FDM ASA vs. Rubber

Compare FDM ASA vs. Rubber strength, stiffness, weight and thermal properties.

FDM ASA3D printed (FDM)

RubberBulk polymer (molded or machined)

Mechanical	FDM ASA	Rubber
Yield strength	not given (tensile used)	not given (tensile used)
Ultimate tensile strength	37MPa11.61x stronger	23MPa2
Flexural strength	65MPa1	not sourced
Elongation at break	9.2%1	830%290.2x more ductile
Young's modulus (stiffness)	2.45GPa1	not sourced
Density	1,050kg/m³1	960kg/m³2
Strength to weight	35.2kN·m/kg47% higher	24kN·m/kg
Stiffness to weight	2.33MN·m/kg	not sourced
Poisson's ratio	not sourced	government0.53
Shear modulus	not sourced	not sourced
Bulk modulus	not sourced	not sourced
Speed of sound	1,528m/s	not sourced

Stiffness against densityHigher and further left: stiffer for its weight

Strength against densityHigher and further left: stronger for its weight

Thermal	FDM ASA	Rubber
Thermal conductivity	base material0.17W/m·K413% more heat through a fin	0.151W/m·K5
Thermal expansion	base material80–110µm/m·K4	not sourced
100 mm part over a 50 °C swing	475µm growth	not sourced
Specific heat	not sourced	government1,881J/kg·K3
Heats up and cools (diffusivity)	not sourced	0.0836mm²/s
Thermal shock resistance	not sourced	not sourced
Max service temperature	HDT 1.8 MPa92°C1	70°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

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Sources5 documents: Bambu Lab, Weir Minerals, National Institute of Standards and Technology, INEOS Styrolution, Defense Technical Information Center

FDM ASA: Bambu Lab ASA, TDS V3.0, printed specimens X-Y; nozzle 260 °C, bed 80 °C, 200 mm/s, 100% infill; annealed and dried 80 °C for 12 h before testing.
Rubber: Weir Minerals Linatex Premium rubber (95 % natural rubber), typical physical properties, spec sheet WMD0118/202305

1
Bambu ASA Technical Data Sheet, V3.0Bambu LabFDM ASA · Ultimate tensile strength: typicalFDM ASA · Flexural strength: typicalFDM ASA · Elongation at break: typicalFDM ASA · Young's modulus (stiffness): typicalFDM ASA · Density: typicalFDM ASA · Max service temperature: HDT 1.8 MPa
2
Linatex Premium Rubber Spec Sheet (WMD0118, 2023)Weir MineralsRubber · Ultimate tensile strength: typicalRubber · Elongation at break: typicalRubber · Density: typical (specific gravity)Rubber · Max service temperature: continuous use operating range
3
Compressibility of Natural Rubber at Pressures Below 500 kg/cm², J. Res. NBS 68A (1964)National Institute of Standards and Technologyarchived copyRubber · Poisson's ratio: government (NBS J. Res. 68A, 1964): computed by NBS for peroxide-cured gum NR vulcanizate, 25 °C, infinitesimal deformation (0.49 in the solver: the linear element locks as the ratio nears 0.5 (nearly incompressible).)Rubber · Specific heat: government (NBS J. Res. 68A, Table 7; values observed for unvulcanized NR by Bekkedahl and Matheson), 25 °C
4
Luran S 777K (ASA) Product Data SheetINEOS StyrolutionFDM ASA · Thermal conductivity: base material: INEOS Styrolution Luran S 777K injection-molding ASA, typicalFDM ASA · Thermal expansion: base material: INEOS Styrolution Luran S 777K injection-molding ASA, range
5
Thermal Conductivity of Soft Vulcanized Natural Rubber: Selected Values (AD 643325)Defense Technical Information Centerarchived copyRubber · Thermal conductivity: government selected value (US Army Natick Laboratories TR 66-49-PR, 1966), soft vulcanized natural rubber, 25 °C

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.

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

Questions

Mechanical

Is FDM ASA stronger than Rubber?

FDM ASA is stronger: its tensile strength is 37 MPa against 23 MPa for Rubber (1.61x).

Which is lighter, FDM ASA or Rubber?

Rubber is lighter: 960 kg/m³ against 1,050 kg/m³ for FDM ASA.

Which is lighter for the same job, FDM ASA or Rubber?

For the same stiffness or strength: FDM ASA is lighter for a strong rod or tie, strong beam, strong panel or plate.

Part that must be	FDM ASA	Rubber
Strong rod or tie	lighter	47% heavier
Strong beam	lighter	26% heavier
Strong panel or plate	lighter	16% 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, FDM ASA or Rubber?

Rubber stretches further before it breaks: 830% elongation at break against 9.2% for FDM ASA.

Thermal

Which conducts heat better, FDM ASA or Rubber?

FDM ASA conducts heat better: 0.17 W/m·K against 0.151 W/m·K for Rubber.