What is difference of 6061 and 6063 Aluminum: Which Alloy Should You Select for Your Product?

In the aluminium profile industry[^1], 6061 and 6063 are the two most commonly used aluminium alloy materials. I often come across many buyers when they are choosing materials, they are often confused about which material they should use to produce their products to achieve the best results.

As an experienced person who has worked in the aluminium profile industry for more than ten years, I know very well the difference between them, and I also know what products should be made of which material will be more suitable. Today, I’m going to give you a detailed analysis of the characteristics and applicable scenarios of these two types of aluminium alloys, in the hope that you can be more accurate when choosing aluminium profiles in the future..

Aluminium profiles made of 6061 contain high levels of magnesium and silicon and have excellent mechanical properties and corrosion resistance, making them suitable for use in structural parts with high strength and machinability requirements, such as aerospace and mechanical components; while 6063 is known for its good extrusion properties and surface finish, and is commonly used in decorative structures such as architectural frames, doors and windows that do not have high strength requirements but pay attention to their appearance. [^1]

‍Difference between 6061 Aluminium and 6063 Aluminium？

Composition and mechanical properties

• 6061 Aluminium: The composition of this alloy contains more magnesium (0.8%-1.2%) and silicon (0.4%-0.8%), as well as a small amount of copper (0.15%-0.4%) and chromium (0.04%-0.35%). As a result, it has high strength and hardness, with a typical tensile strength that can reach around 290 MPa (MPa) and a yield strength of around 240 MPa. 6061 aluminium is much stronger, and is more suitable for structural products that need to withstand larger loads or strength requirements.
• 6063 Aluminium: In comparison, 6063 has a lower magnesium content (0.45%-0.9%) and silicon content (0.2%-0.6%), so it has lower mechanical strength. The tensile strength is about 210 MPa and the yield strength is about 170 MPa. However, it has very excellent extrudability and can make products with complex shapes and smooth surfaces. Therefore, 6063 is more suitable for products that do not require high strength, but require high appearance and surface quality. [^2]

The compositional differences between 6063 aluminium alloy and 6061 aluminium alloy are shown in the table below:

Note: Some values indicate maximum allowable limits (e.g., ≤0.1%).

This table provides a concise comparison of the main compositional differences between the two alloys.



### **Extrudability and Surface Finishing**

- **6061 Aluminium**: although 6061 can also be formed through the extrusion process, it will be slightly more difficult to extrude than 6063 because of its higher strength. Also, due to the higher copper content, the surface treatment effect (e.g. anodising) of 6061 is often not as good as 6063, and the surface may not be smooth enough.
- **Aluminium 6063**: This is one of the most common aluminium alloys used in the **construction industry**, and is also known as a ‘building alloy’. Its extrudability is very good, and it can be processed into a variety of complex shapes of aluminium profiles, and the surface treatment has a high degree of finish, which is very suitable for windows, door frames, curtain walls, and other construction products that require a beautiful surface.

###  **Corrosion resistance**

- **6061 Aluminium**: Due to the small amount of copper[^3] contained, 6061 is more prone to corrosion than 6063 in some specific corrosive environments (such as salt water or humid environments). However, in general use environments, 6061 still has good corrosion resistance.
- **6063 Aluminium**: Due to the very low copper content, 6063 has superior corrosion resistance, especially in the external exposure environment, the surface oxide film is more uniform and dense, so it is not easy to rust or corrosion spots in long-term use.

### **Application areas**

- **Aluminium 6061**: Due to its high strength and hardness, 6061 is usually used for **structural products**,[^4] such as **aeronautical parts**, **automotive components**, **bicycle frames**, **heavy trucks**, **ships** and **various mechanical components**. These products need to withstand large loads or impacts, so choosing 6061 can provide better structural support.
- **6063 Aluminium**: 6063, on the other hand, is widely used in the **construction sector**, such as **window frames**, **door frames**, **curtain wall profiles**, **decorative materials**, **radiators**, **railings**, and **home décor**. These products have relatively low requirements for strength, but high requirements for surface finish and aesthetics, so the extrusion performance and surface treatment advantages of 6063 are given full play.

## Flooring Solutions

While less common than other applications, UPVC is also used in flooring solutions where durability and ease of maintenance are critical. It provides a cost-effective alternative to materials like wood or stone while offering similar aesthetic qualities. This use is particularly popular in commercial settings where high foot traffic demands resilient flooring options.

 **Aluminium 6063 is more resistant to corrosion than aluminium 6061**.True
Due to the 6061 very low copper content ,the surface oxide film is more uniform and dense..

 **Aluminum 6061:This is one of the most common aluminium alloys used in the construction industry.** **False**.False
Because 6061 material is more hard, building aluminium profiles needed for the hardness requirements are not high, but the surface gloss requirements are high, so 6063 aluminium is more suitable for building aluminium..

## ‍How to choose the right aluminium?[^5]

If you are still hesitant about which aluminium alloy you should choose for your product, you can judge based on the following aspects:

- **If the product needs to withstand greater pressure or mechanical loads**, such as mechanical parts, frame structures, heavy equipment, etc., it is recommended to choose **6061 aluminium**. It is stronger and can ensure the durability and safety of the product.
- **If the product has higher requirements for appearance and surface treatment and lower mechanical properties**, such as doors and windows, decorative profiles, radiators, etc., **6063 aluminium** is recommended. It has better extrusion properties and can produce products with smooth surfaces and complex shapes.



## Summary:

**6061 and 6063** are two different types of aluminium for different purposes, each with its own advantages. **6061 is suitable for high-strength structural applications**, while **6063 is suitable for architectural and decorative profiles** where an attractive surface is required. When choosing materials, the key is to determine the material according to the use of the product, rather than just pursuing strength or surface quality. Through reasonable selection, not only can we improve the performance of the product, but also save the cost.

Through the above analysis, I believe you have a clearer understanding of the choice of 6061 and 6063 aluminium. When choosing aluminium profiles in the future, you may wish to recall these points to ensure that you choose the most suitable material to add value to your products!

[^1]: the most basic differences between 6061 and 6063 aluminium profiles

[^2]: : Learn the difference in material element content between 6061 and 6063 aluminium profiles.

[^3]: 6061 Aluminium Profiles and 6063 Aluminium Profiles Anti-Corrosion.

[^4]: Learn the application areas of 6061 and 6063 aluminium profiles respectively.

[^5]: How to choose the right aluminium