Materials / Compare

Plastic PETG vs. Plastic POM/Acetal

Compare Plastic PETG vs. Plastic POM/Acetal strength, stiffness, weight and thermal properties.

Plastic PETG3D printed (FDM)
Plastic POM/AcetalBulk polymer (molded or machined)
MechanicalPlastic PETGPlastic POM/Acetal
Yield strength46.2MPa169MPa249% stronger
Ultimate tensile strength46.2MPa169MPa249% stronger
Compressive strengthnot sourced124MPa2
Flexural strength78.9MPa199MPa2
Elongation at break7.6%175%29.87x more ductile
Young's modulus (stiffness)1.94GPa12.8GPa244% stiffer
Density1,270kg/m³112% lighter1,420kg/m³3
Strength to weight36.4kN·m/kg48.6kN·m/kg34% higher
Stiffness to weight1.53MN·m/kg1.97MN·m/kg29% higher
Poisson's rationot sourced0.352
Shear modulusnot sourced1.04GPa
Bulk modulusnot sourced3.11GPa
Speed of sound1,236m/s1,404m/s14% faster
1k10k0.1110100Density (kg/m³)Young's modulus (GPa)Plastic PLAPlastic ABSPlastic TPUPlastic NylonWoodAluminumSteelIronTitaniumSteel AISI 1018Stainless Steel 304Stainless Steel 316Aluminum 6061-T6Aluminum 7075-T6Brass C360Copper C110Copper C10100Copper C12200GlassSteel AISI 1045Steel AISI 4340Steel A992Stainless Steel 303Stainless Steel 17-4PHAluminum 2024-T351Aluminum 5052-H32Aluminum 7050-T7451Titanium Ti-6Al-4VBrass C260Nickel Inconel 718Magnesium AZ31B-H24Zinc Zamak 3Plastic ABS (bulk/injection)Plastic PolycarbonatePlastic Nylon PA6Plastic Nylon PA66Plastic PEEKPlastic UHMWPEPlastic HDPEPlastic PolypropylenePlastic PMMAFDM ASAFDM PolycarbonateFDM PAHT-CFFDM HIPSSLA Resin StandardSLA Resin Tough 2000SLS PA12 NylonDMLS AlSi10Mg AluminumDMLS Ti-6Al-4V ELI TitaniumDMLS 316L Stainless SteelDMLS 17-4PH Stainless SteelConcretePCB Laminate FR-4SiliconCeramic Alumina 96%Ceramic Aluminum NitrideAluminum A380Aluminum 6063-T6Aluminum 1100-OAluminum 3003-OAluminum ADC12Magnesium AZ91DSolder SAC305Plastic PBT GF30Plastic PPS GF40Plastic LCP GF30Plastic PETGPlastic POM/Acetal
Stiffness against densityHigher and further left: stiffer for its weight
1k10k101001kDensity (kg/m³)Yield strength (MPa)Plastic PLAPlastic ABSPlastic TPUPlastic NylonRubberWoodAluminumSteelIronTitaniumSteel AISI 1018Stainless Steel 304Stainless Steel 316Aluminum 6061-T6Aluminum 7075-T6Brass C360Copper C110Copper C10100Copper C12200GlassSteel AISI 1045Steel AISI 4340Steel A992Stainless Steel 303Stainless Steel 17-4PHAluminum 2024-T351Aluminum 5052-H32Aluminum 7050-T7451Titanium Ti-6Al-4VBrass C260Nickel Inconel 718Magnesium AZ31B-H24Zinc Zamak 3Plastic ABS (bulk/injection)Plastic PolycarbonatePlastic Nylon PA6Plastic Nylon PA66Plastic PEEKPlastic PTFEPlastic UHMWPEPlastic HDPEPlastic PolypropylenePlastic PMMAFDM ASAFDM PolycarbonateFDM PAHT-CFFDM HIPSSLA Resin StandardSLA Resin Tough 2000SLA Resin Elastic 50ASLS PA12 NylonDMLS AlSi10Mg AluminumDMLS Ti-6Al-4V ELI TitaniumDMLS 316L Stainless SteelDMLS 17-4PH Stainless SteelBrickPCB Laminate FR-4SiliconCeramic Alumina 96%Aluminum A380Aluminum 6063-T6Aluminum 1100-OAluminum 3003-OAluminum ADC12Magnesium AZ91DSolder SAC305Plastic PBT GF30Plastic PPS GF40Plastic LCP GF30Plastic PETGPlastic POM/Acetal
Strength against densityHigher and further left: stronger for its weight
ThermalPlastic PETGPlastic POM/Acetal
Thermal conductivitybase material0.21W/m·K40.4W/m·K21.9x more heat through a fin
Thermal expansionbase material51µm/m·K42.39x lessmean122µm/m·K2
100 mm part over a 50 °C swing255µm growth2.39x less610µm growth
Specific heatbase material1,300J/kg·K4average -18 to 100 °C1,465J/kg·K213% higher
Heats up and cools (diffusivity)0.127mm²/s0.192mm²/s1.51x faster
Thermal shock resistancenot sourced52.5W/m
Melting pointnot sourced175°C2
Glass transition77.4°C1not sourced
Max service temperatureHDT 0.455 MPa76.2°C1HDT 1.8 MPa125°C2
