CNC machining is a common process used to create parts from metal. However, CNC machining can also be used to create parts from plastic. Plastic CNC machining is a popular process in several industries due to the wide range of plastic CNC materials available. Additionally, the introduction of computer numerical control (CNC) has made the process more accurate, faster, and suitable for creating parts with tight tolerances.

 

8 common CNC processing materials

Many machinable plastics are suitable for manufacturing parts and products in several industries. Their use depends on their properties, with some machinable plastics, such as nylon, having excellent mechanical properties that allow them to replace metals. Below are the most common plastics for custom plastic machining:

 

1.PVC

Polyvinyl chloride, or PVC, is a versatile CNC material that is available in a variety of grades and formulations. It is known for its strength, durability, and resistance to chemicals and moisture. PVC is also relatively inexpensive, making it a popular choice for a wide range of applications.

 

Pros

PVC is a strong and durable material that is resistant to chemicals and moisture.

It is available in a variety of grades and formulations, making it suitable for a wide range of applications.

PVC is relatively inexpensive, making it a cost-effective option.

It is easy to machine, making it a good choice for rapid prototyping and production.

 

Cons

PVC can be difficult to work with due to its high stiffness.

It is not as heat resistant as some other CNC materials.

PVC can release harmful fumes when heated, so it is important to use proper ventilation when working with it.

 

Applications

PVC is used in a wide range of applications, including:

• Automotive
• Building and Construction
• Medical devices
• Packaging
• Pipes and fittings
• Consumer products

 

PVC is a versatile and affordable CNC material that is suitable for a wide range of applications. Its strength, durability, and resistance to chemicals and moisture make it a good choice for many industries.

 

2.PEEK

Polyether ether ketone, or PEEK, is a high-performance engineering thermoplastic that is known for its strength, toughness, and chemical resistance. It is also a good electrical insulator and has excellent wear resistance. PEEK is often used in applications where high temperature and chemical resistance are required, such as in the aerospace, medical, and automotive industries.

 

Pros

PEEK is a strong and tough material that is resistant to a wide range of chemicals and solvents.

It has excellent wear resistance and is a good electrical insulator.

PEEK is also a good choice for applications where high temperatures are required, as it can withstand temperatures up to 260 °C.

PEEK is easy to machine and can be used in a variety of CNC machining processes.

 

Cons

PEEK is a relatively expensive material.

It can be difficult to work with due to its high stiffness.

PEEK can release toxic fumes when heated, so it is important to use proper ventilation when working with it.

 

Applications

PEEK is used in a variety of applications, including:

Aerospace

Medical

Automotive

Chemical processing

Oil and gas

 

PEEK is a high-performance engineering thermoplastic that is suitable for a wide range of applications. Its strength, toughness, chemical resistance, and wear resistance make it a good choice for demanding applications.

 

3.PTFE

Polytetrafluoroethylene, or PTFE, is a high-performance thermoplastic that is known for its non-stick properties, chemical resistance, and low friction. It is often used in applications where these properties are essential, such as in the food processing, medical, and aerospace industries.

 

Pros

PTFE is a non-stick material that is resistant to a wide range of chemicals and solvents.

It has excellent wear resistance and low friction, making it a good choice for applications where parts need to move smoothly against each other.

PTFE is also a good insulator and is resistant to heat and electricity.

PTFE is easy to machine and can be used in a variety of CNC machining processes.

 

Cons

PTFE is a relatively expensive material.

It can be difficult to work with due to its high stiffness.

PTFE can release toxic fumes when heated, so it is important to use proper ventilation when working with it.

 

Applications

PTFE is used in a variety of applications, including:

Food processing

Medical devices

Aerospace

Chemical processing

Oil and gas

 

PTFE is a high-performance thermoplastic that is suitable for a wide range of applications. Its non-stick properties, chemical resistance, low friction, and heat resistance make it a good choice for demanding applications.

 

4.Polyester ether elastomer (POM)

POM is an engineering plastic known for its heat resistance, chemical resistance, mechanical properties and electrical properties. Although it excels in mechanical properties, it has shortcomings in chemical stability and is susceptible to grease, alcohols, and other chemical solvents. Additionally, pure POM (POM without additives) has lower thermal stability and the plastic polymer will still burn after the flame is removed.

 

PROS

- Low density but high mechanical strength

- Easy to process, one of the popular materials for rapid prototyping

- Low melting point, suitable for rapid prototyping processes such as 3D printing and injection molding

- high strength

- Long life and good durability

- The price is relatively cheap

 

CONS

- Heating will release toxic thermoplastic fumes and ventilation is required.

- Low melting point, heat generated by CNC machine may cause deformation

 

Application

- Auto parts such as gears, bearings, etc.

- Electronic components such as motors, switches, etc.

