6061 Aluminum I-Beam, Unpolished (Mill) Finish, Extruded, T6-Temper, ASTM B221, Equal Leg Length, Squared Corners, 3" Leg Lengths, 4" Width, 0.29" Wall Thickness, 12" Length, OnlineMetals

The 6061 aluminum I-beam with equal leg length and squared corners has an unpolished (mill) surface, meets American Society for Testing and Materials International ASTM B221 specifications, and has a standard tolerance. The 6061 aluminum alloy is a general-purpose material that combines good corrosion resistance, strength, machinability, and weldability. It resists stress corrosion cracking and is heat treatable. The material has been extruded, a process of compressing metal and pushing it through a die to create the shape.

Aluminum and aluminum alloys are lightweight compared to steel, brass, and copper, and have high strength-to-weight ratios. They offer good corrosion resistance and conductivity of heat and electricity, as well as moderate formability and machinability. Aluminum alloys include elements that modify the aluminum to achieve specific properties such as better weldability or greater strength. All series of aluminum alloys are nonmagnetic. Aluminum alloys have temper designations, indicating that the material has undergone a process to achieve certain properties of strength and hardness.

Tensile strength, used to indicate the material’s overall strength, is the peak stress it can withstand before it breaks. Corrosion resistance describes the material's ability to prevent deterioration caused by atmosphere, moisture, or other medium. Wear resistance indicates the ability to prevent surface damage caused by contact with other surfaces. Toughness describes the material's ability to absorb energy before breaking, while hardness (commonly measured as indentation hardness) describes its resistance to permanent surface deformation. Formability indicates how easily the material can be permanently shaped. Machinability describes how easily it can be cut, shaped, finished, or otherwise machined, while weldability characterizes the ability to be welded.