Plastic ABS (bulk/injection) vs. Plastic PETG

Compare Plastic ABS (bulk/injection) vs. Plastic PETG strength, stiffness, weight and thermal properties.

Plastic ABS (bulk/injection)Bulk polymer (molded or machined)

Mechanical	Plastic ABS (bulk/injection)	Plastic PETG
Yield strength	45MPa1	46.2MPa2
Ultimate tensile strength	not stated (yield given)	46.2MPa2
Flexural strength	65MPa1	78.9MPa221% stronger in bending
Elongation at break	10%132% more ductile	7.6%2
Young's modulus (stiffness)	2.3GPa119% stiffer	1.94GPa2
Density	1,040kg/m³122% lighter	1,270kg/m³2
Strength to weight	43.3kN·m/kg19% higher	36.4kN·m/kg
Stiffness to weight	2.21MN·m/kg45% higher	1.53MN·m/kg
Poisson's ratio	0.393	not sourced
Shear modulus	0.827GPa	not sourced
Bulk modulus	3.48GPa	not sourced
Speed of sound	1,487m/s20% faster	1,236m/s

Stiffness against densityHigher and further left: stiffer for its weight

Strength against densityHigher and further left: stronger for its weight

Thermal	Plastic ABS (bulk/injection)	Plastic PETG
Thermal conductivity	0.17W/m·K1	base material0.21W/m·K424% more heat through a fin
Thermal expansion	range80–110µm/m·K1	base material51µm/m·K4
100 mm part over a 50 °C swing	475µm growth	255µm growth1.86x less
Specific heat	not sourced	base material1,300J/kg·K4
Heats up and cools (diffusivity)	not sourced	0.127mm²/s
Thermal shock resistance	21.4W/m	not sourced
Glass transition	not sourced	77.4°C2
Max service temperature	HDT 1.8 MPa94°C1	HDT 0.455 MPa76.2°C2

Thermal conductivity against densityHigher and further left: spreads more heat for its weight

Thermal expansion against thermal conductivityLower and further right: warps less when heated

Try it on a partA bracket to run stress or thermal on, free in your browser	Open in LessCAD	Open in LessCAD

Sources4 documents: INEOS Styrolution, UltiMaker, Covestro, Eastman

Plastic ABS (bulk/injection): INEOS Styrolution Terluran GP-22 general-purpose injection-molding ABS, ISO typical values (TDS revision 08/01/2022)
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.

1
Terluran GP-22 (ABS) Product Data SheetINEOS StyrolutionPlastic ABS (bulk/injection) · Yield strength: typical, tensile stress at yield 23 °CPlastic ABS (bulk/injection) · Flexural strength: typical, 23 °CPlastic ABS (bulk/injection) · Elongation at break: nominal strain at break, 23 °CPlastic ABS (bulk/injection) · Young's modulus (stiffness): typicalPlastic ABS (bulk/injection) · Density: typicalPlastic ABS (bulk/injection) · Thermal conductivity: typicalPlastic ABS (bulk/injection) · Thermal expansion: rangePlastic ABS (bulk/injection) · Max service temperature: HDT 1.8 MPa (annealed 4 h/80 °C)
2
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)
3
Engineering Polymers Part and Mold Design: Thermoplastics, A Design GuideCovestroarchived copyPlastic ABS (bulk/injection) · Poisson's ratio: typical, ABS family (Covestro Part and Mold Design guide, Table 3-1)
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 ABS (bulk/injection) stronger than Plastic PETG?

Plastic PETG is stronger: its yield strength is 46.2 MPa against 45 MPa for Plastic ABS (bulk/injection) (3%).

Which is lighter, Plastic ABS (bulk/injection) or Plastic PETG?

Plastic ABS (bulk/injection) is lighter: 1,040 kg/m³ against 1,270 kg/m³ for Plastic PETG.

Which is stiffer, Plastic ABS (bulk/injection) or Plastic PETG?

Plastic ABS (bulk/injection) is stiffer: Young's modulus 2.3 GPa against 1.94 GPa for Plastic PETG, so the same part in Plastic ABS (bulk/injection) deflects less under the same load.

Which is lighter for the same job, Plastic ABS (bulk/injection) or Plastic PETG?

For the same stiffness or strength: Plastic ABS (bulk/injection) 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 be	Plastic ABS (bulk/injection)	Plastic PETG
Stiff rod or tie (tension)	lighter	45% heavier
Stiff beam (bending)	lighter	33% heavier
Stiff panel or plate	lighter	29% heavier
Strong rod or tie	lighter	19% heavier
Strong beam	lighter	20% heavier
Strong panel or plate	lighter	21% heavier

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 ABS (bulk/injection) or Plastic PETG?

Plastic ABS (bulk/injection) stretches further before it breaks: 10% elongation at break against 7.6% for Plastic PETG.

Thermal

Which conducts heat better, Plastic ABS (bulk/injection) or Plastic PETG?

Plastic PETG conducts heat better: 0.21 W/m·K against 0.17 W/m·K for Plastic ABS (bulk/injection).

Which expands less with temperature?

Plastic PETG expands less: 51 µm/m·K against 95 µm/m·K for Plastic ABS (bulk/injection).