What is CNC Machining?
CNC Machining is an established digital manufacturing process that produces high-accuracy parts with excellent physical properties directly from a CAD file. Although it’s been around since the early 50’s, recent technological advancements in digital supply chains have reduced the cost of CNC machining drastically and made it easily available to more professionals.
For CNC machining projects, aluminum is one of the most popular material choices for cnc machining parts due to its desirable physical properties. It is strong, which makes it ideal for mechanical parts, and its oxidized outer layer is resistant to corrosion from the elements. These benefits have made aluminum parts common across all industries, though they are particularly favored in the automotive, aerospace, healthcare and consumer electronics spheres.
Aluminum also offers specific advantages that simplify and improve the process of CNC Machining. Unlike many other metals with similar material properties, aluminum offers excellent machinability: many of its grades can be effectively penetrated by cutting tools, chipping easily while being relatively easy to shape. Because of this, aluminum can be machined more than three times faster than iron or steel.
Table of Contents of This Article
Benefits of aluminum CNC machining
1. Machinability
2. Corrosion resistance
3. Strength-to-weight ratio
4. Electrical conductivity
5. Anodization potential
6. Recyclability
1. Machinability of aluminum CNC Machining
The main reasons why engineer choose aluminum for the machined parts are:
1. Aluminum material is easy and simple to be machined, then it would be easy to be manufactured with different design shape.
2. Aluminum raw material is cheaper than other metal “steel, brass, titanium”.
3. Aluminum machining speed is faster than other metal materials with its easy machinability feature.
In general, aluminum cnc machining is easier, simpler, faster, cheaper than other iron or steel metal materials with high precision (tolerances as low as ±0.025 mm) for your custom parts.
2. Corrosion resistance
Different aluminum grades differ greatly in their resistance to corrosion — the degree to which they can withstand oxidization and chemical damage. Fortunately, some of the most popular grades for CNC machining are the most resistant. 6061, for example, offers excellent corrosion resistance, as do other alloys on the lower end of the strength spectrum. (Strong aluminum alloys may be less resistant to corrosion due to the presence of alloyed copper.)
3. Strength-to-weight ratio
Aluminum has desirable physical properties that make it ideal for both mechanical and aspect parts. Two of the most important are the metal’s high strength and its lightweight, both of which make the material favorable for critical parts such as those required in the aerospace and automotive industries. Aircraft fittings and automotive shafts are two examples of parts that can be successfully machined with aluminum.
However, different grades of aluminum serve different purposes. Because of their favorable strength-to-weight ratio, general-use grades like 6061 can be used for a wide variety of parts, while notably high-strength grades like 7075 may be preferred in aerospace and marine applications.
4. Electrical conductivity
CNC machined aluminum parts can be made for electrical components with its good electrical conductivity. Although it is not as conductive as brass copper material, pure aluminum has an electrical conductivity of about 37.7 million siemens per meter at room temperature 24 +/-4℃.
5. Anodization potential
Machined aluminum parts are especially popular in the consumer electronics industry, not just for strength and weight demands, but because of important aesthetic considerations. As well as being receptive to paints and tints, aluminum can be treated with anodization, a surface finishing procedure that thickens the protective and oxidized outer layer of the part.
The anodization process, which generally takes place after machining is completed, involves passing an electric current through the part in an electrolytic acid bath and results in a piece of aluminum that is more resistant to physical impact and corrosion.
Importantly, anodizing makes it easier to add color to a machined aluminum part, since the anodized outer layer is highly porous. Dyes can find their way through the porous sections of the outer layer and are less likely to chip or flake since they are embedded within the tough exterior of the metal part.
6. Recyclability
Another benefit of aluminum is its high recyclability, which makes it preferable for businesses seeking to minimize their environmental impact or for those who simply want to reduce material wastage and recoup some of their expenditure. Recyclable materials are particularly important in CNC machining, where there is a relatively large amount of waste material in the form of chips from the cutting tool.
How much cost of CNC Machining Aluminum
We will take a look into the cost details of CNC machining aluminum (including design, machinery, labor and raw material costs), cnc machining aluminum is more accessible than you may think.
Machinery Costs
Aluminum CNC machinery come in different variations. Depending on their machine architecture and capabilities the typical machine per hour differs.
- The typical cost rate of a 3-axis machining cnc milling machinery (including of the operator salary 10$) is 20~30$ per hour.
- The 3-axis CNC Turning is usually priced lower at 20$ per hour because its machinery cost is lower and operation is simpler.
- The average cost of 4 or 5 axis CNC Milling machining from 35$ to 50$ or higher due to its high machinery cost and complex operation.
In general, we should choose a simpler CNC Machinery to manufacture our custom aluminum parts based on the material and part design, also quality requirements, with a rich experience engineer that can help you to define which CNC machining method we should choose to have best cost and good quality, also fast delivery, you can read https://www.3qmachining.com/what-is-cnc-machining/ to have better understanding cnc machining cost list of different type of machines.
Raw Material Costs
Most of materials can be machined by CNC Machining with different custom designs, including of aluminum, titanium, steel, brass, plastic, or wood etc.
The cost of your material is often given per 6″x6″x1″ sheet. The cost of some popular plastics per sheet are:
- ABS costs $17 per block
- POM (Delrin) costs $27 per block
- Nylon 6 costs $30 per block
The cost of some popular metals for CNC machined parts are:
- Aluminum 6061 costs $25 per block
- Aluminum 7075 costs $80 per block
- Stainless steel 304 costs $90 per block
CNC machining, being a subtractive manufacturing technology, has considerable waste as material is removed from the original block.
It’s important to know that you will be charged for the use of a whole aluminum steel block. Where possible try to make as many parts of your design fit into one block as you can. This will mean you have fewer blocks to use overall and save you some cost in the order.
Labor costs
Labor in CNC machining aluminum is primarily connected to start-up costs (CAM programming, process planning), but these are one time charge costs and are eliminated by higher production volumes.
CNC machining technology has not changed significantly during the past few years. Incremental improvements in machine design, tooling, consumables and CAM software lead to an optimization of the production cycles, improving quality and but not significantly affecting the cost of Aluminum CNC machined parts.
What 3Q Machining can do for you?
3Q Machining is top quality CNC machining manufacturer factory in China for your custom aluminum and other metal/plastic parts from CAD drawing to final shipment with low MOQ, high precision, fast delivery to save your time, save your money.
You are welcome to visit our factory before set up long term business relationship with us!
