A high strength-to-weight ratio relationship is important
- There will be a lot of heat on the equipment
- Stresses are high
- Cost budgets are not so tight
The process of selecting an aluminum alloy is similar to selecting 304 and 316 stainless steel in that both require consideration of the material’s properties and application requirements.
Yonglihao Machinery’s Manufacturing Capabilities
Yonglihao Machinery is the ideal company to work with for your processing. Because we can solve all your problems. At Yonglihao Machinery, we know how important it is to choose the right materials when manufacturing your products. That’s why we use our knowledge to help you choose the right material for your job.
We offer dozens of material options for manufacturing parts., so you can choose the one that’s best for you. We can offer the best rapid prototyping services because we have high standards of production and engineering. All of this is available at a reasonable price and much more.
Summary
The importance of material selection when manufacturing and machining products cannot be overstated. Aluminum is one of the most commonly used metals for manufacturing products. This article has looked at the differences and similarities between 7075 and 6061 aluminum by looking at their particular qualities and how they are used.
As a result, you will need to carefully consider each project to ensure that you pick the right product for your project. Are you having a hard time choosing between 7075 and 6061 aluminum alloys? Then let us help you. Contact Yonglihao Machinery today!
FAQ
Aluminum 6061 vs. 7075: Which is easier to work with?
7075 aluminum is harder and has a higher tensile strength than 6061 aluminum. As a result, 6061 aluminum alloy is easier to form and weld. This means that 6061 aluminum is easier to machine than 7075 aluminum.
What Should I Consider When Choosing Between 6061 and 7075 Aluminum?
There are some basic things you should consider when choosing between 6061 and 7075 aluminum. Your cost budget is important. Therefore, you need to consider the cost of the aluminum. Also important when choosing a aluminum is what you want to use the finished product for. Different manufacturing processes also have different machinability guidelines, so you need to consider these as well.
Can They Be Welded and Formed?
Magnesium and silicon are the main elements in 6061 aluminum, and they make the aluminum easy to weld and shape. 7075 aluminum is not as easy to shape and weld as harder metals with higher zinc content. If desired, 7075 aluminum can be heated and shaped during annealing, or it can be welded into place.
Which Aluminum Reacts Better to Anodizing?
Anodizing works very well on the 6xxx series of alloys. 6061 aluminum is a high-strength structural metal that is very easy to work with. Many shops choose 6061 aluminum when parts need to be hard anodized in many different colors. And 7075 aluminum is a metal alloy with ultra-high strength that is widely used in the aerospace industry. Depending on the metal and process, they can be anodized gray, blue-gray or brown-black.