Aluminium exhibition | Extensive Use of Ultra-High-Strength Aluminum Alloys in Aerospace

Aluminum alloy, as a mature lightweight high-strength alloy material, is extensively used in aerospace. These alloys generally serve as structural materials, boasting greater specific strength and superior machinability compared to steel.

The aerospace sector primarily focuses on the development of aluminum alloys with high strength, toughness, and corrosion resistance to meet the stringent demands of aerospace applications. The 2000 and 7000 series aluminum alloys are commonly used. Advances are made by refining the manufacturing processes and tweaking the material composition of these high-strength alloy materials. Innovative production methods, such as powder metallurgy and spray forming, have been employed to create aluminum alloys with even better properties. Research is also underway on Aluminum matrix composites and Superplastic aluminum alloy material.

Throughout the development and application of lightweight, high-strength aluminum alloys, stress corrosion has been a persistent issue. Addressing, mitigating, or delaying the stress corrosion of these alloys during use remains a significant challenge.

The Aluminum Exhibition found that the 2000 series aluminum alloys, which are widely used in aerospace, primarily consist of aluminum (Al), copper (Cu), and magnesium (Mg). The 7000 series mainly includes Al, zinc (Zn), Mg, and Cu. Additionally, some high-performance aluminum alloys (offering high strength, toughness, and corrosion resistance) have been developed by introducing specific elements. Currently, modifying the casting conditions is the primary method to achieve these high-performance aluminum materials.

The 2000 series aluminum alloys mainly contain Cu as the primary alloying element. Adding an appropriate amount of Cu to aluminum can enhance its strength, heat resistance, and machinability. However, corrosion resistance may decline, as Cu tends to facilitate intergranular corrosion in the alloy. Hence, the constituents of the material directly influence the alloy's properties. As a protective measure, the surface of the 2000 series alloys is usually clad with pure aluminum or the 6000 series aluminum alloy, acting as an electrochemical protective film to boost corrosion resistance. Subsequent studies have investigated various methods to enhance the stress corrosion resistance of different alloy grades, to some extent, mitigating the rate of aluminum alloy stress corrosion.

Aluminum alloy materials play a crucial role in ensuring the safe flight of aircraft. The selection and performance prediction of aluminum materials for different parts directly impact the aircraft's reliability and safety. Predicting the failure issues of aerospace aluminum materials is of paramount importance as it directly pertains to human safety and demands widespread attention.

High-performance, high-strength aluminum alloys are primarily used in aerospace and military sectors. Given the intense demands for weight reduction in aerospace and military products, materials with high specific strength are preferred. In aircraft materials, the 7000 series high-strength and tough aluminum alloys, along with the 2000 series medium-strength and tough alloys, play a pivotal role.

As noted by the Aluminum Exhibition, with the continuous advancement in forming technology and processing techniques for high-strength, lightweight aluminum alloy materials, the intrinsic material properties are continually improved. Their processing and forming technologies are also continuously enhanced, highlighting the quintessential advantages of lightweight metals in high-end manufacturing.