POM Green Red Rod Polyoxymethylene Plastic Rod
Mechanical Properties (Ultra-High Rigidity + Low Creep)
The core competitiveness of POM rods lies in their unique balance of "rigidity close to metal + low creep":
Tensile Strength: Homopolymer approximately 60-75 MPa, copolymer approximately 55-70 MPa (approximately 1/3 that of mild steel, but 20%-30% higher than PA6/PET);
Flexural Strength: Homopolymer approximately 90-110 MPa, copolymer approximately 85-100 MPa (capable of withstanding moderate static loads, such as supporting structures);
Elastic Modulus: Approximately 2800-3200 MPa (much higher than the 2000-3000 MPa of PA6/PET and approximately 1/3 that of aluminum alloy), offering exceptional rigidity (resistance to bending and deformation under load);
Compressive Strength: Approximately 120-150 MPa (suitable for bearing axial pressure, such as bearing seats and gear sleeves);
Creep Performance: Under long-term loads (such as continuous pressure or tension), POM exhibits extremely low deformation (less than 1% after 1000 hours, significantly better than PA6/nylon), making it suitable for applications requiring long-term precision (such as precision gears and locating pins).
Typical Applications: POM rods are used to manufacture precision components requiring high rigidity and low deformation (such as gears, sleeves, and guide rods). They maintain their original dimensions even under long-term loads (more stable than PA6/PET).
Friction and Wear Resistance (Self-Lubricating Properties)
POM rods have a moderate surface hardness (Rockwell hardness M80-90), but possess an extremely low coefficient of friction and excellent self-lubrication:
Coefficient of friction: Approximately 0.15-0.3 when rubbing against steel (unlubricated), significantly lower than PA6 (approximately 0.3-0.4) and nylon (approximately 0.4-0.5);
Wear rate: In sliding friction, POM wear is only 1/3-1/2 that of PA6 (excellent wear resistance);
Self-lubricating property: POM rods operate smoothly under low-speed and medium-load conditions (e.g., linear guide sliders and gear meshes) without the need for additional lubrication.
Special Advantage: POM rods maintain low friction even in oil-free environments (suitable for applications such as food processing machinery and medical equipment where grease contamination is prohibited). For further improved wear resistance, graphite/molybdenum disulfide-filled reinforced POM rods can be selected.
Thermal Properties
Melting Point: Homopolymer approximately 175°C, Copolymer approximately 165°C (processing temperature must be slightly above the melting point);
Heat Deflection Temperature (HDT): Unreinforced approximately 110-125°C (under 0.45 MPa load), short-term withstand temperature of 140-150°C; the HDT of copolymer is typically 5-10°C higher than that of homopolymer.
Long-term Operating Temperature: ≤80-100°C (continuous use), short-term withstand temperature of 120-130°C (e.g., in hot assembly applications).
Note: POM is not heat-resistant (it will soften and deform above 100°C). For high-temperature environments, use glass fiber-reinforced POM (which can increase the HDT to over 150°C) or switch to a high-temperature-resistant engineering plastic (such as PEEK).
Chemical Properties
Chemical Corrosion Resistance: Stable to weak acids (e.g., dilute acetic acid, carbonic acid), weak bases (e.g., soapy water), and saline solutions (e.g., sodium chloride); resistant to most non-oxidizing organic solvents (e.g., ethanol, gasoline, and lubricating oils); however, susceptible to strong acids (e.g., concentrated sulfuric acid/nitric acid), strong bases (e.g., concentrated sodium hydroxide), ketones (e.g., acetone), and halogenated hydrocarbons (e.g., chloroform).
Oil Resistance: Excellent resistance to mineral oil, gear oil, and hydraulic oil (volume change rate <3%), making it suitable for lubricated environments (e.g., transmission components within gearboxes).
Special Applications: POM rods are virtually unaffected by humid environments (extremely low water absorption), but prolonged exposure to strong oxidizing chemicals (e.g., bleach) can cause material degradation.
Electrical Properties
Insulation: Volume resistivity >10¹⁴ Ω·cm, dielectric strength 18-25 kV/mm, making it an excellent insulating material (suitable for electronic device supports).
Dielectric constant: 3.0-3.5 (low and stable), suitable for insulation protection of low-frequency electronic components.
Processability and Environmental Performance
Processability: Can be processed by cutting (CNC/tool), drilling, tapping, turning (similar to metalworking), and polishing. Suitable for precision lathes (surface roughness Ra ≤ 0.8 μm) and CNC milling (accuracy ±0.05 mm).
Recyclability: POM is a recyclable plastic (recycling code "7"), produces no toxic gases when burned (superior to PVC), and complies with environmental regulations (such as RoHS and REACH).
Surface Treatment: Secondary processing is possible through spraying (such as antistatic coating), electroplating (such as nickel/chromium coating for improved wear resistance and decorative effects), and flame treatment (to enhance ink adhesion).
