7040 T7451 is one of the high-strength aluminum alloys in the 7000 series (zinc-magnesium-copper based). Its chemical composition typically contains 5.7–6.7% zinc (Zn), 1.9–2.4% magnesium (Mg), and 1.5–2.3% copper (Cu). Additionally, it contains small amounts of silicon, iron, and chromium as trace elements. This special composition provides the alloy with high strength while keeping its weight low, making it an ideal material for high-performance applications such as aerospace. The T7451 temper is achieved through solution heat treatment, aging, and stabilization processes, optimizing the alloy's strength and durability.

In terms of mechanical properties, 7040 T7451 is very strong. Its tensile strength can reach up to 450 MPa, and its yield strength is approximately 400 MPa. At the same time, with an elongation of around 7%, it ensures sufficient ductility and fracture resistance. This combination makes 7040 T7451 suitable for high-load structural components, aircraft fuselage spars, defense industry parts, and other critical engineering applications. The durability provided along with its high strength ensures safe use under heavy loads.

Regarding machinability, 7040 T7451, despite being a high-strength alloy, shows satisfactory performance in machining operations. CNC milling, drilling, and cutting can be applied; however, due to its hardness, it is important to work with appropriate cutting tools and correct process parameters. Weldability is limited; especially in MIG or TIG welding, care must be taken, and pre-heat treatment may be necessary. Therefore, for critical structural applications, mechanical fastening methods are preferred over welding.

In terms of corrosion resistance, 7040 T7451 performs well among 7000 series alloys. The naturally formed oxide layer on the alloy's surface provides protection against atmospheric conditions and mild seawater. In more aggressive environments or in high-chloride conditions such as open seawater, additional protection through anodizing or suitable coating methods can be applied. These properties make 7040 T7451 suitable for aerospace, defense industry, automotive, and high-performance engineering applications.

MATERIAL COMPOSITION STANDARDS

Characteristic Properties of 7040 T7451: 

• Strength: Excellent
• Machinability: Above Average
• Weldability: Poor
• Formability: Reasonable
• Corrosion Resistance: High
• Heat Treatable: Yes
   

Some Well-Known Applications of 7040 T7451: 
Primarily in the aerospace industry,
Aircraft fuselage components,
Cockpit window structures.
 

STOCK
7040 T7451 is available in sheet/plate form.

• Sheet/Plate