Materials / Compare
Plastic HDPE vs. DMLS 316L Stainless Steel
Compare Plastic HDPE vs. DMLS 316L Stainless Steel strength, stiffness, weight and thermal properties.
| Try it on a partA bracket to run stress or thermal on, free in your browser | Open in LessCAD | Open in LessCAD |
|---|---|---|
| Mechanical | ||
| Yield strength | 24MPasourcetypical, tensile stress at yield 23 °C, 50 mm/min ISO 527 | 530MPasourcetypical, as manufactured, horizontal |
| Ultimate tensile strength | not sourced | 640MPasourcetypical, as manufactured, horizontal |
| Elongation at break | not sourced | 40%sourcetypical at break, as manufactured, horizontal |
| Young's modulus (stiffness) | 0.9GPasourcetypical, tensile modulus 23 °C ISO 527 | 185GPasourcetypical, as built, horizontal (XY); EOSINT M280-400W / M290-400W, 316L_Surface 1.0, 20 µm (2014 sheet) |
| Density | 950kg/m³sourcetypical, ISO 1183 | 7,900kg/m³sourcepart density (ISO 3369, not labelled min or typical), EOS M 290, 40 µm FlexLine |
| Strength to weight | 25.3kN·m/kg | 67.1kN·m/kg2.66x higher |
| Stiffness to weight | 0.947MN·m/kg | 23.4MN·m/kg24.7x higher |
| Poisson's ratio | 0.4–0.45sourcebase material: high-density polyethylene family (INEOS Olefins & Polymers USA, Typical Engineering Properties of HDPE) | 0.3sourcebase material: austenitic stainless steels incl. 1.4404 (316L), design value |
| Shear modulus | 0.316GPa | 71.2GPa225x stiffer in shear |
| Bulk modulus | 2GPa | 154GPa |
| Speed of sound | 973m/s | 4,839m/s |
| Thermal | ||
| Thermal conductivity | 0.4–0.49W/m·Ksourcebase material: high-density polyethylene family (INEOS Olefins & Polymers USA, Typical Engineering Properties of HDPE) | 16.2W/m·Ksourcebase material: wrought 316/316L (Cleveland-Cliffs), at 100 °C |
| Thermal expansion | 120µm/m·Ksourcebase material: high-density polyethylene family (INEOS Olefins & Polymers USA, Typical Engineering Properties of HDPE) | 15.7µm/m·Ksourcemean 25-100 °C, ASTM E228 |
| 100 mm part over a 50 °C swing | 600µm growth | 78.6µm growth7.63x less |
| Specific heat | 2,250J/kg·Ksourcebase material: high-density polyethylene family (INEOS Olefins & Polymers USA, Typical Engineering Properties of HDPE) | 500J/kg·Ksourcebase material: wrought 316/316L (Cleveland-Cliffs), 0-100 °C |
| Heats up and cools (diffusivity) | 0.208mm²/s | 4.1mm²/s19.7x faster |
| Thermal shock resistance | 56.9W/m | 2,067W/m36.3x more resistant |
| Values for | LyondellBasell Hostalen 23050 B high density polyethylene, typical ISO values | EOS StainlessSteel 316L (powder 9011-0032), EOS M 290, ParameterSet 316L 20µm Surface M290/400W, as manufactured, horizontal; ISO 6892-1 |
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.
DMLS 316L Stainless Steel is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is Plastic HDPE stronger than DMLS 316L Stainless Steel?
DMLS 316L Stainless Steel is stronger: its yield strength is 530 MPa against 24 MPa for Plastic HDPE (22.1x).
Which is lighter, Plastic HDPE or DMLS 316L Stainless Steel?
Plastic HDPE is lighter: 950 kg/m³ against 7,900 kg/m³ for DMLS 316L Stainless Steel.
Which is stiffer, Plastic HDPE or DMLS 316L Stainless Steel?
DMLS 316L Stainless Steel is stiffer: Young's modulus 185 GPa against 0.9 GPa for Plastic HDPE, so the same part in DMLS 316L Stainless Steel deflects less under the same load.
Which is lighter for the same job, Plastic HDPE or DMLS 316L Stainless Steel?
For the same stiffness or strength: Plastic HDPE is lighter for a stiff panel or plate, strong beam, strong panel or plate; DMLS 316L Stainless Steel is lighter for a stiff rod or tie (tension), stiff beam (bending), strong rod or tie.
| Part that must be | Plastic HDPE | DMLS 316L Stainless Steel |
|---|---|---|
| Stiff rod or tie (tension) | 24.7x heavier | lighter |
| Stiff beam (bending) | 1.72x heavier | lighter |
| Stiff panel or plate | lighter | 41% heavier |
| Strong rod or tie | 2.66x heavier | lighter |
| Strong beam | lighter | 6% heavier |
| Strong panel or plate | lighter | 1.77x 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 conducts heat better, Plastic HDPE or DMLS 316L Stainless Steel?
DMLS 316L Stainless Steel conducts heat better: 16.2 W/m·K against 0.445 W/m·K for Plastic HDPE.
Which expands less with temperature?
DMLS 316L Stainless Steel expands less: 15.7 µm/m·K against 120 µm/m·K for Plastic HDPE.