- Medical equipment such as catheters and tubes

- Electrical appliances such as microwaves and washing machines, etc.

- Packaging materials such as caps and seals

 

Generally speaking, POM is a widely used high-quality engineering plastic that is widely used in industries such as electrical appliances, automobiles, and medical equipment due to its advantages of heat resistance, chemical resistance, mechanical strength, and easy processability.

 

5.Polycarbonate (PC)

PC is known for its high transparency, high heat resistance, and excellent mechanical and electrical properties. Although it performs well in terms of mechanical properties, it has shortcomings in chemical stability and is susceptible to acidic solvents. In addition, the thermal stability of pure PC (PC without additives) is average, and plastic polymers may deform at high temperatures.

PROS

- high transparency

- High heat-resistant temperature, can withstand high temperatures of 100°C for a long time

- High mechanical strength

- Good weather resistance and stable color

-Excellent electrical properties

 

CONS

- Affected by acidic solvents

- Thermal stability is average and may deform at high temperatures.

- higher cost

 

Application

- CD, DVD and Blu-ray discs

- Display and TV casing

- Lighting fixtures

- Electrical housing

- Transparent pipes and storage boxes

 

Generally speaking, PC materials are widely used in optical devices and electronic products due to their high transparency, high heat resistance, and excellent mechanical and electrical properties. However, its chemical stability and thermal stability need to be strengthened. Affected by acidic solvents, it may deform at high temperatures. In addition, the relatively high cost of PC materials also limits its application in more fields.

 

6.Polyurethane (PU)

PU is widely used due to its diverse mechanical properties, wear resistance and ease of processing. It has good durability, wear resistance and weather resistance. However, PU has poor thermal stability, and long-term high temperatures will lead to a decline in physical properties.

 

PROS

- Various mechanical properties

- Good wear resistance

- Easy to process into various shapes

- The price is relatively cheap

 

CONS 

- Poor thermal stability, high temperatures will lead to performance degradation

- Odor may occur after processing

 

Application

- Auto parts such as tires, gaskets, etc.

- Footwear materials

- Housings for household appliances

- Industrial coating

- Medical device gaskets

 

PU materials are widely used in automobiles, footwear, home appliances and other fields due to their diverse mechanical properties, excellent wear resistance and easy processability. However, its thermal stability is poor, and long-term high temperatures will lead to performance degradation. In addition, the possible odor after processing is also a certain limitation of its application. But generally speaking, PU materials are cheap and have a wide range of applications.

 

7.Nylon (PA)

PA is characterized by its high strength and easy processing. It has excellent mechanical properties and chemical stability, but average thermal stability. In addition, the mechanical strength of PA material is greatly affected by processing conditions and profile structure.

 

PROS

- High mechanical strength

- Good weather resistance and chemical stability

- Easy to process and shape

- Relatively cheap

 

CONS

- Average thermal stability

- Mechanical strength is greatly affected by processing technology

- Bad impact on the environment

 

Application

- Electrical housing

- Home appliance components

- Automotive interior parts

- Cable housing

- Daily necessities

 

PA materials are widely used in electronics, electrical appliances, automobiles and other products due to their high strength, easy processing, excellent mechanical properties and chemical stability. However, it still needs to be improved in terms of thermal stability and mechanical strength being affected by processing conditions. In addition, PA materials may have a certain impact on the environment during the production process and limit their application in more fields. But generally speaking, PA materials are cheap and have broad application prospects.

 

8.ABS (acrylonitrile-butadiene-styrene)

ABS (acrylonitrile-butadiene-styrene) material is widely used in casings and structural components of electrical appliances, electronics, automobiles and other products due to its good mechanical properties, easy processability and excellent impact resistance.

PROS

• High strength, impact strength as high as 50-100J/m, 4-5 times stronger than resin materials of the same specifications. This makes it a good choice for enclosures for appliances and electronics.
• It has good processability and can be processed into various complex structures through extrusion molding, injection molding and other methods to meet the needs of product design.
• The surface is smooth and good appearance can be achieved without painting. This simplifies the production process.
• The price is cheap, the cost is about 2/3 of PC material, which is very beneficial for mass production.
• Rich in color, different colors of fillers can be added as needed, making it highly aesthetically pleasing.

 

CONS

• Poor thermal stability, long-term high temperature will lead to performance degradation. This limits its application in scenarios requiring high heat loads.
• It is greatly affected by solvents and is easily corroded by acids and ester solvents, affecting its service life.
• It is heavier, with a density of 1.05g/cm3, which is about 20% heavier than PC materials of the same strength.

 

Generally speaking, ABS materials will still be widely used in areas such as electrical casings and automotive interiors due to their low cost, easy processing, and excellent mechanical properties. However, its thermal stability and chemical stability need to be further improved to expand its application range.