Copper is still one of the oldest metals. This is not surprising given the extraordinary properties of copper materials. In particular, copper has excellent corrosion resistance as well as thermal and electrical conductivity. Therefore, it is valuable for countless applications.
CNC copper machining is one of the most precise metal machining services used in various industries to produce copper parts. However, there are several aspects to consider when machining copper parts.
In this guide, you will learn everything you need to know about CNC copper machining, its applications, and the various factors to consider before machining copper.
CNC makes copper processing easier
Computer-controlled CNC machines are among the most sought-after manufacturing technologies for machining applications. This is due to its high speed, accuracy, precision and compatibility with various materials.
Above all, this machining service has become very common in the production of desired parts in various materials, and copper is no exception. In the past, processing copper was laborious due to its high flexibility, toughness and plasticity.
Still, CNC machining has made machining copper parts much easier. This is all thanks to the automated processes involved in machining the desired copper parts.
Types of Copper Materials for CNC Machining
Copper materials are one of the main groups of commercially available metals. Various grades of copper are widely available for processing copper parts. They also have different properties that are suitable for specific editing projects.
Therefore, choosing the right material for your machining project can be difficult as several factors come into play.
However, identifying the material with the right properties for your copper parts is the first step in processing.
Check out the different types of copper material for CNC machining below:
1. Pure copper
Pure copper materials are generally soft and malleable. The dilute grade of pure copper contains a small amount of various alloying elements. This, therefore, helps to bring one or more basic properties of pure copper into the desired form. Likewise, the addition of other alloying elements to this type of copper increases its toughness.
Commercial grades of pure copper contain a total of about 0.7% impurities in their composition. You will notice that they are marked with UNS numbers C10100 to C13000 depending on the elements added and the level of impurity.
Pure copper is best suited for making electrical appliances. This includes cables and motors. Furthermore, this type of copper is used in industrial machines, such as heat exchangers.
2. Electrolytic copper
Pitch resistant electrolytic copper is created from cathode copper. Cathode copper is copper refined by electrolysis.
Generally, this process involves adding copper compounds to a solution. The copper material is then cleaned by applying sufficient electricity. As a result, most electrolytic copper contains fewer impurities than other types of copper.
You will find that C11000 is the most widely used of all electrolytic copper types. C11000 typically contains less than 50 ppm of metallic impurities, including sulfur. Furthermore, they have high electrical conductivity of up to 100% IACS (International Annealed Copper Standard).
Their exceptional ductility makes them suitable for electrical applications. This includes windings, cables, wires and busbars.
3. Oxygen-free copper
Compared to other types of copper, oxygen-free types of copper have the highest purity. They also contain little or no oxygen. In most cases, oxygen-free types of copper contain many highly conductive copper electrical components. However, C10100 and C10200 are the most common.
- C10100, known as oxygen-free electronics (OFE), is pure copper with an oxygen content of about 0.0005%. Furthermore, it is the most expensive of these types of copper.
- C10200, also called oxygen free (OF), contains about 0.001% oxygen. It also has high electrical conductivity with at least 100% IACS, which is no better than electrolytic copper materials.
These oxygen-free copper materials are manufactured by induction melting using high-quality cathode copper. In this manufacturing process, cathode copper is melted under non-oxidizing conditions guaranteed by a graphite bath covering. This helps to reduce the hydrogen content in the working atmosphere.
Oxygen-free copper alloys are best suited for high-vacuum electronics due to their high conductivity. This includes transmitter tubes and glass-to-metal seals.
4. Copper free cutting
This copper material consists of several alloying elements. Notable elements include nickel, tin, phosphorus and zinc. The presence of these elements helps to improve the machinability of this type of copper.
Cutting materials also include copper alloys such as bronze and brass. The following must be taken into consideration:
- Bronze is an alloy of copper, tin and phosphorus known for its hardness and impact resistance.
- Brass is an alloy of copper and zinc with exceptional workability and corrosion resistance.
Machine-machinable copper materials are suitable for a wide range of copper parts processing. This includes coins, flashlights, machined electrical components, gears, bearings, automotive hydraulics, etc.
Advantages and Disadvantages of CNC Copper Parts
Most CNC copper parts available today have specific advantages and disadvantages. Check it out below:
Benefits
In general, most CNC copper parts feature good machinability, ductility and impact resistance. They also have high thermal and electrical conductivity, resistance to corrosion and wear.
Another advantage of CNC machining of copper parts is good formability in both hot and cold processes. Furthermore, CNC copper parts are compatible with various cost-effective surface treatments.
Disadvantages
Despite the general advantages, CNC machining of copper parts also has some disadvantages. For example, not all copper materials can be subjected to processes such as spot welding, coated metal arc welding, etc.
Furthermore, different types of copper have different corrosion resistance properties. Therefore, some CNC copper parts are susceptible to corrosion in atmospheres with reactive substances.
