CNC machining commonly used engineering plastics can be applied to a variety of plastic materials, ranging from soft polyethylene (PE) to rigid POM and PC. Compared to metal machining, the main differences lie in tool selection and machining parameters, such as cutting speed and cutting depth.
The following list includes characteristics, machining properties, and surface finishing options
- PS
- PVC
- ABS
- PC
- PP
- PBT
- PEI
- POM
- Acrylic (PMMA)
- Nylon (PA)
- Polyethylene (HDPE and LDPE)
- Polyester
- PTFE (Teflon)
PS (Polystyrene), commonly known as Styrofoam
Polystyrene is a colorless and transparent thermoplastic. Expanded polystyrene is commonly referred to as Styrofoam. It has a glass transition temperature above 100°C, making it widely used for disposable containers that need to withstand boiling water temperatures, such as foam lunch boxes.
Material Characteristics:
- High rigidity, transparent or opaque
- Brittle and prone to cracking
- Good electrical insulation properties
Description:
Polystyrene is a lightweight and rigid thermoplastic commonly used in lightweight product manufacturing. Although it has low mechanical strength, it is easy to process and suitable for precision machining applications.
Applications:
- Packaging materials
- Optical lenses, lampshades
- Electronic product casings
- Low-load mechanical components
PVC (Polyvinyl Chloride)
Material Characteristics:
- Excellent chemical resistance
- Flame retardant properties
- High rigidity but low toughness
Description:
PVC is a widely used plastic, available in both rigid and flexible forms. Rigid PVC offers high impact resistance, while flexible PVC is more elastic.
Applications:
- Pipes and fittings
- Wire and cable sheathing
- Building materials (window frames, flooring)
- Industrial equipment enclosures
ABS (Acrylonitrile Butadiene Styrene)
Material Characteristics:
- High strength, impact resistance
- Good machinability, suitable for CNC machining and 3D printing
- Moderate chemical resistance
Description:
ABS has excellent mechanical properties and dimensional stability, making it widely used in various industrial and consumer products.
Applications:
- Automobile parts (interior components, dashboards)
- Toys (LEGO bricks)
- Electronic casings (laptops, phone cases)
- Household appliances (vacuum cleaners, coffee machines)
PC (Polycarbonate)
Polycarbonate is a colorless, transparent, amorphous, thermoplastic polymer whose molecular chain contains carbonate groups. The name is derived from the presence of CO₃ groups in its structure. Polycarbonate is classified into aliphatic, aromatic, and mixed types, with aromatic polycarbonate (such as bisphenol A polycarbonate) being the most widely used.
Material Characteristics:
- High strength, high toughness
- Excellent transparency and impact resistance
- Good heat resistance
Description:
PC is renowned for its outstanding impact resistance and optical properties, making it ideal for applications requiring high strength and transparency.
Applications:
- Bulletproof glass
- Safety helmets and goggles
- Lighting lenses
- Electronic device enclosures
Material Properties:
- High rigidity and good dimensional stability
- Strong heat and chemical resistance
- Low water absorption
Description:
PBT is an engineering plastic commonly used in electronic components and mechanical parts that operate in high-temperature environments.
Applications:
- Electronic connectors
- Automotive electrical components
- Mechanical gears and housings
PEI (Polyetherimide)
Polyetherimide is an amorphous, amber to transparent thermoplastic, with properties similar to PEEK. When compared to PEEK, PEI is more affordable but has lower impact strength and a narrower temperature range. PEI plastic was first introduced to the market by General Electric in 1982 under the trade name Ultem. Due to its adhesive properties and chemical stability, it has become a popular bed material for FFF 3D printers.
Material Properties:
- High strength and heat resistance
- Excellent electrical insulation
- Good chemical resistance
Description:
PEI offers exceptional mechanical properties and heat resistance, making it suitable for high-demand industrial applications.
