Appendix A
Friction Coefficients for some Common Materials and Materials Combinations
Materials and Material Combinations
|
Surface Conditions, Lubricant
|
Frictional Coefficient
|
||
---|---|---|---|---|
Static
– μstatic – |
Kinetic (sliding)
– μsliding – |
|||
Aluminum | Aluminum | Clean and Dry | 1.05 – 1.35 | 0.4 |
Aluminum | Aluminum | Lubricated and Greasy | 0.3 | |
Aluminum-bronze | Steel | Clean and Dry | 0.45 | |
Aluminum | Mild Steel | Clean and Dry | 0.61 | 0.47 |
Aluminum | Snow | Wet 0 oC | 0.4 | |
Aluminum | Snow | Dry 0 oC | 0.35 | |
Brake material2) | Cast iron | Clean and Dry | 0.4 | |
Brake material2) | Cast iron (wet) | Clean and Dry | 0.2 | |
Brass | Steel | Clean and Dry | 0.51 | 0.44 |
Brass | Steel | Grease | 0.19 | |
Brass | Steel | Castor oil | 0.11 | |
Brass | Cast Iron | Clean and Dry | 0.3 | |
Brass | Ice | Clean 0 oC | 0.02 | |
Brass | Ice | Clean -80 oC | 0.15 | |
Brick | Wood | Clean and Dry | 0.6 | |
Bronze | Steel | Grease | 0.16 | |
Bronze | Cast Iron | Clean and Dry | 0.22 | |
Bronze – sintered | Steel | Grease | 0.13 | |
Cadmium | Cadmium | Clean and Dry | 0.5 | |
Cadmium | Cadmium | Grease | 0.05 | |
Cadmium | Chromium | Clean and Dry | 0.41 | |
Cadmium | Chromium | Grease | 0.34 | |
Cadmium | Mild Steel | Clean and Dry | 0.46 | |
Cast Iron | Cast Iron | Clean and Dry | 1.1 | 0.15 |
Cast Iron | Cast Iron | Clean and Dry | 0.15 | |
Cast Iron | Cast Iron | Grease | 0.07 | |
Cast Iron | Oak | Clean and Dry | 0.49 | |
Cast Iron | Oak | Grease | 0.075 | |
Cast iron | Steel | Clean and Dry | 0.4 | |
Cast iron | Steel | Clean and Dry | 0.23 | |
Cast iron | Steel | Grease | 0.21 | 0.133 |
Car tire | Asphalt | Clean and Dry | 0.72 | |
Car tire | Grass | Clean and Dry | 0.35 | |
Carbon (hard) | Carbon | Clean and Dry | 0.16 | |
Carbon (hard) | Carbon | Grease | 0.12 – 0.14 | |
Carbon | Steel | Clean and Dry | 0.14 | |
Carbon | Steel | Grease | 0.11 – 0.14 | |
Chromium | Chromium | Clean and Dry | 0.41 | |
Chromium | Chromium | Grease | 0.34 | |
Copper-Lead alloy | Steel | Clean and Dry | 0.22 | |
Copper | Copper | Clean and Dry | 1.6 | |
Copper | Copper | Grease | 0.08 | |
Copper | Cast Iron | Clean and Dry | 1.05 | 0.29 |
Copper | Steel | Clean and Dry | 0.53 | 0.36 |
Copper | Steel | Grease | 0.18 | |
Copper | Steel | Oleic acid | 0.18 | |
Copper | Glass | Clean and Dry | 0.68 | 0.53 |
Cotton | Cotton | Threads | 0.3 | |
Diamond | Diamond | Clean and Dry | 0.1 | |
Diamond | Diamond | Grease | 0.05 – 0.1 | |
Diamond | Metals | Clean and Dry | 0.1 – 0.15 | |
Diamond | Metal | Grease | 0.1 | |
Garnet | Steel | Clean and Dry | 0.39 | |
Glass | Glass | Clean and Dry | 0.9 – 1.0 | 0.4 |
Glass | Glass | Grease | 0.1 – 0.6 | 0.09 – 0.12 |
Glass | Metal | Clean and Dry | 0.5 – 0.7 | |
Glass | Metal | Grease | 0.2 – 0.3 | |
Glass | Nickel | Clean and Dry | 0.78 | |
Glass | Nickel | Grease | 0.56 | |
Graphite | Steel | Clean and Dry | 0.1 | |
Graphite | Steel | Grease | 0.1 | |
Graphite | Graphite (in vacuum) | Clean and Dry | 0.5 – 0.8 | |
Graphite | Graphite | Clean and Dry | 0.1 | |
Graphite | Graphite | Grease | 0.1 | |
Hemp rope | Timber | Clean and Dry | 0.5 | |
Horseshoe | Rubber | Clean and Dry | 0.68 | |
Horseshoe | Concrete | Clean and Dry | 0.58 | |
Ice | Ice | Clean 0 oC | 0.1 | 0.02 |
Ice | Ice | Clean -12 oC | 0.3 | 0.035 |
Ice | Ice | Clean -80 oC | 0.5 | 0.09 |
Ice | Wood | Clean and Dry | 0.05 | |
Ice | Steel | Clean and Dry | 0.03 | |
