Plastics, Engineering PlasticsAcetal Bar (POM)

A general purpose, semi-crystalline, engineered thermoplastic with high mechanical strength.

Acetal has a unique balance of physical properties not available in most other thermoplastics. This copolymer acetal is an engineering plastic made for wide-ranging universal applications in many different industries. The key performance characteristics of unmodified POM copolymer include high mechanical strength and rigidity, excellent wear, low moisture absorption and excellent dimensional stability. It also offers high crystallinity and a good degree of toughness (even in the lower temperature range), combined with good chemical resistance.

Acetal rod is one of the best machining engineering plastics. It makes the machining process very easy by chipping rather than creating a continuous length of swarf that often wraps around tooling. By using very sharp cutting tools that are designed similar to smoothing tools, acetal rod can be machined to an outstanding surface finish with machining marks barely visible.

Acetal is ideal for close tolerance part, excellent for any application where food is involved and the perfect choice for components that are expected to work in damp or wet conditions.

Talk to an expertDownload PDF


Product FormImperial SizesMetric Sizes
Round Bar12" - 2"4.0mm - 250.0mm
If you do not see what you are looking for, please contact your local service centre with your specific requirements.


Properties are for natural bar.

PropertyParameterTest MethodValue
Mechanical Properties
Tensile Strength50mm/minDIN EN ISO 527-2679 MPa
Elongation at Break50mm/minDIN EN ISO 527-232%
Modulus of Elasticity1mm/minDIN EN ISO 527-22800 MPa
Charpy Impact Strength (Notched)max. 7.5JDIN EN ISO 179-1eA8 kJ/m²
Ball Indentation HardnessISO 2039-11654 MPa
Flexural Strength2mm/min, 10 NDIN EN ISO 17891 MPa
Compression Modulus5mm/min, 10 NEN ISO 60423000 MPa
Thermal Properties
Service TemperatureShort termNN140 °C
Service TemperatureLong termNN100 °C
Melting TemperatureDIN EN ISO 11357166 °C
Thermal ConductivityISO 22007-4:20080.39 W/(k*m)
Specific Heat1.4 J/(g*K)ISO 22007-4:2008
Electrical Properties
Volume ResistivityDIN IEC 600931013 Ohm*m
Surface ResistivityDIN IEC 600931014 Ohm
Dielectric StrengthISO 60243-149 kV/mm
Resistance to Tracking (CTI)DIN EN 60112600 V
Other Properties
Water Absorption24h/96h (23 °C)DIN EN ISO 621.8%
FlammabilityUL 94DIN IEC 60695-11-10HB
Density1.41 g/cm³


  • Sliding applications
  • Excellent design solutions with snap fastenings
  • Sliding parts such as bearing bushes, rollers and slide rails
  • Electrical insulating parts
  • Components with contact to water
  • Scratch proof high-gloss exposed parts
  • Wide range of components in the food, pharmaceutical and drinking water industries and in medical technology


  • High strength, rigidity and toughness
  • Good impact strength, even at low temperatures
  • Low moisture absorption (at saturation 0.8%)
  • Outstanding wear resistance and sliding properties
  • Excellent machinability
  • Good creep resistance
  • High dimensional stability
  • Good resistance to hydrolysis (up to ~60 °C)
  • Excellent resilience/recovery elasticity

Find your local Service Centre

An extensive UK network of Service Centres, backed up by a central distribution facility.

  • Experienced multi-product specialists

  • In-house state of the art processing facilities

  • Large fleet of bespoke delivery vehicles

RBL Truck Retouched