Plastic PETG vs. SLS PA12 Nylon

Compare Plastic PETG vs. SLS PA12 Nylon strength, stiffness, weight and thermal properties.

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Mechanical
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Yield strength	46.2MPasourcetypical	not given (tensile used)
Ultimate tensile strength	46.2MPasourcetypical, peak stress (= stress at yield)	48MPasourcetypical
Flexural strength	78.9MPasourcetypical	not sourced
Elongation at break	7.6%sourcetypical	18%sourcetypical2.37x more ductile
Young's modulus (stiffness)	1.94GPasourcetypical18% stiffer	1.65GPasourcetypical
Density	1,270kg/m³sourcetypical	930kg/m³sourcetypical37% lighter
Strength to weight	36.4kN·m/kg	51.6kN·m/kg42% higher
Stiffness to weight	1.53MN·m/kg	1.77MN·m/kg16% higher
Poisson's ratio	not sourced	not sourced
Shear modulus	not sourced	not sourced
Bulk modulus	not sourced	not sourced
Speed of sound	1,236m/s	1,332m/s
Thermal
Thermal conductivity	0.21W/m·Ksourcebase material: Eastman Eastar Copolyester 6763 (PETG), typical	not sourced
Thermal expansion	51µm/m·Ksourcebase material: Eastman Eastar Copolyester 6763 (PETG), typical	not sourced
100 mm part over a 50 °C swing	255µm growth	not sourced
Specific heat	1,300J/kg·Ksourcebase material: Eastman Eastar Copolyester 6763 (PETG), DSC at 60 °C (lowest temperature listed)	not sourced
Heats up and cools (diffusivity)	0.127mm²/s	not sourced
Thermal shock resistance	not sourced	not sourced
Melting point	not sourced	176°Csourcetypical
Glass transition	77.4°Csourcetypical	not sourced
Max service temperature	76.2°CsourceHDT 0.455 MPa (printed specimens)	64°CsourceHDT 1.8 MPa, X orientation
Values for	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.	EOS PA 2200 (PA12) Material Data Sheet, process parameter 'Balance' at 120 µm layer thickness, X orientation, dry (conditioned values not given). Live MDS status 04.10.2026, last changed 10.09.2026; PDF via ?topdf=... link on the same page.

Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.

Plastic PETG and SLS PA12 Nylon are 3D printed: their properties depend on build direction and print settings; these are typical values.

Questions

Is Plastic PETG stronger than SLS PA12 Nylon?

SLS PA12 Nylon is stronger: its tensile strength is 48 MPa against yield strength 46.2 MPa for Plastic PETG (4%).

Which is lighter, Plastic PETG or SLS PA12 Nylon?

SLS PA12 Nylon is lighter: 930 kg/m³ against 1,270 kg/m³ for Plastic PETG.

Which is stiffer, Plastic PETG or SLS PA12 Nylon?

Plastic PETG is stiffer: Young's modulus 1.94 GPa against 1.65 GPa for SLS PA12 Nylon, so the same part in Plastic PETG deflects less under the same load.

Which is lighter for the same job, Plastic PETG or SLS PA12 Nylon?

For the same stiffness or strength: SLS PA12 Nylon 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 PETG	SLS PA12 Nylon
Stiff rod or tie (tension)	16% heavier	lighter
Stiff beam (bending)	26% heavier	lighter
Stiff panel or plate	29% heavier	lighter
Strong rod or tie	42% heavier	lighter
Strong beam	40% heavier	lighter
Strong panel or plate	39% heavier	lighter

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 SLS PA12 Nylon?

SLS PA12 Nylon stretches further before it breaks: 18% elongation at break against 7.6% for Plastic PETG.

Among 59 materials

Stiffness against density

Strength against density