Surface treatment : Mill finished

Anodised

Electrophoresised

Powdercoated

Wood grain

AA ***3 is an aluminium alloy, with magnesium and silicon as the alloying elements. The standard controlling its composition is maintained by The Aluminum Association. It has generally good mechanical properties and is heat treatable and weldable. It is similar to the British aluminium alloy HE9.

***3 is mostly used in extruded shapes for architecture, particularly window frames, door frames, roofs, and sign frames. It is typically produced with very smooth surfaces fit for anodizing.

Chemical composition[

The alloy composition of ***3 is: ^[1]

• Silicon minimum 0.2%, maximum 0.6% by weight
• Iron no minimum, maximum 0.*5%
• Copper no minimum, maximum 0.*0%
• Manganese no minimum, maximum 0.*0%
• Magnesium minimum 0.*5%, maximum 0.9%
• Chromium no minimum, maximum 0.*0%
• Zinc no minimum, maximum 0.*0%
• Titanium no minimum, maximum 0.*0%
• Other elements no more than 0.*5% each, 0.*5% total
• Remainder Aluminium

The mechanical properties of ***3 depend greatly on the temper, or heat treatment, of the material

****-T5

T5 temper ***3 has an ultimate tensile strength of at least *2,**0 psi (**2 MPa) in thicknesses up to 0.*-inch (*3 mm), and *1,**0 psi (**5 MPa) from 0.5 to 1.*-inch (*5 mm) thick, and yield strength of at least *6,**0 psi (**0 MPa) up to 0.*-inch (*3 mm) and *5,**0 psi (**3 MPa) (from 0.5 to 1.*-inch (*5 mm). It has elongation of 8%.

****-T6

T6 temper ***3 has an ultimate tensile strength of at least *0,**0 psi (**6 MPa) and yield strength of at least *5,**0 psi (**5 MPa). In thicknesses of 0.***-inch (3.1 mm) or less, it has elongation of 8% or more; in thicker sections, it has elongation of *0%.

Welding

***3 is highly weldable, using tungsten inert gas welding. Typically, after welding, the properties near the weld are those of *****0, a loss of strength of up to *0%. The material can be re-heat-treated to restore a higher temper for the whole piece.