Aluminum 3003-O vs. Plastic TPU

Compare Aluminum 3003-O vs. Plastic TPU strength, stiffness, weight and thermal properties.

Mechanical	Aluminum 3003-O	Plastic TPU
Yield strength	40MPa1	not given (tensile used)
Ultimate tensile strength	110MPa1	23.7MPa2
Flexural strength	not sourced	4.1MPa2
Elongation at break	30%1	not sourced
Young's modulus (stiffness)	69GPa11,030x stiffer	0.067GPa2
Density	2,730kg/m³1	1,220kg/m³22.24x lighter
Strength to weight	14.7kN·m/kg	19.4kN·m/kg33% higher
Stiffness to weight	25.3MN·m/kg460x higher	0.0549MN·m/kg
Poisson's ratio	not sourced	not sourced
Shear modulus	not sourced	not sourced
Bulk modulus	not sourced	not sourced
Speed of sound	5,027m/s21.5x faster	234m/s

Stiffness against densityHigher and further left: stiffer for its weight

Strength against densityHigher and further left: stronger for its weight

Thermal	Aluminum 3003-O	Plastic TPU
Thermal conductivity	193W/m·K1	not sourced
Thermal expansion	23.2µm/m·K1	not sourced
100 mm part over a 50 °C swing	116µm growth	not sourced
Specific heat	not sourced	not sourced
Heats up and cools (diffusivity)	not sourced	not sourced
Thermal shock resistance	not sourced	not sourced
Melting point	melting range640–655°C1	217°C2
Max service temperature	not sourced	HDT 0.455 MPa50.3°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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Sources2 documents: Kaiser Aluminum, UltiMaker

Aluminum 3003-O: 3003-O (annealed) aluminium-manganese alloy, the heat-exchanger tube and brazing alloy, Kaiser Aluminum Tube & Pipe Alloy 3003 Technical Data (Rev. 05/06), typical properties; specific heat from the NIST cryogenic 3003-F fit at 293 K.
Plastic TPU: Ultimaker TPU 95A, 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 (file v5.00), April 29, 2022.

1
Alloy 3003 Tube & Pipe Technical Data, Rev. 05/06Kaiser Aluminumarchived copyAluminum 3003-O · Yield strength: typical, O, 0.0625 in specimenAluminum 3003-O · Ultimate tensile strength: typical, OAluminum 3003-O · Elongation at break: typical, O, in 4DAluminum 3003-O · Young's modulus (stiffness): typicalAluminum 3003-O · Density: nominal, 20 °CAluminum 3003-O · Thermal conductivity: typical, O, 20 °CAluminum 3003-O · Thermal expansion: typical, mean 20-100 °CAluminum 3003-O · Melting point: melting range
2
Ultimaker TPU 95A Technical Data Sheet, v5.00UltiMakerarchived copyPlastic TPU · Ultimate tensile strength: typical, stress at breakPlastic TPU · Flexural strength: typicalPlastic TPU · Young's modulus (stiffness): typicalPlastic TPU · Density: typicalPlastic TPU · Melting point: typicalPlastic TPU · Max service temperature: HDT 0.455 MPa (printed specimens)

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

Questions

Mechanical

Is Aluminum 3003-O stronger than Plastic TPU?

Aluminum 3003-O is stronger: its yield strength is 40 MPa against tensile strength 23.7 MPa for Plastic TPU (1.69x).

Which is lighter, Aluminum 3003-O or Plastic TPU?

Plastic TPU is lighter: 1,220 kg/m³ against 2,730 kg/m³ for Aluminum 3003-O.

Which is stiffer, Aluminum 3003-O or Plastic TPU?

Aluminum 3003-O is stiffer: Young's modulus 69 GPa against 0.067 GPa for Plastic TPU, so the same part in Aluminum 3003-O deflects less under the same load.

Which is lighter for the same job, Aluminum 3003-O or Plastic TPU?

For the same stiffness or strength: Aluminum 3003-O is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate; Plastic TPU is lighter for a strong rod or tie, strong beam, strong panel or plate.

Part that must be	Aluminum 3003-O	Plastic TPU
Stiff rod or tie (tension)	lighter	460x heavier
Stiff beam (bending)	lighter	14.3x heavier
Stiff panel or plate	lighter	4.51x heavier
Strong rod or tie	33% heavier	lighter
Strong beam	1.58x heavier	lighter
Strong panel or plate	1.72x 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).