1. Chemical Composition of 7005 Aluminum Tube (Mass Percentage, %)

7005 aluminum alloy belongs to the Al-Zn-Mg series of weldable alloys. Its primary composition ranges are as follows (based on ASTM B221, AMS 4343, and other standards):

Aluminum (Al): Balance (approximately 91.2–94.7%)

Zinc (Zn): 4.0–5.0% (primary strengthening element)

Magnesium (Mg): 1.0–1.8% (forms strengthening phase MgZn₂ with Zn)

Manganese (Mn): 0.20–0.70% (refines grains and enhances strength)

Chromium (Cr): 0.06–0.20% (improves stress corrosion resistance)

Copper (Cu): ≤0.10% (impurity)

Iron (Fe): ≤0.40% (impurity)

Silicon (Si): ≤0.35% (impurity)

Titanium (Ti): ≤0.10% (impurity)

Other impurities: Individual ≤0.05%, total ≤0.15%

2. Mechanical Properties (Example of T53/T6 Heat Treatment States)

Mechanical properties of 7005 aluminum tube under typical heat treatment conditions (e.g., T53 or T6):

Tensile Strength (UTS):

T53 State: 350–400 MPa

T6 State: 370–420 MPa

Yield Strength (0.2% Offset):

T53 State: 290–340 MPa

T6 State: 300–360 MPa

Elongation (50mm Gauge Length):

8–12% (higher values achievable with thinner walls)

Elastic Modulus:

69–71 GPa (similar to most aluminum alloys)

Hardness:

Brinell Hardness (HB): 95–110 (T6 State)

Fatigue Strength:

~130 MPa (10⁷ cycles, T6 State)

Density:

2.78 g/cm³

3. Other Characteristics

Weldability: 7005 is one of the few high-strength weldable aluminum alloys, suitable for TIG/MIG welding. Post-weld aging is required to restore properties.

Corrosion Resistance: Superior to high-copper 7000 series alloys (e.g., 7075), but anodizing or coating is still recommended for protection.

Machinability: Moderate cold-working performance; primarily hot-extruded. Machinability is better than that of 7075.