7150 T651 Aluminum
7150-T651 is an ultra-high strength aerospace aluminum alloy with limited corrosion resistance. It relies on heat treatment for strengthening and is suitable for high-load applications where corrosion protection is necessary. The machined surface is sensitive to corrosion and requires protective treatment during use.
7150 aluminum alloy is a high-strength, heat-treatable forged alloy in the 7000 series, primarily used in demanding aerospace applications. It is essentially a refined version of alloy 7050, offering enhanced mechanical properties while maintaining compatibility.
Why Choose 7150-T651?
- Excellent strength-to-weight ratio
- Superior fatigue and fracture toughness
- Compatible with common high-strength aluminum alloys
- Trusted in high-performance aerospace structures
7150-T651 is a high-performance aerospace alloy that remains strong, tough, and reliable under extreme conditions, making it an ideal choice for critical structural components.
7150 T651 Aluminum Production and Certification Standards
Specifications:
- AMS 4306: Governs aerospace plates.
- ASTM B209: Standard for dimensional tolerances and testing.
- Certifications: AS9100 (aerospace), NADCAP (heat treatment/NDT), and ISO 9001.
- Form Availability: Plates (4–260 mm thick), bars, tubes, and custom extrusions.
| Product Form | Description |
| 7150 T651 Aluminum Plates | 7150 T651 aluminum alloy plates are typically available in thicknesses ranging from 4 to 260 mm, offering extremely high strength and excellent fatigue performance. They are ideal for aerospace structural components such as wing skins, fuselage joint plates, and other high-load-bearing parts. In the T651 temper, the plates undergo heat treatment and artificial aging, resulting in good dimensional stability and machinability, making them suitable for large-scale precision cutting and machining operations. |
| 7150 T651 Aluminum Bars | 7150 T651 aluminum alloy bars are widely used in aerospace for precision-machined components such as connectors, brackets, and load-transmitting parts due to their excellent tensile strength and toughness. These bars are well-suited for high-precision turning, milling, and drilling operations, especially in applications that demand high structural performance. |
| 7150 T651 Aluminum Tubes | 7150 T651 aluminum alloy tubes combine lightweight and high strength with good corrosion resistance, making them commonly used in aerospace hydraulic systems, structural frameworks, and weight-reducing structural connectors. Their inner and outer diameter tolerances are tightly controlled, offering a favorable strength-to-weight ratio and high compressive/internal pressure resistance. |
| 7150 T651 Aluminum Custom Extrusions | 7150 T651 aluminum alloy custom extrusions can be precisely die-designed and extruded according to specific engineering structures, meeting the demands of complex load paths or nested structural configurations. They are suitable for airframe reinforcement members, rail components, seat frames, and large aerospace assembly structures, offering excellent ductility and integrated design advantages while maintaining high strength. |
7150 T651 Aluminum Chemical Composition
| Element | Range (%) |
| Zn | 6.4–6.6 |
| Mg | 2.0–2.9 |
| Cu | 1.2–2.2 |
| Fe | ≤ 0.20 |
| Cr | 0.10–0.22 |
| Si | ≤ 0.15 |
| Ti | ≤ 0.10 |
| Mn and others | Minor amounts (≤ 0.20) |
7150 Aluminum Mechanical Properties (Tempered T651)
| Property | Typical Value | Description |
| Tensile Strength | ≥572 MPa | Higher than common aluminum alloys (e.g., 6061) |
| Yield Strength | ≥503 MPa | A key metric for high load-bearing capacity |
| Hardness and Wear Resistance | Extremely high | Suitable for high-stress components |
| Corrosion Resistance | Poor (requires surface protection) | The near-surface deformed layer is prone to preferential corrosion |
7150 Aluminum Heat Treatment (T651 Temper)
T651 typically includes:
- Solution heat treatment
- Quenching
- Stress-relief stretching
- Artificial aging
This process achieves excellent strength and toughness. Variants such as T7751 and T6151 focus on optimizing corrosion resistance and other performance characteristics.
Heat Treatment Process:
- Solution treatment: heated to approximately 480°C to dissolve alloying elements.
- Stress relief: stretched to 0.5–3% permanent deformation to minimize residual stress.
- Artificial aging: aged at 120–130°C to reach peak strength.
7150 T651 Aluminum Aerospace Applications
7150-T651 is preferred for critical aircraft components that require a high strength-to-weight ratio:
Major structures: fuselage frames, wing spars, and landing gear supports.
Typical Applications
- Aerospace structural components (such as aircraft frames and landing gears)
- High-stress molds, mechanical bearings, and wear-resistant parts
7150 T651 Aluminum Advantages
- 10–15% higher strength than 7075-T651, with improved fracture toughness.
- Low residual stress after stretching, suitable for machined bulkheads and ribs.
7150 T651 Aluminum Performance Highlights and Applications
- High fatigue resistance and excellent strength make it a preferred choice for wing spars, fuselage bulkheads, landing gears, and missile structures.
- Good resistance to stress corrosion, though still needs monitoring; careful tempering and final heat treatment are crucial to minimizing risk.
- Also used for producing aerospace structural components such as extrusions, plates, profiles, and forged inlet ducts for fuel tank bulkheads and wing spars.
7150 T651 Aluminum vs. 7000 Series Products
- Higher strength than 7075-T651, with slightly better corrosion resistance.
- Comparable strength to top-tier alloys such as 7449-T7951, though 7449 may offer superior corrosion resistance.
| Alloy/Temper | Tensile Strength (MPa) | Corrosion Resistance | Primary Applications |
| 7150-T651 | 500–530 | Moderate | Wing spars, fuselage frames |
| 7075-T651 | 475 | Low | Aircraft skins, military hardware |
| 7050-T7451 | 441 | Good | Thick-section military aircraft parts |
| 7449-T7951 | >570 | Excellent | Upper wing skins (corrosion-critical) |
7150 T651 performs excellently in terms of strength and machinability but lags behind 7449 in corrosion resistance and 7050 in thick-section property uniformity.
7150 T651 Aluminum Machining and Manufacturing Considerations
- Machinability: Good, but requires sharp tooling and low vibration to prevent cracking; chip-breaking design helps reduce heat buildup.
- Welding: Welding is challenging due to the risk of hot cracking. Friction Stir Welding (FSW) is recommended for critical joints.
- Forming: Limited to minor bending (≤90°) without cracking; post-forming aging treatment may be required.
7150-T651 is an ideal choice for high-stress aerospace structures (such as wing spars and landing gears), where strength and weight reduction are more critical than corrosion resistance. For corrosive environments (such as marine or unpainted interiors), T77 temper or alloys like 7449 offer better alternatives than 61215. Its balance of machinability, fracture toughness, and certification compliance ensures continued use in next-generation aircraft, although surface protection remains essential.
