What is the difference between 6061 and 6063 aluminum pipe?

In the world of aluminum products, 6061 and 6063 aluminum pipes are two commonly used types. Zhonglian Aluminum, a professional aluminum profile manufacturer and supplier with over 32 years of extrusion experience, is well - versed in the characteristics of these two alloys. We offer a one - stop aluminum production and processing service, including aluminum profile mold opening, extrusion, surface treatment, and CNC deep processing, which allows us to better understand the nuances between different aluminum materials.​

6061 Aluminum Pipe​

6061 aluminum contains alloying elements such as magnesium (Mg) and silicon (Si). The magnesium content typically ranges from 0.8 - 1.2%, and the silicon content is around 0.4 - 0.8%. It also has a small amount of copper (Cu) ranging from 0.15 - 0.4%, and chromium (Cr) in the range of 0.04 - 0.35%. The presence of these elements, especially copper, contributes to its relatively higher strength compared to some other aluminum alloys in the 6xxx series.​

6063 Aluminum Pipe​

6063 aluminum also has magnesium and silicon as its main alloying elements. However, the magnesium content is usually 0.45 - 0.9%, and the silicon content is 0.2 - 0.6%, which are generally lower than those in 6061. Additionally, 6063 aluminum has a negligible amount of copper (usually less than 0.1%). The difference in chemical composition is the root cause of the variance in their properties.​

1. Tensile Strength​

✅ 6061 Aluminum Pipe: In the T6 temper (a common heat - treated condition), 6061 aluminum pipes can achieve a tensile strength of approximately 290 MPa. This high tensile strength makes it suitable for applications where the pipe needs to withstand significant pulling or stretching forces, such as in some structural and mechanical applications.​

✅ 6063 Aluminum Pipe: For 6063 aluminum pipes in the T6 temper, the tensile strength is around 186 MPa. While it is still a strong alloy, it has a lower tensile strength compared to 6061, which may limit its use in high - stress applications.​

2. Yield Strength​

✅ 6061 Aluminum Pipe: The yield strength of 6061 aluminum in the T6 temper is about 276 MPa. This indicates that it can resist a large amount of stress before permanent deformation occurs.​

✅ 6063 Aluminum Pipe: In contrast, the yield strength of 6063 aluminum in the T6 temper is approximately 214 MPa. This means that 6063 aluminum pipes will start to deform under a lower level of stress compared to 6061 pipes.​

3. Hardness​

✅ 6061 Aluminum Pipe: In terms of hardness, 6061 aluminum in the T6 temper has a Brinell hardness of around 95. Its relatively high hardness makes it more resistant to wear and indentation.​

✅ 6063 Aluminum Pipe: 6063 aluminum in the T6 temper has a Brinell hardness of about 73, which is lower than that of 6061. As a result, 6063 pipes may be more prone to surface damage in abrasive environments.​

1. Thermal Conductivity​

6061 Aluminum Pipe: The thermal conductivity of 6061 aluminum ranges from 151 - 202 W/(m·K). This property makes it useful in applications where heat transfer needs to be managed, such as in some heat - exchanger related components.​

6063 Aluminum Pipe: 6063 aluminum has a slightly higher thermal conductivity, typically in the range of 201 - 218 W/(m·K). This means that 6063 pipes can transfer heat more efficiently than 6061 pipes in some cases.​

2. Density​

Both 6061 and 6063 aluminum pipes have a density of approximately 2.7 g/cm³. This relatively low density is a common advantage of aluminum alloys, making them lightweight materials, which is beneficial for applications where weight reduction is crucial, such as in the transportation industry.​

3. Corrosion Resistance​

✅ 6061 Aluminum Pipe​

6061 aluminum has good corrosion resistance. However, due to the presence of copper in its composition, it is more susceptible to corrosion in certain aggressive environments, especially those with high salt content. In such conditions, surface treatments like anodizing or painting are often required to enhance its corrosion resistance.​

✅ 6063 Aluminum Pipe​

6063 aluminum generally exhibits excellent corrosion resistance. Since it contains little to no copper, it is more resistant to corrosion compared to 6061 in many environments. This makes it a popular choice for outdoor applications where long - term exposure to the elements is expected, such as in architectural projects.​

1. Machinability​

6061 Aluminum Pipe: 6061 aluminum is considered to have good machinability. However, due to its relatively high strength, it may require more power and specific machining techniques compared to some softer aluminum alloys. Tools with appropriate hardness and sharpness are needed to ensure efficient machining and a good surface finish.​

6063 Aluminum Pipe: 6063 aluminum has fair to good machinability. It is easier to machine compared to 6061 in some aspects because of its lower strength. This makes it a preferred choice when complex shapes need to be machined with less effort and cost.​

2. Weldability​

6061 Aluminum Pipe: 6061 aluminum has decent weldability. It can be welded using various methods such as TIG (Tungsten Inert Gas) welding and MIG (Metal Inert Gas) welding. However, proper pre - and post - welding treatments are often necessary to ensure the integrity of the welded joint, especially when dealing with high - strength applications.​

6063 Aluminum Pipe: 6063 aluminum also has good weldability. In fact, it is often considered more weld - friendly than 6061 in some cases. The welding process for 6063 aluminum can result in joints with good mechanical properties and a relatively smooth appearance.​

1. 6061 Aluminum Pipe Applications​

✅ Aerospace Industry: 6061 aluminum pipes are used in aircraft structures and fittings. Their high strength - to - weight ratio is crucial for reducing the overall weight of the aircraft while maintaining structural integrity, which is essential for fuel efficiency and performance.​

✅ Automotive Industry: They are used in truck and bus bodies, wheels, and various automotive components such as brake and hydraulic pistons. The high strength of 6061 aluminum can withstand the mechanical stresses and vibrations experienced in automotive applications.​

✅ Marine Applications: 6061 aluminum pipes are suitable for shipbuilding, including sailboats, yachts, and marine fittings. Despite its slightly lower corrosion resistance compared to 6063 in some environments, proper surface treatments can make it durable for marine use.​

2. 6063 Aluminum Pipe Applications​

Architectural Field: 6063 aluminum pipes are extremely popular in architecture. They are used for window frames, door frames, stair rails, and structural supports. Their excellent corrosion resistance, good surface finish, and relatively easy extrusion into complex shapes make them ideal for enhancing the aesthetics and durability of buildings.​

Home Goods and General Construction: In the production of aluminum furniture and recreational equipment, as well as in general construction for items like pipes, tubing, and signage, 6063 aluminum pipes are commonly used. Their combination of properties, including corrosion resistance and workability, makes them well - suited for these applications.​

In conclusion, while both 6061 and 6063 aluminum pipes have their own unique characteristics, understanding their differences in chemical composition, mechanical and physical properties, corrosion resistance, machining, and applications is crucial for making the right choice in various projects. At Zhonglian Aluminum, our expertise allows us to provide high - quality 6061 and 6063 aluminum pipes and offer professional advice to help our customers select the most suitable product for their specific needs.