Aluminium 7075

The Aluminium 7075, an aluminium alloy with zinc as the main alloying element, stands as one of the most significant and employed materials in the aerospace and defence industry. Its reputation is founded upon its extraordinary strength and fatigue resistance, qualities that make it a preferred option for the most demanding and critical applications in these highly specialised and critical sectors.

Pros

Excellent strength-to-weight ratio: Compared to other common aluminium alloys such as 6061-T6 and 5083-H112, Aluminium 7075 offers superior strength. With a minimum tensile strength of at least 572 MPa, yield strength of at least 503 MPa, and elongation of at least 9%, this material provides superior mechanical performance. Its lightweight nature makes it ideal for applications where weight reduction is crucial, such as in the aerospace and automotive industries.

Outstanding fatigue resistance: Aluminium 7075 exhibits excellent fatigue resistance, allowing the material to withstand repeated loads without failure. This characteristic makes it ideal for applications subjected to cyclic stresses, ensuring durability and reliability over time.

Good machinability: The machinability of this alloy enables easy welding, machining, and forming, offering flexibility in the production process. This allows for greater versatility in the use of 7075 in a wide range of industrial applications.

Cons

Susceptible to natural corrosion: Aluminium 7075 (Ergal) is vulnerable to natural corrosion, which can be a limitation in applications exposed to corrosive environments such as marine or industrial settings. This necessitates additional precautions and, at times, special treatments to protect components from wear caused by corrosion.

Higher cost compared to other alloys: Compared to other aluminium alloys, 7075 tends to have a higher cost. This may make it an expensive choice in some production contexts, especially when more economical alternatives with satisfactory performance are available. It is therefore important to carefully assess the cost-benefit ratio when deciding to use this alloy.

Difficult to weld: Another point to consider is the difficulty in welding this alloy. This process requires specialised skills and equipment to achieve high-quality joints. The complexity of welding can influence the design and manufacture of components, necessitating additional planning and preparation during the production process.

Applications of aluminium 7075

This aluminium is widely employed across a variety of industrial sectors owing to its exceptional mechanical and physical properties.

In the aerospace and defence industry, Aluminium 7075 is the preferred choice for demanding and critical applications that require high mechanical performance and fatigue resistance. It is used in the production of structural components such as aircraft parts and defence systems, where robustness and reliability are paramount.

In the automotive industry, Ergal 7075 finds application in high-performance components like suspension arms and brake calipers. Its lightweight nature, combined with superior corrosion resistance, makes it ideal for applications requiring lightweight yet sturdy components, thereby enhancing the performance and efficiency of vehicles.

Similarly, in the marine industry, this alloy is utilised for components subjected to aggressive marine conditions, such as propeller shafts and hull plates. Its corrosion resistance makes it a reliable choice for marine applications, where protection against wear caused by saltwater is essential for component durability.

In the sporting goods sectors, it is used in the manufacture of bicycle frames, golf club heads, skis, and other sports equipment. Its combination of strength and lightweight properties makes it ideal for applications requiring durable and high-performing components, enabling athletes to achieve optimal performance during use.

Aluminium 7075 continues to be a reliable and versatile choice across a wide range of industrial sectors, where its exceptional properties contribute to enhancing the performance and durability of components in various applications.

Conclusion

The 7075 alloy is one of the most significant and widely used materials in the aerospace and defence industry, owing to its exceptional strength and fatigue resistance. These qualities make it a preferred choice for demanding and critical applications in highly specialised and critical sectors.

Among its strengths, the 7075 alloy offers an excellent strength-to-weight ratio, surpassing other common aluminium alloys and providing superior mechanical performance. Its lightweight nature makes it ideal for applications where weight reduction is crucial, such as in the aerospace and automotive industries. Furthermore, its excellent fatigue resistance allows the material to withstand repeated loads without compromise, ensuring durability over time.

However, some limitations need to be considered, such as vulnerability to natural corrosion, which requires additional precautions in applications exposed to corrosive environments, and the relatively higher cost compared to other aluminium alloys. Welding difficulty is another point of concern, as this process requires specialised skills and equipment to achieve high-quality joints, influencing the design and manufacturing of components.

Despite these limitations, Aluminium 7075 finds extensive use in various industrial sectors due to its exceptional mechanical and physical properties. In the aerospace and defence, automotive, marine, and sporting goods industries, this material is used for a wide range of applications requiring strength, reliability, and superior performance. Ultimately, the 7075 alloy remains a reliable and versatile choice, contributing to the enhancement of performance and durability of components across multiple industrial contexts.