Choosing aerospace and defence materials is a unique challenge. It goes beyond the usual cost and supply issues—given the critical nature of material performance in combat situations. Material inefficiency, or even failure, in-the-field is unacceptable. Thus, it’s important to know the minute differences between distinct, yet closely related, material grades.

Take aluminum alloys. They play a key role in defence applications because of their light weight and high strength. But there are many similar variations. 5754 aluminum alloy, for instance, is a common choice, but even that comprises two temper variations: H12 and H22. So, how do 5754-H12 and H754-H22 differ?

Mechanical Properties

5754-H22

5754-H22 is a temper that has been work-hardened and then partially annealed to achieve a quarter-hard state. This tempering process results in a tensile strength range of 245 to 290 MPa, making it suitable for applications requiring a balance of strength and ductility. The alloy also exhibits an elongation of 10 to 15%, which indicates its capacity to stretch under tension before breaking. Additionally, the Brinell hardness of 5754-H22 is approximately 63 HB, highlighting its resistance to indentation and wear, which is crucial for structural applications​.

5754-H12

While specific data for 5754-H12 is less commonly available, the general understanding of the H12 temper suggests it is work-hardened to a lesser degree than H22. This means that 5754-H12 would typically have lower tensile strength and hardness compared to its H22 counterpart. However, this does not diminish its value. The reduced work-hardening makes it better for applications where moderate strength is adequate, and greater malleability is required. The balance between hardness and workability makes 5754-H12 an ideal choice for forming operations where more complex shapes are necessary​.

Applications

5754-H22

Due to its higher strength and excellent corrosion resistance, 5754-H22 is widely used in demanding applications. These include shipbuilding, vehicle bodies, and welded structures where durability and reliability are paramount. The alloy’s resilience also makes it an excellent choice for flooring applications, particularly in environments where the material will be subjected to heavy wear and tear. The H22 temper’s ability to maintain its integrity under stress is a key factor in its widespread use in these fields​.

5754-H12

5754-H12, with its combination of moderate strength and increased ductility, finds its niche in applications where the material needs to be easily shaped or formed. This makes 5754-H12 ideal for use in automotive components, where complex geometries are often required. Additionally, 5754-H12’s good corrosion resistance, similar to that of H22, ensures longevity in challenging environments, albeit in less structurally demanding roles. H12 temper’s flexibility makes it particularly useful in manufacturing processes that require significant forming, bending, or drawing​.

General Characteristics

Both 5754-H12 and 5754-H22 share a common base alloy, characterized by high magnesium content. This composition is what grants them their notable corrosion resistance, particularly in marine environments. Moreover, the 5754 alloy, regardless of temper, is known for its excellent weldability. Its weldability is a critical feature for constructing large structures or components that require reliable joints. The alloy’s ability to maintain good workability, even in cold conditions, further broadens its range of applications​​.

Which Is The Right Material For You, 5754-H12 or 5754-H22?

When comparing 5754-H12 and 5754-H22, it’s clear both offer significant advantages depending on the specific requirements of the application. 5754-H22, with its higher strength and hardness, is the go-to option for structural applications demanding durability and resistance to wear. On the other hand, 5754-H12 provides a more balanced approach. 5754-H12 offers sufficient strength with enhanced formability, making it suitable for parts requiring intricate shaping. Both tempers uphold the superior corrosion resistance that the 5754 alloy is known for, ensuring long-lasting performance in even the most challenging environments.

For more information about these alloys and their availability, you can visit Masteel. We are a leading provider of high-grade aluminum products tailored to meet the demands of the defense industry. Contact us today to uncover more insights about the materials we can offer.