Aluminum is suitable for many different applications because of its light weight, corrosion resistance, and thermal and electrical conductivity. It is commonly utilized to make very precisely machined plates for fabricating seals, brackets, and sills used in manufacturing processes to secure parts within tolerances or allow precisely engineered movements of machined components. Fabricating these high-precision parts requires materials that machine cleanly and with minimal deformation.

In this post, we’ll identify some especially machinable aluminum alloys, their unique properties, and the applications these alloys are suitable for.

2011 Aluminum: Free Machining Performance

2011 aluminum is considered the most machinable of all commonly available aluminum alloys. It is designed to cut quickly and easily and produces an excellent surface finish. Along with its good mechanical properties, this makes it an excellent choice for machinists looking for an aluminum alloy that can be machined quickly and precisely.

2011 aluminum is a free machining grade, which means it produces fine, broken chips rather than the long, stringy chips of softer aluminum alloys. These small chips are easily removed and less likely to get tangled or stuck, making 2011 easy to machine without the need for close supervision and constant adjustments. For this reason, it is commonly used with repetitive, automated machining processes.

2011’s excellent machinability and ability to handle high machining speeds make it a great material for complex parts with precise details. Some examples include:

• Appliance parts and trim.
• Automotive trim.
• Brackets.
• Fasteners.
• Fittings.

However, 2011 has very little corrosion resistance, so parts typically need to be anodized to protect them from corrosion. Also, while its strength is adequate for many cases, there are stronger aluminum alloys that may be better suited for mechanically demanding applications.

6061 Aluminum: Versatile and Machinable

Sometimes referred to as “structural aluminum,” 6061 is the most commonly used aluminum alloy. Its versatility comes from its strength, corrosion resistance, heat treatability, easy machinability, and weldability. Like 2011 aluminum, it can also be anodized, adding extra corrosion protection to finished parts.

6061 aluminum is a popular material for a wide variety of manufacturing applications because it can be readily worked by almost any technique, including machining, welding, and forming. It is used for construction, automotive and marine parts, bicycle frames, furniture, electrical fittings, couplings, valves, seals, and countless other products and applications. Structural components such as flooring, ramps, stairs, fixtures, brackets, and sills are commonly fabricated with 6061 aluminum plate machining.

As one of the most versatile and commonly available aluminum alloys, 6061 is a safe choice for most machining applications. If you need a good all-around alloy for aluminum plate machining and you’re not sure which alloy to use, 6061 will likely suit your needs.

Aluminum Tooling Plate: Precision Aluminum Plate Machining

For the most high-precision machining applications, aluminum tooling plate is the best choice. These cast plates are heat-treated to remove internal stresses and precision-machined to very tight tolerances, with flatness tolerances as low as .005” and surface roughness of 32 μin.

The fine grain structure of the alloys and the stress-relieving heat treatment they receive give the aluminum tooling plate very low porosity and excellent dimensional stability. These plates can be machined to a high level of precision, as the machining process will not move or deform them.

There are various aluminum tooling plate products available, and they all share similar properties. Some common tooling plates include:

• MIC-6.
• ACP 5080.
• ATP-5.
• K-100S.
• Alca-5.

Cast aluminum tooling plate is suitable for applications requiring a high level of precision in flatness, thickness, and/or surface finish, such as the following:

• CNC routing tables
• Jigs
• Fixtures
• Molds
• Inspection gages
• Aircraft and automotive tooling
• Electronics
• Food machinery

Aluminum Plate Available from Your Local Metal Supplier

For more than two decades, Industrial Metal Service has served the San Francisco Bay Area as a trusted name in new and remnant metal sales. Our customers range from hobbyists and craftspeople to major manufacturing companies.

We stock a variety of aluminum alloys in our San Jose warehouse, including 6061 aluminum and MIC-6 tooling plate. With our precision MetlSaw—one of the best aluminum plate cutting saws on the market—we can provide precision-cut plates in virtually any size while holding the tightest tolerances.