Factors to Consider in CNC Machining of Copper
CNC copper parts continue to be in high demand. However, there are some important factors that must be considered before machining copper parts. Check out some of these factors below:
1. Selecting the right type of copper material
Before CNC machining copper, you must select the correct type of copper that is best suited for your application. For example, choosing pure copper to produce mechanical parts is inappropriate and expensive. Due to its excellent machinability, free-cutting copper is the most suitable.
Furthermore, they are also cost-effective. Therefore, you need to check the required properties of your copper parts to choose the right type of copper for machining.
2. Design for Manufacturability
You also need to consider project requirements and specifications before machining copper. This allows you to get the functionality you need from your fabricated copper part.
As a general rule, a wall thickness of 0.5 mm is ideal and must be adhered to to produce aesthetically pleasing copper parts.
Additionally, you can also use some proven construction methods. This includes reducing the number of part assemblies, dimensional inspections and avoiding deep pockets with small radii.
3. Set the adjustment feed rate
Feed rate is the speed at which the cutting tool engages the workpiece. Therefore, before processing copper parts, it is necessary to set the correct feeding speed, as this affects the quality, service life and surface finish of the copper part. Additionally, copper conducts heat quickly. A high feed rate can therefore increase tool wear over time.
4. Choose the right material for the tool
Many types of copper have different workability and strength. Therefore, selecting the appropriate tool material for machining copper parts is crucial. Additionally, you will find that CNC steel machining is used in the production of high-speed cutting tools for copper machining. This helps prevent complications such as tool wear and chip formation.
Surface finishing and post-processing options for copper parts
As the name suggests, surface finishing is a process carried out after manufacturing metal parts. In general, these post-processing operations aim to modify the surface of copper pieces to give them certain characteristics and make them more attractive.
Below are the standard surface treatments for copper parts.
Electropolishing
Electropolishing removes a microscopic layer of material from the surface of copper parts. This material is typically between 0.00254 mm and 0.0635 mm wide. This finishing method helps to make the surface of the finished copper piece smoother and shinier.
Additionally, electropolishing can help improve the corrosion resistance of finished copper parts.
Electroplating
The galvanic copper coating additionally protects the outer surface of the copper parts against oxidation. The metal plates are applied without affecting their electrical and thermal conductivity. Therefore, this process helps to extend the life of your copper parts.
Rays
This post-processing method helps hide flaws in manufactured copper parts. Furthermore, sandblasting produces a more durable, opaque and subtle finish.
Techniques for processing copper parts
Many industries use various metalworking services to produce metal parts, but some machining techniques are only suitable for certain metal materials. You will agree that machining pure copper can be more challenging than machining brass.
As a copper alloy, brass contains other alloying elements such as zinc, making it much easier to machine than most metallic materials. Therefore, you can process copper alloys using several techniques.
Check out some of the techniques suitable for machining copper parts below:
Milling for copper parts
CNC milling is an automated machining process that controls the movement and feed rate of rotating cutting tools. When CNC milling copper, the tools rotate and move over the surface of the copper material. Excess copper material is then slowly removed until the desired shape and size is achieved.
CNC milling is most commonly used on copper alloys because they are more machinable and produce precise, complex parts. Manufacturers often use 2 flute carbide end mill to mill copper.
Additionally, experts use this process to create a variety of design features for copper parts. These include, for example, notches, pockets, holes, grooves, grooves, surfaces, contours, etc.
Turning of copper parts
This manufacturing process requires copper materials to be fixed in one position. Furthermore, the cutting tools fed into the workpiece remain stationary. Therefore, at the correctly set speed, the rotating copper material will be reduced to the desired size.
Turning is suitable for many copper alloys and allows the rapid production of high-precision copper parts. Furthermore, this process is also economical. Therefore, CNC copper turning is suitable for the production of many electronic and mechanical components, such as electrical cable connectors, valves, busbars, radiators, etc.
Copper CNC Machining Applications
Copper CNC parts are valuable in several industries, including electrical, construction, transportation and consumer goods.
Below are the applications of CNC copper machining:
- Heat exchanger
- Electrical connections
- radiator
- Bearings and gears
- Gas welding nozzles, etc.
Copper machining services at WayKen
CNC copper parts are suitable for many different applications today. However, to meet the specifications and design requirements of these copper parts, quality copper machining services are essential.
Contact us today for personalized support service and receive a response within 12 hours.
Common questions
What is the cutting speed of copper?
You can apply different cutting speeds for copper materials. However, please note that this depends on the quality of the copper and the processing method. For example, when milling brass, a standard cutting speed of 2,000 to 4,000 fpm is used.
Can copper be finely ground?
The ease of milling copper depends on the quality of the copper material you are working with. You will find that pure copper is a difficult metal to work with due to its high malleability and strength. In contrast, copper alloys like brass are much easier to mill due to their greater machinability.
Which copper alloy element is suitable for high speed machining?
By alloying copper with elements such as zinc, tin, nickel, aluminum and silicon, the material can be better processed. Therefore, it is suitable for high-speed machining.