Applications:
- Aerospace components
- Electronic insulation materials
- Medical equipment
POM (Polyoxymethylene, Acetal)
Polyoxymethylene (POM), also known as polyacetal, acetal, or Delrin, is a thermoplastic used in engineering applications requiring high rigidity, low friction, and excellent dimensional stability.
Typical injection molding applications of POM include high-performance engineering components such as small gears, fasteners, knife handles, and locking devices. The material is widely used in the automotive and consumer electronics industries. Some components of the M16 assault rifle are also made from it.
Material Properties:
- High hardness and rigidity
- Low friction coefficient, wear-resistant
- Good dimensional stability
Description:
POM, commonly known as acetal, is a wear-resistant engineering plastic ideal for precision parts and mechanical components.
Applications:
- Gears and bearings
- Automotive fuel system components
- Industrial valves and pumps
Material Properties:
- High transparency, can replace glass
- Good weather resistance, not easy to yellow
- High hardness but relatively brittle
Description:
PMMA has excellent optical properties, suitable for transparent and decorative applications.
Applications:
- Lampshades and display racks
- Advertising signs and signboards
- Optical lenses
PA (Nylon)
Polyamide (English: Polyamide, PA) is a polymer formed by the polymerization of monomers containing carboxyl and amino groups through amide bonds. This polymer can occur naturally (such as in wool and silk from natural proteins) or be artificially synthesized through stepwise polymerization or solid-phase polymerization (such as nylon), or aromatic polyamides and sodium-poly (such as aspartic acid). Due to its extreme durability and strength, synthetic polyamide polymers are commonly used in textiles, carpets, sportswear, food packaging, eyewear parts, automobile and aircraft components, tires, military equipment, and protective gear.
Material Properties:
- High strength, high toughness
- Good wear resistance
- High water absorption, may affect dimensional stability
Description:
Nylon is a high-strength engineering plastic suitable for mechanical structural components.
Applications:
- Gears and bearings
- Ropes and fibers
- Industrial parts
PE (Polyethylene)
Polyethylene (PE) is one of the most commonly used plastics in daily life, widely used for making plastic bags, films, barrels, and other products. It is also the major type of plastic waste on Earth today.
Material Properties:
- Soft yet tough, excellent wear resistance
- Low water absorption, strong chemical resistance
- Low friction coefficient
Description:
PE is classified into High-Density Polyethylene (HDPE) and Low-Density Polyethylene (LDPE), widely used in various applications.
Applications:
- Pipelines and water tanks
- Food packaging
- Industrial liners
Polyester (PET, PBT)
Polybutylene Terephthalate (PBT) is commonly used in electrical engineering as an insulation material. In the automotive industry, it is used for connector plugs. In household applications, it is found in showerheads and iron handles. Additionally, it can be spun into fibers for use in toothbrushes and cosmetic brushes.
Material Properties:
- Excellent heat and chemical resistance
- High mechanical strength
- Low water absorption
Description:
Polyester plastics are widely used in electronics and mechanical fields. PBT is a type of polyester.
Applications:
- Electronic components
- Packaging materials
- Mechanical parts
PTFE (Polytetrafluoroethylene, Teflon)
This material is commonly known for its “non-stick coating” or “easy-clean cookware material.” It is a synthetic polymer where fluorine replaces all hydrogen atoms in polyethylene. It is resistant to acids, alkalis, and organic solvents. PTFE also has excellent heat resistance and an extremely low friction coefficient, making it ideal for non-stick coatings and internal pipe linings.
Material Properties:
- Low friction coefficient, anti-adhesive
- High-temperature and chemical resistance
- Excellent electrical insulation
Description:
PTFE, commonly known as Teflon, is widely used for its non-stick and heat-resistant properties in specialized industrial applications.
Applications:
- Non-stick coatings (e.g., cookware)
- Seals and gaskets
- Insulation materials
These engineering plastics have unique properties suited for different CNC machining needs. When selecting materials, factors such as mechanical performance, chemical resistance, and heat resistance should be considered.
Yong Yi Technology Co., Ltd.