Aluminum

The answer depends on the application. For general-purpose aluminum, 3003 would be the best choice because of its corrosion resistance and workability. 6061 is a common strong structural aluminum used for the strength to weight ratio and its ability to be extruded into different shapes.

We often see aluminum as a corrosion resistant material and while that is true, aluminum corroding makes it so corrosion resistant. As aluminum corrodes, it creates an outer layer of aluminum oxide, a hard corrosion resistant coating. Unlike iron oxide (rust), this coating protects against degrading the material further. The aluminum oxide looks very similar to aluminum, which makes it harder to detect than corrosion on other materials.

Aluminum is weldable, however, there are alloys that are not recommended for welding, including the high strength aerospace alloys like 2024 and 7075. The most common alloys: 1100, 3003, 6061, and 5052 are all weldable using both MIG and TIG methods. Tig welding aluminum is recommended for beginners.

Stronger alloys used for aerospace like 2024, 6061, and 7075 can be strengthened using heat treating processes. The more general-purpose alloys, like 1100, 3003, 5052, and 5086, are only strengthened using cold working or strain hardening processes. Examples of those cold working processes include rolling, stretching and drawing through dies.

Under normal circumstances, aluminum is not magnetic because of its crystalline structure.

The best alloy for conducting heat and electricity is 1100 or other 1000 series aluminum alloys, because they are very pure and contain little to no alloying elements. Other aluminum alloys have suitable conductivity, such as 3003, which is used for heat syncing applications. 6101 is a good conductor and is preferred over 1100 because of its ability to be extruded in shapes and used for bus bar and other commercial applications.

These three tempers are solution heat treated and artificially aged, which increases the strength of the material. Depending on the shape and production method, the material may have an added process applied to it. For sheet and smaller bar stock that won’t be heavily machined, no added process is applied, so the temper is simply T6.

T651 temper has an added stress relieving process and is used for rolled bar and plate which prevents warping while machining. For extruded rod and bar shapes, the T6511 temper is applied. This temper is also stress relieved, but an applied straightening process ensures the bar is as straight as possible after extruding.

The answer is yes if done correctly. The T6 temper is known to not bend easily without cracking, it is best to temper the material after forming. If that is not possible, there are a few steps to take that will help you bend that material.

• Heat the material
• Keep your bend radius large compared to the thickness of your material
• Bend perpendicular to the grain of the material not parallel to the grain