I. Chemical Composition of Common Aluminum Alloy Tubes

The chemical compositions of different aluminum alloy grades vary significantly. Below are the typical composition ranges (wt%) for several common alloys:

1. 6061 (Al-Mg-Si Series)

Aluminum (Al): Balance

Magnesium (Mg): 0.8–1.2

Silicon (Si): 0.4–0.8

Copper (Cu): 0.15–0.4

Chromium (Cr): 0.04–0.35

Iron (Fe): ≤0.7

Manganese (Mn): ≤0.15

Zinc (Zn): ≤0.25

Others: ≤0.15

2. 6063 (Al-Mg-Si Series, Commonly Used for Architectural Profiles)

Aluminum (Al): Balance

Magnesium (Mg): 0.45–0.9

Silicon (Si): 0.2–0.6

Iron (Fe): ≤0.35

Copper (Cu): ≤0.1

Manganese (Mn): ≤0.1

Chromium (Cr): ≤0.1

3. 7075 (Al-Zn-Mg-Cu Series, High-Strength Alloy)

Aluminum (Al): Balance

Zinc (Zn): 5.1–6.1

Magnesium (Mg): 2.1–2.9

Copper (Cu): 1.2–2.0

Chromium (Cr): 0.18–0.28

Iron (Fe): ≤0.5

Silicon (Si): ≤0.4

4. 3003 (Al-Mn Series, Excellent Corrosion Resistance)

Aluminum (Al): Balance

Manganese (Mn): 1.0–1.5

Copper (Cu): ≤0.2

Iron (Fe): ≤0.7

Silicon (Si): ≤0.6

II. Mechanical Properties

The mechanical properties of aluminum alloy tubes depend on alloy grade, heat treatment state (e.g., T6, T4, O), and processing techniques. Typical properties under standard conditions are listed below:

1. 6061-T6 (Solution Heat Treated + Artificial Aging)

Tensile Strength (UTS): ≥310 MPa

Yield Strength (YS): ≥276 MPa

Elongation: ≥12%

Hardness: ~95 HB

2. 6063-T5 (Artificial Aging)

Tensile Strength: ≥190 MPa

Yield Strength: ≥160 MPa

Elongation: ≥8%

Hardness: ~60 HB

3. 7075-T6 (High Strength)

Tensile Strength: ≥570 MPa

Yield Strength: ≥505 MPa

Elongation: ≥11%

Hardness: ~150 HB

4. 3003-H14 (Half-Hard Temper)

Tensile Strength: ≥145 MPa

Yield Strength: ≥125 MPa

Elongation: ≥8%

Hardness: ~40 HB