1k10k0.1110100Density (kg/m³)Thermal conductivity (W/m·K)Plastic PLAPlastic ABSPlastic NylonRubberWoodAluminumSteelIronTitaniumSteel AISI 1018Stainless Steel 304Stainless Steel 316Aluminum 6061-T6Aluminum 7075-T6Brass C360Copper C110Copper C10100Copper C12200GlassSteel AISI 1045Steel AISI 4340Steel A992Stainless Steel 303Stainless Steel 17-4PHAluminum 2024-T351Aluminum 5052-H32Aluminum 7050-T7451Titanium Ti-6Al-4VBrass C260Nickel Inconel 718Magnesium AZ31B-H24Zinc Zamak 3Plastic ABS (bulk/injection)Plastic PolycarbonatePlastic Nylon PA6Plastic Nylon PA66Plastic PEEKPlastic PTFEPlastic UHMWPEPlastic HDPEPlastic PolypropylenePlastic PMMAFDM ASAFDM PolycarbonateFDM HIPSSLA Resin StandardDMLS AlSi10Mg AluminumDMLS Ti-6Al-4V ELI TitaniumDMLS 316L Stainless SteelDMLS 17-4PH Stainless SteelConcreteBrickPCB Laminate FR-4SiliconCeramic Alumina 96%Ceramic Aluminum NitrideAluminum A380Aluminum 6063-T6Aluminum 1100-OAluminum 3003-OAluminum ADC12Magnesium AZ91DSolder SAC305Plastic PBT GF30Plastic PPS GF40Plastic LCP GF30Plastic PETGPlastic POM/Acetal
Thermal conductivity against densityHigher and further left: spreads more heat for its weight
0.111010010100Thermal conductivity (W/m·K)Thermal expansion (µm/m·K)Plastic ABSPlastic NylonWoodAluminumSteelIronTitaniumSteel AISI 1018Stainless Steel 304Stainless Steel 316Aluminum 6061-T6Aluminum 7075-T6Brass C360Copper C110Copper C10100Copper C12200GlassSteel AISI 1045Steel AISI 4340Steel A992Stainless Steel 303Stainless Steel 17-4PHAluminum 2024-T351Aluminum 5052-H32Aluminum 7050-T7451Titanium Ti-6Al-4VBrass C260Nickel Inconel 718Magnesium AZ31B-H24Zinc Zamak 3Plastic ABS (bulk/injection)Plastic PolycarbonatePlastic Nylon PA6Plastic Nylon PA66Plastic PEEKPlastic PTFEPlastic UHMWPEPlastic HDPEPlastic PolypropylenePlastic PMMAFDM ASAFDM PolycarbonateFDM HIPSSLA Resin StandardDMLS AlSi10Mg AluminumDMLS Ti-6Al-4V ELI TitaniumDMLS 316L Stainless SteelDMLS 17-4PH Stainless SteelConcreteBrickPlywoodPCB Laminate FR-4SiliconCeramic Alumina 96%Ceramic Aluminum NitrideAluminum A380Aluminum 6063-T6Aluminum 1100-OAluminum 3003-OAluminum ADC12Magnesium AZ91DSolder SAC305Plastic PBT GF30Plastic PPS GF40Plastic LCP GF30Plastic PETGPlastic POM/Acetal
Thermal expansion against thermal conductivityLower and further right: warps less when heated
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Sources4 documents: UltiMaker, DuPont, Eastman
Plastic PETG
Ultimaker PETG, 3D-printed specimens, XY (flat); Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS v1.00, April 29, 2022.
Plastic POM/Acetal
DuPont Delrin 100 acetal homopolymer, Table 2 'Typical Properties of Delrin Acetal Resins' (ASTM methods), Delrin Design Guide Module III hosted on delrin.com
  1. 1
    Ultimaker PETG Technical Data Sheet, v1.00UltiMakerarchived copyPlastic PETG · Yield strength: typicalPlastic PETG · Ultimate tensile strength: typical, peak stress (= stress at yield)Plastic PETG · Flexural strength: typicalPlastic PETG · Elongation at break: typicalPlastic PETG · Young's modulus (stiffness): typicalPlastic PETG · Density: typicalPlastic PETG · Glass transition: typicalPlastic PETG · Max service temperature: HDT 0.455 MPa (printed specimens)
  2. 2
    Delrin Acetal Resin Design Guide, Module IIIDuPontarchived copyPlastic POM/Acetal · Yield strength: typical (single ASTM D638 tensile strength)Plastic POM/Acetal · Ultimate tensile strength: typicalPlastic POM/Acetal · Compressive strength: compressive stress at 10% deformationPlastic POM/Acetal · Flexural strength: flexural yield strength, typicalPlastic POM/Acetal · Elongation at break: typicalPlastic POM/Acetal · Young's modulus (stiffness): typicalPlastic POM/Acetal · Poisson's ratio: typicalPlastic POM/Acetal · Thermal conductivity: typicalPlastic POM/Acetal · Thermal expansion: mean, 29 to 60 °CPlastic POM/Acetal · Specific heat: average -18 to 100 °C, Delrin acetal resins (not grade-specific)Plastic POM/Acetal · Melting point: crystalline melting pointPlastic POM/Acetal · Max service temperature: HDT 1.8 MPa (annealed)
  3. 3
    Delrin 100 Product Data SheetDuPontPlastic POM/Acetal · Density: typical (DuPont product information for Delrin 100 NC010; 'The data listed here fall within the normal range of product properties')
  4. 4
    Eastar Copolyester 6763 Product Data SheetEastmanPlastic PETG · Thermal conductivity: base material: Eastman Eastar Copolyester 6763 (PETG), typicalPlastic PETG · Thermal expansion: base material: Eastman Eastar Copolyester 6763 (PETG), typicalPlastic PETG · Specific heat: base material: Eastman Eastar Copolyester 6763 (PETG), DSC at 60 °C (lowest temperature listed)

