What makes CNC machines so unique and widely used in a broad range of industries?
Product designers looking to turn their product idea into reality often ask this question. And the answer goes beyond the high accuracy and precision that CNC machines offer.
Without a doubt, accuracy and precision are essential criteria when choosing any machining technology. But what sets CNC machines apart from other machining technologies is their compatibility with a broad range of engineering materials, including aluminum.
But just because CNC machines simplify aluminum machining, it doesn’t mean fabricating aluminum parts is any less complex than it used to be. There are many aluminum grades (or alloys) available in the market today, and the success of your project will depend on you choosing the most suitable aluminum alloy for your project.
This article presents seven aluminum grades commonly available in the market today, including their properties, advantages, and suitability for different design requirements. It will serve as a guide to help you make the right choice for your project.
Some Benefits and Drawbacks of Aluminum for CNC Machining
Here are some of the benefits of aluminum for CNC machining.
- Good Machinability: Aluminum is easier to machine than many other metals. It chips easily, making it easy for CNC machine operators to create complex parts quickly and accurately.
- High corrosion resistance: Aluminum develops a thin hard film of oxide (aluminum oxide) when exposed to air or other oxidizing agents. This oxide makes aluminum corrosion-resistant and prevents chemical damage.
- High strength-to-weight ratio: Given its high strength, aluminum is remarkably light. As such, you can make aluminum parts thicker and stronger while still reducing weight in applications that require lightweight materials.
- Recyclability: Aluminum has high recyclability, making it perfect for businesses looking to mitigate the material wastage challenge of CNC machining.
- Custom Finishing: Aluminum offers a wide range of surface finishing options, including anodizing and painting, to give your parts the perfect custom look (Related Post: Why Choose an Anodized Finish for Aluminum?)
Like with many other engineering materials, aluminum has its drawbacks. Here are the disadvantages of aluminum for CNC machining:
- Machining Difficulty: Aluminum can be difficult to machine due to its relatively low melting temperature, and its oxide coating can sometimes damage tooling.
- Cost: The energy costs involved in machining aluminum parts are somewhat high, making them more expensive.
7 Aluminum Grades for CNC Machining Compared
Table 1 shows seven common aluminum grades with their properties and applications.
Table 1. Aluminum grades for CNC machining compared
| Aluminum Grade | Description | Machining | Strength | Corrosion Resistance | Workability | Applications |
|---|---|---|---|---|---|---|
| Alloy 1100 | Commercially pure aluminum with excellent corrosion resistance, good machinability, and workability. It is also soft and ductile. | Good | Low | Excellent | Excellent | Heat exchanger fins, dials, nameplates, and chemical and food processing industries. It is also suitable for applications that require bending, stamping, and roll forming. |
| Alloy 2011 | A high-strength alloy that machines exceptionally well. The high-speed machining of alloy 2011 produces fine chips that can easily be removed. | Excellent | High | Poor | Poor | Screw machines, precision gears, tube fittings, pipe stems, and precision machine parts like speedometer parts, cameras, and clocks. |
| Alloy 2024 | A heat-treatable aluminum alloy with a primary alloying element of copper. It is generally stronger than most aluminum alloys. | Fair | High | Poor | Poor | Suitable for applications that demand aluminum alloys with high strength-to-weight ratio and fatigue resistance, for example, aircraft wings and fuselage structures. |
| Alloy 3003 | A medium-strength alloy with a primary alloying element of manganese. | Good | Medium | Good | Good | Ductwork, sheet metal work, cooking utensils, food containers, pressure vessels, and chemical equipment. |
| Alloy 6061 | Aluminum 6061 combines great mechanical properties with workability and corrosion resistance to satisfy a broad range of application requirements. | Good | Medium | Excellent | Good | Aircraft and truck frames, electronic parts, chemical equipment, heat exchangers and commercial bridges, and marine components. |
| Alloy 6063 | A medium-strength alloy with manganese and silicon as its primary alloying elements. It has good mechanical properties and is fairly machinable. | Fair | Medium | Good | Good | Suitable for architectural applications like window frames, doors, roofs, railings, shop fittings, and sign frames. |
| Alloy 7075 | A high-strength alloy with a primary alloying element of zinc. It is fairly machinable and has high fatigue resistance. | Fair | High | Average | Poor | Aerospace parts like aircraft wings, fuselage structures, gears, and shafts. |
Is Aluminum the Right Choice for Your Project?
As you may have realized, aluminum offers several desirable properties and is easily machinable using CNC machines. But is aluminum the right choice for your product design project?
If you’re looking for a readily available metal with a high strength-to-weight ratio and good machinability, aluminum could be the right choice for your project. In addition, you should opt for aluminum if your part or component will be exposed to moist environments since aluminum alloys are generally resistant to corrosion.
But even after you take the plunge with aluminum for your project, you still need a high level of CNC machining expertise to create your parts accurately and precisely.
Gensun Precision Machining is a leading provider of CNC machining services across the globe. We have a team of highly qualified engineers, machinists, and quality control experts capable of creating aluminum parts accurately and precisely.
Learn more about our CNC machining services.
