Materials / Compare
Plastic Nylon PA66 vs. Stainless 316
Compare Plastic Nylon PA66 vs. Stainless 316 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 | 85MPasourcetypical, dry | 265MPasourcetypical (representative), annealed 1.0 mm sheet |
| Ultimate tensile strength | not sourced | 583MPasourcetypical (representative), annealed 1.0 mm sheet |
| Elongation at break | 30%sourcenominal strain at break, dry | 61%sourcetypical (representative), annealed, in 2 in. (51 mm) |
| Young's modulus (stiffness) | 3GPasourcetypical, dry | 200GPasourcetypical, in tension |
| Density | 1,130kg/m³sourcetypical7.1x lighter | 8,027kg/m³sourcetypical |
| Strength to weight | 75.2kN·m/kg2.28x higher | 33kN·m/kg |
| Stiffness to weight | 2.65MN·m/kg | 24.9MN·m/kg9.38x higher |
| Poisson's ratio | 0.4sourcebase material: unfilled polyamide (PA), conditioned, maker design-guide family value (Covestro Table 3-1) | 0.3sourcedesign value (structural stainless steels) |
| Shear modulus | 1.07GPa | 76.9GPa71.8x stiffer in shear |
| Bulk modulus | 5GPa | 167GPa |
| Speed of sound | 1,629m/s | 4,992m/s |
| Thermal | ||
| Thermal conductivity | 0.33W/m·Ksourcetypical | 14.6W/m·Ksource20–100 °C |
| Thermal expansion | 98µm/m·Ksourcelongitudinal, 23-55 °C | 16.5µm/m·Ksourcemean, 20–100 °C |
| 100 mm part over a 50 °C swing | 490µm growth | 82.5µm growth5.94x less |
| Specific heat | 1,700J/kg·Ksourcetypical | 450J/kg·Ksourceat 20 °C |
| Heats up and cools (diffusivity) | 0.172mm²/s | 4.04mm²/s23.5x faster |
| Thermal shock resistance | 57.2W/m | 821W/m14.3x more resistant |
| Melting point | 260°CsourceDSC | 1,390–1,440°Csourcemelting range |
| Max service temperature | 101°CsourceIEC 60216 temperature index, 20000 h | 871–899°Csourceoxidation (scaling) limit in air |
| Values for | BASF Ultramid A3K (PA66, unreinforced injection-moulding grade), Product Information 02/2026, dry values (ISO methods) | ATI 316 (UNS S31600), annealed 1.0 mm sheet, ATI technical data sheet (2012); Poisson's ratio from the Nickel Institute/SCI structural stainless design manual |
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.
Questions
Is Plastic Nylon PA66 stronger than Stainless 316?
Stainless 316 is stronger: its yield strength is 265 MPa against 85 MPa for Plastic Nylon PA66 (3.12x).
Which is lighter, Plastic Nylon PA66 or Stainless 316?
Plastic Nylon PA66 is lighter: 1,130 kg/m³ against 8,027 kg/m³ for Stainless 316.
Which is stiffer, Plastic Nylon PA66 or Stainless 316?
Stainless 316 is stiffer: Young's modulus 200 GPa against 3 GPa for Plastic Nylon PA66, so the same part in Stainless 316 deflects less under the same load.
Which is lighter for the same job, Plastic Nylon PA66 or Stainless 316?
For the same stiffness or strength: Plastic Nylon PA66 is lighter for a stiff panel or plate, strong rod or tie, strong beam, strong panel or plate; Stainless 316 is lighter for a stiff rod or tie (tension), stiff beam (bending).
| Part that must be | Plastic Nylon PA66 | Stainless 316 |
|---|---|---|
| Stiff rod or tie (tension) | 9.38x heavier | lighter |
| Stiff beam (bending) | 15% heavier | lighter |
| Stiff panel or plate | lighter | 1.75x heavier |
| Strong rod or tie | lighter | 2.28x heavier |
| Strong beam | lighter | 3.33x heavier |
| Strong panel or plate | lighter | 4.02x 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 Nylon PA66 or Stainless 316?
Stainless 316 conducts heat better: 14.6 W/m·K against 0.33 W/m·K for Plastic Nylon PA66.
Which expands less with temperature?
Stainless 316 expands less: 16.5 µm/m·K against 98 µm/m·K for Plastic Nylon PA66.