Chemical Composition: Aluminium Al: margin silicon Si: 0.40 ~ 0.8 Copper Cu: 0.15 ~ 0.40 Mg Mg: 0.8 ~ 1.2 Zinc Zn: ≤ 0.25 Manganese Mn: ≤ 0.03 Titanium Ti: ≤ 0.15 Chromium Cr: 0.04 ~ 0.35 Iron Fe: 0.000 0.700 Note: Single: ≤ 0.05; Total: ≤ 0.15 
 Mechanical properties: tensile strength σb (MPa) 170 ~ 240 conditions, the yield strength σ0.2 (MPa) ≥ 70 sample size: all thickness Note: Vertical room temperature mechanical properties of pipe