Nylon and POM (polyoxymethylene, also known as acetal or Delrin) are two of the most important engineering plastics. Both are widely used for precision mechanical components, but their distinctly different properties make each better suited for specific applications.
Mechanical Properties Head-to-Head
| Property | PA6 (Nylon) | POM (Acetal) |
|---|---|---|
| Tensile Strength (MPa) | 70-85 | 60-70 |
| Flexural Modulus (GPa) | 2.5-3.0 | 2.6-2.9 |
| Elongation at Break (%) | 50-150 | 25-75 |
| Density (g/cm³) | 1.14 | 1.41 |
Wear and Friction: A Critical Difference
POM’s key advantage over nylon is its excellent wear resistance and low coefficient of friction (0.2-0.35 against steel), making it preferred for gears, bearings, and sliding components.
Moisture Absorption
POM absorbs less than 0.3% water even at saturation, while nylon absorbs 2.5-9.5% depending on conditions. This means POM parts maintain consistent dimensions regardless of humidity.
Chemical Resistance
Nylon is resistant to oils, greases, fuels, and alkalis. POM offers excellent resistance to organic solvents, oils, and neutral chemicals but is attacked by strong acids.
Thermal Properties
| Property | PA6 | POM |
|---|---|---|
| Melting Point (°C) | 220 | 165-175 |
| HDT at 1.8 MPa (°C) | 65 | 95-110 |
| Continuous Use Temp (°C) | 80-100 | 90-100 |
Application Guide
Choose Nylon When:
- Impact resistance and toughness are critical
- Parts experience dynamic loading
- Higher temperature resistance is needed (PA66)
Choose POM When:
- Dimensional stability in varying humidity is critical
- Low friction and wear resistance are priorities
- Parts operate in wet environments
- Precision mechanical components are needed
Our Capabilities
With over 300 CNC machines, we produce more than 10,000 pieces daily with tolerances as tight as ±0.005mm. We accept MOQ from 1 piece, with delivery times ranging from 24 hours to 15 days. We machine both nylon and POM for precision applications. Get a quote within 24 hours.
Frequently Asked Questions
Can POM replace nylon in gears?
Often yes—and it’s frequently the better choice. POM’s low friction and excellent dimensional stability make it ideal for precision gears, especially in wet environments.
Why is POM heavier than nylon?
POM has a density of approximately 1.41 g/cm³ versus nylon’s 1.14 g/cm³—about 24% heavier. This is due to POM’s highly crystalline structure.
Does nylon require lubrication while POM does not?
POM can operate without external lubrication in many applications due to its self-lubricating properties. Nylon benefits from lubrication under high loads.
Which material is easier to machine?
Both machine well, but POM generally produces better surface finishes and tighter tolerances due to its dimensional stability.
