Different Aluminum Alloys: 6061 vs 7075 Aluminum vs Others

Due to its high strength to weight ratio and appropriateness for a variety of manufacturing uses, aluminum is a popular metal. There are numerous aluminum alloys available for CNC machining, CNC milling, CNC turning, welding, brazing, casting, stamping, forging, and laser cutting. Aluminum is a material that is frequently used in a variety of industries. Aluminum is used in many different industries, including the automotive, aerospace, and medical sectors, because to its versatility.

To help you choose the ideal material for your upcoming project, continue reading to learn about some of the most popular aluminum alloys and typical applications.The aluminum alloys covered below are all great options for CNC machining, and there are many other uses for each alloy outside those that are stated.

6061-T6 Aluminum

6061-T6 aluminum is a form of 6061 aluminum that has undergone a process of precipitation hardening. 6061 aluminum itself is a highly versatile and widely used alloy that can be heat treated. The primary alloying elements in 6061 aluminum are silicon and magnesium. Silicon serves to lower the material’s melting point and enhance its fluidity, while magnesium contributes to increased strength and hardness.

The “T6” designation indicates the temper of the 6061 aluminum material after undergoing precipitation hardening to boost its hardness. The ‘T’ in “T6” stands for thermal tempering, which involves a solution heat treatment (above 900°F), followed by quenching in water, and then aging at a lower temperature (around 300°F) for several hours.

Advantages of 6061-T6 aluminum:

• High strength relative to its low density
• Excellent resistance to corrosion
• Machinability
• Compatibility with paint and finishes
• Ability to be joined through various methods

Disadvantages of 6061-T6 aluminum:

• Experiences a reduction in strength when exposed to high temperatures
• Welding requires skill and experience
• Susceptible to cracking (brittle fracturing) when subjected to bending
• Lower fatigue strength

Common applications for 6061-T6 aluminum:

• Consumer products such as cabinet hardware
• High-strength automotive components
• Parts in the electronics industry, including connectors and fittings
• Components for valves
• Bicycle frames
• Fittings for the aerospace industry
• Pressure vessels
• Hydraulic systems
• Components for the marine industry, including fittings and bodies
• Frames for automotive or locomotive vehicles
• Use in commercial property construction
• Structural components in infrastructure, such as bridges and other architectural structures.

7075-T6 Aluminum

7075-T6 aluminum is a precipitation-hardened variant of 7075 aluminum that shares the T6 temper designation. The primary alloying element in 7075 aluminum is zinc, endowing it with remarkable strength, comparable to steel alloys. It is widely recognized as one of the strongest commercially available aluminum alloys.

Notably, 7075-T6 stands out not only for its overall strength but also for possessing the highest shear strength among the alloys discussed here. This exceptional strength has earned 7075 aluminum the moniker “aircraft-grade” or “aerospace aluminum.” However, this heightened strength comes at the expense of reduced corrosion resistance when compared to less robust aluminum alloys.

Advantages of 7075-T6 aluminum:

• Exceptionally high tensile and shear strength
• Compatibility with paint and finishes
• Formability
• Good fatigue resistance

Disadvantages of 7075-T6 aluminum:

• Elevated cost
• Diminished corrosion resistance
• Moderate machinability, demanding precision and expertise

Common applications for 7075-T6 aluminum:

• Aerospace applications, including frames and structural components
• Bicycle frames
• Tooling
• Gears
• Structural parts for marine and automotive industries
• Plastic injection molds

7050 Aluminum

7050 aluminum is renowned for its high strength and outstanding resistance to exfoliation corrosion, a form of intergranular corrosion that targets the metal at or near its grain boundaries. In addition to its robustness, 7050 aluminum exhibits impressive toughness and fatigue resistance.

This aluminum alloy primarily consists of aluminum, zinc, copper, and magnesium, mirroring the approach of other alloys where zinc enhances strength and magnesium bolsters hardness. The inclusion of copper not only strengthens the alloy but also facilitates the process of precipitation hardening.

