6063 aluminum alloy is an ideal material for door and window frame profiles, with magnesium and silicon as the alloying elements. It has generally good mechanical properties and is heat treatable and weldable. 6063 is the most common alloy used for aluminum extrusion. It allows complex shapes to be formed with very smooth surfaces fit for anodizing and so is popular for visible architectural applications such as window frames, door frames, roofs, and sign frames. Applications requiring higher strength typically use 6061 or 6082 instead.
6063 T5 temper has an ultimate tensile strength of at least 140 MPa (20,000 psi) in thicknesses up to 13 millimetres (0.5 in), and 130 MPa (19,000 psi) from 13 mm (0.5 in) thick, and yield strength of at least 97 MPa (14,000 psi) up to 13 millimetres (0.5 in) and 90 MPa (13,000 psi) from13 to 25 mm (0.5 to 1 in). It has elongation of 8%.