6061 t6 aluminium vs 7075 aluminium

6061 t6 aluminium vs 7075

Aluminum alloys 6061-T6 and 7075 are widely used in engineering applications, but they have different properties and are suited to different purposes. Below is a detailed comparison of these two alloys in terms of their mechanical properties, physical properties, and typical uses:

Comparison Between 6061-T6 and 7075 Aluminium

Property6061-T6 Aluminum7075 Aluminium
Composition0.8-1.2% Mg, 0.4-0.8% Och, 0.15-0.4% Cu, 0.04-0.35% Cr5.1-6.1% Zn, 2.1-2.9% Mg, 1.2-2.0% Cu, 0.18-0.28% Cr
Tensile Strength310 MPa (45 ksi)572 MPa (83 ksi)
Yield Strength275 MPa (40 ksi)503 MPa (73 ksi)
Elongation at Break12%11%
Hardness (Brinell)95 HB150 HB
Modulus of Elasticity68.9 GPa (10,000 ksi)71.7 GPa (10,400 ksi)
Densitet2.70 g/cm³2.81 g/cm³
Fatigue Strength96 MPa (14 ksi)159 MPa (23 ksi)
Thermal Conductivity167 W/m·K130 W/m·K
KorrosionsbeständighetExcellentFair to Poor (without protective coating)
WeldabilityExcellentPoor
BearbetningsbarhetGoodFair to Good
Heat TreatmentHeat treatable to T6 conditionHeat treatable to T6 or T73 condition

Key Differences in Properties

  1. Strength:
    • 7075 Aluminium is much stronger, with a tensile strength of 572 MPa compared to 310 MPa for 6061-T6. This makes 7075 aluminum ideal for high-stress structural applications.
  2. Korrosionsbeständighet:
    • 6061-T6 Aluminum har utmärkt korrosionsbeständighet, especially against atmospheric and marine conditions, while 7075 Aluminium has fair to poor corrosion resistance and often requires a protective coating or anodizing for use in corrosive environments.
  3. Weldability:
    • 6061-T6 Aluminum is highly weldable, making it suitable for structures requiring frequent welding. 7075 Aluminium is difficult to weld and can suffer from cracking and brittleness after welding.
  4. Bearbetningsbarhet:
    • 6061-T6 Aluminum is known for its good machinability, which is better than that of 7075 Aluminium, although 7075 still offers acceptable machinability for most applications.
  5. Densitet:
    • 7075 Aluminium is slightly denser (2.81 g/cm³) than 6061-T6 Aluminum (2.70 g/cm³), which can affect weight-sensitive applications.
  6. Thermal Conductivity:
    • 6061-T6 Aluminum has better thermal conductivity (167 W/m·K) compared to 7075 Aluminium (130 W/m·K), making it preferable for heat-exchange applications.

Comparison of Uses

Application Area6061-T6 Aluminum7075 Aluminium
AerospaceAircraft fittings, fuel tanks, and fuselage structuresHigh-stress structural parts like aircraft wings, fuselage frames, and landing gear
AutomotiveChassis, wheel spacers, and engine componentsRacing components like suspension parts, gears, and shafts
MarineBoat hulls, masts, and marine fittingsNot typically used due to poor corrosion resistance
General ConstructionStructural components, piping, and framesNot common; only when high strength is needed
Sports EquipmentBicycle frames, camping equipment, and scuba tanksHigh-performance bicycle components, climbing equipment
ElectronicsHeat sinks and electrical fittingsNot typically used; 6061 is preferred for thermal applications
Consumer GoodsLadders, furniture, and household itemsPremium products where high strength is desired, such as rugged outdoor gear

Summary

  • 6061-T6 Aluminum is more versatile, easier to work with, and has excellent corrosion resistance, making it suitable for a wide range of applications, including marine, bil-, construction, and electronics.
  • 7075 Aluminium offers superior strength, making it ideal for high-stress applications like aerospace and high-performance sports equipment, but it has poorer weldability and corrosion resistance, limiting its use in certain environments.