Faits marquants
- 7050 and 7075 are high-strength 7xxx series alloys used in demanding aerospace and structural roles.
- 7050 offers excellent stress-corrosion resistance, good fatigue strength, and high fracture toughness — ideal for thick sections and critical parts.
- 7075-T6 and 7050 have comparable strength; 7075-T6 has slightly higher yield, while 7050-T7451 has slightly higher ultimate tensile strength.
- 7075 machines a bit better; 7050 conducts heat slightly better and is preferred for thick plates.
- Both are heat-treatable (common tempers: T6, T73, T74/T7451), and both cost more than commodity alloys.
Introduction
This guide explains the main differences between 7050 and 7075 aluminum alloys. Both are strong, lightweight 7xxx series alloys among the highest-strength aluminum alloys commercially available, with ultimate tensile strengths in the 570–590 MPa range (about 586 MPa for 7050-T7451, about 572 MPa for 7075-T6) and yield strengths around 470–505 MPa. They are workhorses for tough structural applications, especially in aerospace. Knowing their properties, strengths, and limits is essential to selecting the right one.
Comprendre les alliages d'aluminium 7050 et 7075
7050 and 7075 belong to the 7xxx series and are classed as aerospace-grade because of their high strength and good resistance to exfoliation and fatigue. Their chemistries are similar, but small differences in alloying elements create distinct performance profiles. Both are popular for lightweight structures in aircraft, sporting goods, and high-performance vehicles.
Both alloys are heat-treatable but generally not weld-friendly, with only average machinability — important when choosing between them for a given part.
Composition et propriétés de base de l'aluminium 7050
Le Alliage d'aluminium 7050 contains zinc, magnesium, manganese, titanium, silicon, copper, and zirconium. These elements give it high strength and fatigue resistance. Copper further improves properties and machinability. A key advantage of 7050 is its strong resistance to stress-corrosion cracking, which suits it to tough environments.
Zirconium refines the grain structure and helps arrest crack growth. To reach peak properties, 7050 is usually heat-treated to T7451 or T7351 — tempers known for high strength with good stress-corrosion resistance.
Composition et propriétés de base de l'aluminium 7075
Le Alliage d'aluminium 7075 also contains zinc, magnesium, and copper, with more zinc than 7050 for higher strength. Chromium aids corrosion resistance, which matters where stress corrosion is a concern.
7075 is well known for high strength at low weight. It is offered in several tempers; T6 and T651 are popular for their high strength and good machinability.
Comparaison des propriétés physiques et mécaniques
7050 and 7075 are close in composition and use, but differ subtly in mechanical properties. Those small differences decide which alloy fits a given task.
Engineers should select based on measured performance to ensure a quality, dependable final product.
Différences de résistance et de durabilité
On strength, the two are close. 7075-T6 has a slightly higher yield strength, while 7050-T7451 has a slightly higher ultimate tensile strength. Both withstand high stress before permanent deformation.
7050 has better fracture toughness, especially in thicker sections and corrosive (e.g., seawater) environments — it resists crack propagation and resists changes in shape. That makes 7050 the safer choice for critical structural parts under repeated load, where a growing crack could be catastrophic. So while 7075-T6 is usually the higher-yield option, 7050 wins on toughness and crack tolerance.
Conductivité thermique et variations du traitement thermique
7050 conducts heat a little better than 7075 (both are moderate, around 130 W/m·K), and it also has reasonable electrical conductivity. Neither is a heat-sink alloy in the way 6061 is, but 7050’s slightly higher conductivity can matter in some thermal-management roles. Both are heat-treatable to reach the required strength and hardness.
Heat treatment for both follows solution treatment, quenching, and aging, with temperatures and times tuned to the alloy and application. The T6 temper from artificial aging is common to both and raises strength.
Différences de résistance à la corrosion
Both resist corrosion, but differently. 7050 resists stress-corrosion cracking far better than 7075, making it the better pick for harsh spots such as marine or chemically exposed service.
7075 has only moderate general corrosion resistance and a higher susceptibility to stress-corrosion cracking in its peak-aged tempers. To lower that risk, 7075 is often clad with a more corrosion-resistant aluminum layer (alclad) or given protective coatings.
Températures communes Différences
Both alloys come in several tempers to ASTM and other standards. 7050 is typically T7451 or T7351; 7075 is commonly T6, T651, or T73. Each temper trades strength against toughness and corrosion resistance for the intended use.
T6 tempers in both give high strength, which is why they are favored for aerospace structures. Picking a temper means balancing strength, toughness, and corrosion resistance against service conditions.
Applications et utilisation dans l'industrie
The distinct traits of 7050 and 7075 serve different industry needs, and alloy choice usually follows project requirements.
Applications aérospatiales et aéronautiques pour 7050 et 7075
Both are widely used in aerospace. 7050’s fatigue strength and good stress-corrosion resistance make it popular for wing skins, fuselage frames, and bulkheads — parts that must survive high stress without cracking. 7075’s high strength-to-weight ratio suits landing gear and wing spars.
Différences entre les applications automobiles et structurelles
Both appear in automotive and structural builds. 7075’s high strength fits high-performance car suspension and chassis parts and bicycle frames, where low weight aids fuel economy and durability. 7050’s crack resistance suits bridges, pressure vessels, and heavy machinery parts that see sustained high stress.
7050 vs 7075 Aluminum Alloys Price Comparison
Prices for 7050 and 7075 depend on demand, raw-material cost, and processing difficulty. Both are premium alloys because of their performance versus commodity aluminum.
The price gap is often small, but 7050 can run a bit higher than 7075 due to its better stress-corrosion resistance and fatigue properties. Prices move with market conditions and order size, so confirm current quotes with suppliers.
Conclusion
7050 and 7075 are close cousins with different strengths. They share a 570–590 MPa ultimate tensile range; 7075-T6 edges yield strength while 7050-T7451 edges ultimate tensile strength and clearly leads on fracture toughness, stress-corrosion resistance, and thick-plate behavior. 7075’s trade-off is only moderate corrosion resistance and poorer weldability, managed with cladding or coatings. Choose 7050 for critical, corrosion-exposed, or thick-section structures; choose 7075-T6 where peak yield strength and machinability matter most.
Linsy Aluminum supplies both 7050 and 7075 in plate, bar, and custom forms across standard tempers, with dimension and finish customization. Typical lead times run 10–60 days depending on alloy, temper, size, and processing. Contact Linsy Aluminum to compare 7050 vs 7075 for your application and request a quote.
Questions fréquemment posées
Which is stronger, 7050 or 7075?
They are close. 7075-T6 has a slightly higher yield strength (~503 MPa) while 7050-T7451 has a slightly higher ultimate tensile strength (~586 MPa). The real difference is that 7050 also offers better fracture toughness and stress-corrosion resistance, which often matters more than raw strength for structural parts.
Which resists corrosion better?
7050 resists stress-corrosion cracking far better than 7075 and is preferred for marine or chemical exposure. 7075 has only moderate general corrosion resistance and is often clad or coated to manage it.
Which should I choose for a thick plate?
For thick plates, 7050-T7451 is usually the better choice. Its zirconium grain control and overaged temper give it superior toughness and quench-sensitive behavior in heavy sections, whereas 7075-T6 can lose toughness and SCC resistance as thickness grows.
