7005 aluminium alloy

7005 is an aluminium alloy used primarily for less expensive bicycle frames, due to its relative ease of welding and manufacture, it not requiring expensive heat treating. It has similar physical properties to 6061 aluminium alloy, except it has a higher density of 2.78 g/cm³ (as opposed to 2.70 g/cm³ or ≈ +3%), and depending on the temper, may be slightly stronger.

It does not need to be precipitation hardened, unlike 6061, but can be cooled in air.

Specific forms of AL 7005 include:

• 7005-O
• 7005-T5
• 7005-T53
• 7005-T6

Chemical composition

The alloy composition of 7005 is:

• Aluminium 91.0% - 94.7%
• Chromium 0.06% - 0.20%
• Copper <=0.10 %
• Iron <=0.40 %
• Magnesium 1.0% - 1.80%
• Manganese 0.20% - 0.70%
• Silicon <=0.35%
• Titanium 0.010% - 0.060%
• Zinc 4.0% - 5.0%
• Zirconium 0.080% - 0.20%
• Other, total <= 0.15%