The tables below demonstrate the values of static friction between two materials in a lubricated and non-lubricated situation. If motion is added between the materials, this will greatly affect the friction values. The values below are intended to be generic specifications. Valves may vary depending on the material's composition and surface finish, therefore for accurate values, tests should be conducted to determine accurate values.
| MATERIALS | COEFFICIENT OF FRICTION | |
|---|---|---|
| CLEAN | LUBRICATED | |
| Steel | 0.80 | 0.16 |
| Copper-lead alloy | 0.22 | -- |
| Phospher-bronze | 0.35 | -- |
| Aluminum-bronze | 0.45 | -- |
| Brass | 0.35 | 0.19 |
| Cast iron | 0.40 | 0.21 |
| Bronze | -- | 0.16 |
| Sintered bronze | -- | 0.13 |
| Hard carbon | 0.14 | 0.11 to 0.14 |
| Graphite | 0.10 | 0.10 |
| Tungsten carbide | 0.40 to 0.60 | 0.10 to 0.20 |
| Plexiglas | 0.40 to 0.50 | 0.40 to 0.50 |
| Polystyrene | 0.30 to 0.35 | 0.30 to 0.35 |
| Polythene | 0.20 | 0.20 |
| Teflon | 0.04 | 0.04 |
| MATERIAL COMBINATION | COEFFICIENT OF FRICTION | |
|---|---|---|
| CLEAN | LUBRICATED | |
| Aluminum & aluminum | 1.35 | 0.30 |
| Cadmium & cadmium | 0.50 | 0.05 |
| Chromium-chromium | 0.41 | 0.34 |
| Copper & copper | 1.00 | 0.08 |
| Iron & iron | 1.00 | 0.15 - 0.20 |
| Magnesium & magnesium | 0.60 | 0.08 |
| Nickel & nickel | 0.70 | 0.28 |
| Platinum & platinum | 1.20 | 0.25 |
| Silver & silver | 1.40 | 0.55 |
| Zinc & zinc | 0.60 | 0.04 |
| Glass & glass | 0.90 to 1.00 | 0.10 to 0.60 |
| Glass & metal | 0.50 to 0.70 | 0.20 to 0.30 |
| Diamond & diamond | 0.10 | 0.05 to 0.10 |
| Diamond & metal | 0.10 to 0.15 | 0.10 |
| Sapphire & sapphire | 0.20 | 0.20 |
| Hard carbon & carbon | 0.16 | 0.12 to 0.14 |
| Graphite & graphite (vacuum) | 0.50 to 0.80 | -- |
| Graphite-graphite | 0.10 | 0.10 |
| Tungsten carbide & tungsten carbide | 0.20 to 0.25 | 0.12 |
| Plexiglas & Plexiglas | 0.80 | 0.80 |
| Polystyrene & polystyrene | 0.50 | 0.50 |
| Teflon & Teflon | 0.04 | 0.04 |
| Nylon & nylon | 0.15 - 0.25 | -- |
| Solids & rubber | 1.00 to 4.00 | -- |
| Wood & wood (clean) | 0.25 to 0.50 | -- |
| Wood & wood (wet) | 0.20 | -- |
| Wood & metals (clean) | 0.20 to 0.60 | -- |
| Wood & metals (wet) | 0.20 | -- |
| Brick & wood | 0.60 | -- |
| Leather & wood | 0.30 to 0.40 | -- |
| Leather & metal (clean) | 0.60 | -- |
| Leather & metal (wet) | 0.40 | -- |
| Leather & metal (greasy) | 0.20 | -- |
| Brake material & cast iron | 0.4 | -- |
| Brake material on cast iron (wet) | 0.20 | -- |