Advantages of 7050 aluminum:

• Heat-treatable
• High fracture toughness
• Exceptional strength
• Superb resistance to stress-corrosion cracking, including exfoliation corrosion
• Amenable to machining and forming, even in thicker sections

Disadvantages of 7050 aluminum:

• Not well-suited for welding, as the weld joints exhibit lower strength compared to 7075 aluminum
• Lower electrical conductivity

Common applications for 7050 aluminum:

• Structural components in the aerospace industry
• Equipment for rock climbing
• Various components in bicycle construction

2024 Aluminum

2024 aluminum is a cost-effective and versatile aluminum alloy, albeit somewhat weaker compared to some counterparts in this compilation. It stands out for its good machinability, workability, and ease of finishing. Its primary alloying elements are copper and magnesium, imparting strength and hardness to the material.

What sets 2024 aluminum apart is its notable strength-to-weight ratio and its amenability to heat treatment. However, its elevated copper content does diminish its resistance to corrosion. Consequently, 2024 aluminum is often employed as a clad sheet, with a different aluminum alloy or an alternative metal exposed to the environment to mitigate this reduced corrosion resistance.

Advantages of 2024 aluminum:

• Heat-treatable
• Formable and easy to machine
• High strength
• Durable, boasting a strong resistance to fatigue

Disadvantages of 2024 aluminum:

• Reduced corrosion resistance
• Limited weldability, primarily through friction welding

Common applications for 2024 aluminum:

• Automotive wheels
• Aircraft structural components, including skins
• Gears
• Engine components such as pistons and cylinders
• Fasteners

5052 Aluminum

5052 aluminum is a material prized for its favorable workability and electrical conductivity, rendering it a versatile choice for a wide array of applications. Although it exhibits high fatigue strength, its tensile and shear strength are comparatively lower when juxtaposed with other aluminum alloys.

Advantages of 5052 aluminum:

• Machinable and easily workable
• Exceptional resistance to corrosion
• Weldable
• High fatigue strength

Disadvantages of 5052 aluminum:

• Reduced tensile and shear strength
• Hardening achievable solely through cold working

Common applications for 5052 aluminum:

• Aerospace and automotive applications, including fuel and oil lines
• Sheet metal
• Lighting fixtures
• Wiring
• Components in the marine industry
• Consumer electronics such as computers and televisions

6063 Aluminum

6063 aluminum is a composition primarily consisting of aluminum, silicon, and magnesium. The silicon content of 6063 aluminum makes it particularly well-suited for extrusions and vacuum brazing, given its lower melting point and the ability for the braze alloy to penetrate grain boundaries effectively at the appropriate temperature.

Despite the addition of magnesium, 6063 aluminum is ideal for applications requiring moderate strength without exposure to high temperatures. This alloy’s versatility extends to easy forming into intricate shapes, and its high resistance to corrosion ensures a lasting luster over its operational lifespan.

Advantages of 6063 aluminum:

• Presents a smooth, lustrous appearance
• Amenable to painting and readily accepts various finishes
• Exhibits favorable metal joining properties, including welding and brazing
• Capable of heat treatment
• Suitable for complex geometries
• Boasts high corrosion resistance

Disadvantages of 6063 aluminum:

• Offers lower strength
• Not easily machinable

Common applications for 6063 aluminum:

• Piping
• Railing systems
• Heat exchangers
• Decorative items such as furniture
• Electrical conduit
• Architectural components for both commercial and residential settings, including window frames

Begin Your Next Project With Us

You now understand why aluminum alloys—low density, high strength, and high corrosion resistance—are a fantastic option for CNC machined parts. The question is, how can you choose the best material for your upcoming CNC aluminum machining job out of all the fantastic possibilities available?
That depends on what you need specifically. For instance, 7075 is a wonderful option if your application demands high strength. MIC-6 is the best option if you’re manufacturing incredibly precise pieces. 5052 works well for electronic component parts.

Design and production come next after you’ve chosen the appropriate type of aluminum alloy for your next project.

We have skilled designers, engineers, and laborers, as well as ideal automated manufacturing lines and an efficient operating system.
Do not hesitate to start your projects with us!

Related Resources:

Anodized Aluminum: Finishing Process For Aluminum Parts
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Choose Aluminum Injection Molding for Rapid Low-Volume Manufacturing
The Pros and Cons of Aluminum Injection Molds in Plastics Manufacturing