Aluminum 7055 Alloy (UNS A97055) – Composition, Properties and Uses
Aluminium 7055 is a high-strength aluminum alloy with excellent durability and corrosion resistance. UNS A97055 has been used in various aerospace, automotive, and construction applications due to its superior mechanical properties. In this blog post, we’ll be taking a look at some of the uses and benefits of 7055 Alloy.
7055 Alloy Composition
| Element | Content (%) |
|---|---|
| Aluminum, Al | 85.9 – 88.5 |
| Zinc, Zn | 7.6 – 8.4 |
| Magnesium, Mg | 1.8 – 2.3 |
| Copper, Cu | 2 – 2.6 |
| Iron, Fe | ≤ 0.15 |
| Zirconium, Zr | 0.080 – 0.25 |
| Manganese, Mn | ≤ 0.050 |
| Chromium, Cr | ≤ 0.040 |
| Silicon, Si | ≤ 0.10 |
| Titanium, Ti | ≤ 0.060 |
| Other (each) | ≤ 0.050 |
| Other (total) | ≤ 0.15 |
7055 Alloy Physical Properties
| Properties | Metric | Imperial |
|---|---|---|
| Density | 2.86 g/cm³ | 0.103 lb/in³ |
7055 Alloy Mechanical Properties
| Mechanical Properties | Metric | English | Comments |
|---|---|---|---|
| Tensile Strength, Ultimate | 593 MPa @Thickness 25.4 mm |
86000 psi @Thickness 1.00 in |
LT Direction |
| 648 MPa @Thickness 25.4 mm |
94000 psi @Thickness 1.00 in |
Longitudinal Direction | |
| Tensile Strength, Yield | 565 MPa @Thickness 25.4 mm |
82000 psi @Thickness 1.00 in |
LT Direction |
| 614 MPa @Thickness 25.4 mm |
89000 psi @Thickness 1.00 in |
Longitudinal Direction | |
| Elongation at Break | 9.0 % @Thickness 25.4 mm |
9.0 % @Thickness 1.00 in |
LT Direction |
| 12 % @Thickness 25.4 mm |
12 % @Thickness 1.00 in |
Longitudinal Direction | |
| Compressive Yield Strength | 669 MPa @Thickness 25.4 mm |
97000 psi @Thickness 1.00 in |
Longitudinal Direction |
| Fracture Toughness | 24.2 MPa-m½ @Thickness 25.4 mm |
22.0 ksi-in½ @Thickness 1.00 in |
KIC, T-L |
| 29.7 MPa-m½ @Thickness 25.4 mm |
27.0 ksi-in½ @Thickness 1.00 in |
KIC, L-T |
7055 Alloy Uses
aluminum 7055 is widely used in the aerospace industry due to its superior strength and lightweight characteristics. It is often used in aircraft fuselage frames, skin panels, and other components such as landing gear parts, control surfaces, and engine brackets. The alloy is also frequently used in automotive applications such as light truck frames and suspension components. Additionally, it can be found in the construction industry for use in window frames and other structural components.
Corrosion Resistance
Aluminium 7055 offers exceptional corrosion resistance compared to other aluminum alloys due to its low copper content. This makes it an ideal material for use in harsh environments where corrosion needs to be minimized or prevented entirely. The alloy also has good formability characteristics, which allow it to be easily formed into complex shapes without compromising its properties.
Heat Resistance
Aluminium 7055 has good heat resistance compared to other aluminium alloys, making it suitable for higher-temperature applications such as automotive exhaust systems. Its high strength allows it to retain its properties even when subjected to elevated temperatures up to 350°C (662°F). Additionally, the alloy has good wear resistance, which increases its durability under heavy loads or repeated impacts.
Heat Treatment
Aluminium 7055 can be heat treated using conventional methods such as solution treating and ageing or precipitation hardening treatments depending on the desired mechanical properties required for a specific application. Subjecting the alloy to these processes can achieve higher strengths while maintaining good ductility and toughness. Heat treatment should always be performed by a qualified professional who is familiar with how to correctly handle aluminium alloys during these processes.
Machining & Welding
Aluminium 7055 is machinable with conventional tools but may require slightly higher speeds than other aluminium alloys due to its increased strength levels. The alloy can also be welded using gas tungsten arc welding (GTAW) or gas metal arc welding (GMAW) processes, provided that the correct filler metals are chosen for the job, and proper preheating procedures are followed during welding operations.
Conclusion:
Aluminium 7055 is an ideal material choice for many industries due to its superior strength-to-weight ratio, excellent corrosion resistance, and good machinability/weldability characteristics. When properly heat treated, this high-strength aluminium alloy can provide superior performance even under extreme conditions. Whether you’re looking for an aerospace component, an automotive part or something else entirely—aluminium 7055 should definitely be considered when selecting materials for your next project!
A passionate metal industry expert and blogger. With over 5 years of experience in the field, Palak brings a wealth of knowledge and insight to her writing. Whether discussing the latest trends in the metal industry or sharing tips, she is dedicated to helping others succeed in the metal industry.
