7475-T651 aluminum alloy is a 7xxx series alloy belonging to the Al-Zn-Mg-Cu system, developed for engineering applications that require very high strength. This alloy is particularly known for its high tensile strength, good fracture toughness, and fatigue resistance. The T651 temper indicates that the material has undergone solution heat treatment, stress relieving, and artificial aging processes. As a result, the alloy provides both dimensional stability and high mechanical performance. It is widely preferred for structural components used in the aerospace and defense industries.

In terms of corrosion resistance, the 7475 alloy exhibits better Stress Corrosion Cracking (SCC) resistance compared with many high-strength aluminum alloys. Especially when compared with 7075 alloy, it offers higher fracture toughness and improved SCC performance. However, it does not provide the same level of corrosion resistance as marine-grade alloys such as 5083 or 6061. Therefore, in many applications anodizing, alclad cladding, or protective surface treatments are applied to improve environmental durability.

Regarding strength properties, the 7475-T651 alloy reaches very high values. Typically, its ultimate tensile strength is around 500–540 MPa, while the yield strength is approximately 430–470 MPa. These values are higher than those of 2024-T3 alloy and in some cases approach those of 7075-T6 alloy. However, 7475 alloy can provide better fracture toughness and fatigue resistance than 7075, making it suitable for critical aircraft structures.

In terms of machinability and formability, the 7475-T651 alloy provides good machining performance, but its bending capability is limited because of its high strength structure. Bending operations are usually performed in T73 or softer tempers. Its weldability is poor, since Zn-Mg-Cu alloys of the 7xxx series tend to crack during welding. Instead, mechanical fastening, riveting, or adhesive bonding techniques are typically used.

In terms of coating capability and vibration response, 7475 alloy can be effectively protected by anodizing, alclad cladding, and various surface treatments. The material also exhibits good fatigue resistance and stable mechanical performance under vibration. Therefore, the alloy is widely used in aircraft fuselage panels, wing structures, military aircraft components, space structures, and high-performance aerospace parts. Overall, the 7475 alloy holds an important place among high-strength aerospace aluminum alloys together with 2024, 7075, and 7050 alloys.

MATERIAL COMPOSITION STANDARDS

7475 T651 is available according to the following standards:
• 7475 T651 Sheet; AMS 4090 Alloy 7475, UNS A97475, AlZn5.5MgCu
 

STOCK
Available as EN AW 7475 T651 sheet/plate and coil.

• Sheet / Plate
• Coil