Each number points to the document that states it, with the exact basis. Values without a number are computed from the sourced ones. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.

Plastic PETG is 3D printed: its properties depend on build direction and print settings; these are typical values.

Questions

Mechanical

Is Plastic PETG stronger than Plastic POM/Acetal?

Plastic POM/Acetal is stronger: its yield strength is 69 MPa against 46.2 MPa for Plastic PETG (49%).

Which is lighter, Plastic PETG or Plastic POM/Acetal?

Plastic PETG is lighter: 1,270 kg/m³ against 1,420 kg/m³ for Plastic POM/Acetal.

Which is stiffer, Plastic PETG or Plastic POM/Acetal?

Plastic POM/Acetal is stiffer: Young's modulus 2.8 GPa against 1.94 GPa for Plastic PETG, so the same part in Plastic POM/Acetal deflects less under the same load.

Which is lighter for the same job, Plastic PETG or Plastic POM/Acetal?

For the same stiffness or strength: Plastic POM/Acetal is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.

Part that must bePlastic PETGPlastic POM/Acetal
Stiff rod or tie (tension)29% heavierlighter
Stiff beam (bending)7% heavierlighter
Stiff panel or plate1% heavierlighter
Strong rod or tie34% heavierlighter
Strong beam17% heavierlighter
Strong panel or plate9% heavierlighter

For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).

Which is more ductile, Plastic PETG or Plastic POM/Acetal?

Plastic POM/Acetal stretches further before it breaks: 75% elongation at break against 7.6% for Plastic PETG.

Thermal

Which conducts heat better, Plastic PETG or Plastic POM/Acetal?

Plastic POM/Acetal conducts heat better: 0.4 W/m·K against 0.21 W/m·K for Plastic PETG.

Which expands less with temperature?

Plastic PETG expands less: 51 µm/m·K against 122 µm/m·K for Plastic POM/Acetal.

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