Iron | Iron | Clean and Dry | 1.0 | |
Iron | Iron | Grease | 0.15 – 0.20 | |
Lead | Cast Iron | Clean and Dry | 0.43 | |
Leather | Oak | Parallel to grain | 0.61 | 0.52 |
Leather | Metal | Clean and Dry | 0.4 | |
Leather | Metal | Grease | 0.2 | |
Leather | Wood | Clean and Dry | 0.3 – 0.4 | |
Leather | Clean Metal | Clean and Dry | 0.6 | |
Leather | Cast Iron | Clean and Dry | 0.6 | 0.56 |
Leather fiber | Cast iron | Clean and Dry | 0.31 | |
Leather fiber | Aluminum | Clean and Dry | 0.30 | |
Magnesium | Magnesium | Clean and Dry | 0.6 | |
Magnesium | Magnesium | Grease | 0.08 | |
Magnesium | Steel | Clean and Dry | 0.42 | |
Magnesium | Cast Iron | Clean and Dry | 0.25 | |
Masonry | Brick | Clean and Dry | 0.6 – 0.7 | |
Mica | Mica | Freshly cleaved | 1.0 | |
Nickel | Nickel | Clean and Dry | 0.7 – 1.1 | 0.53 |
Nickel | Nickel | Grease | 0.28 | 0.12 |
Nickel | Mild Steel | Clean and Dry | 0.64 | |
Nickel | Mild Steel | Grease | 0.178 | |
Nylon | Nylon | Clean and Dry | 0.15 – 0.25 | |
Nylon | Steel | Clean and Dry | 0.4 | |
Nylon | Snow | Wet 0 oC | 0.4 | |
Nylon | Snow | Dry -10 oC | 0.3 | |
Oak | Oak (parallel grain) | Clean and Dry | 0.62 | 0.48 |
Oak | Oak (cross grain) | Clean and Dry | 0.54 | 0.32 |
Oak | Oak (cross grain) | Grease | 0.072 | |
Paper | Cast Iron | Clean and Dry | 0.20 | |
Phosphor-bronze | Steel | Clean and Dry | 0.35 | |
Platinum | Platinum | Clean and Dry | 1.2 | |
Platinum | Platinum | Grease | 0.25 | |
Plexiglas | Plexiglas | Clean and Dry | 0.8 | |
Plexiglas | Plexiglas | Grease | 0.8 | |
Plexiglas | Steel | Clean and Dry | 0.4 – 0.5 | |
Plexiglas | Steel | Grease | 0.4 – 0.5 | |
Polystyrene | Polystyrene | Clean and Dry | 0.5 | |
Polystyrene | Polystyrene | Grease | 0.5 | |
Polystyrene | Steel | Clean and Dry | 0.3 – 0.35 | |
Polystyrene | Steel | Grease | 0.3 – 0.35 | |
Polyethylene | Polytehylene | Clean and Dry | 0.2 | |
Polyethylene | Steel | Clean and Dry | 0.2 | |
Polyethylene | Steel | Grease | 0.2 | |
Rubber | Rubber | Clean and Dry | 1.16 | |
Rubber | Cardboard | Clean and Dry | 0.5 – 0.8 | |
Rubber | Dry Asphalt | Clean and Dry | 0.9 | 0.5 – 0.8 |
Rubber | Wet Asphalt | Clean and Dry | 0.25 – 0.75 | |
Rubber | Dry Concrete | Clean and Dry | 0.6 – 0.85 | |
Rubber | Wet Concrete | Clean and Dry | 0.45 – 0.75 | |
Silk | Silk | Clean | 0.25 | |
Silver | Silver | Clean and Dry | 1.4 | |
Silver | Silver | Grease | 0.55 | |
Sapphire | Sapphire | Clean and Dry | 0.2 | |
Sapphire | Sapphire | Grease | 0.2 | |
Silver | Silver | Clean and Dry | 1.4 | |
Silver | Silver | Grease | 0.55 | |
Skin | Metals | Clean and Dry | 0.8 – 1.0 | |
Steel | Steel | Clean and Dry | 0.5 – 0.8 | 0.42 |
Steel | Steel | Grease | 0.16 | |
Steel | Steel | Castor oil | 0.15 | 0.081 |
Steel | Steel | Stearic Acid | 0.15 | |
Steel | Steel | Light mineral oil | 0.23 | |
Steel | Steel | Lard | 0.11 | 0.084 |
Steel | Steel | Graphite | 0.058 | |
Steel | Graphite | Clean and Dry | 0.21 | |
Straw Fiber | Cast Iron | Clean and Dry | 0.26 | |
Straw Fiber | Aluminum | Clean and Dry | 0.27 | |
Tarred fiber | Cast Iron | Clean and Dry | 0.15 | |
Tarred fiber | Aluminum | Clean and Dry | 0.18 | |
Polytetrafluoroethylene (PTFE) (Teflon) | Polytetrafluoroethylene (PTFE) | Clean and Dry | 0.04 | 0.04 |
Polytetrafluoroethylene (PTFE) | Polytetrafluoroethylene (PTFE) | Grease | 0.04 | |
Polytetrafluoroethylene (PTFE) | Steel | Clean and Dry | 0.05 – 0.2 | |
Polytetrafluoroethylene (PTFE) | Snow | Wet 0 oC | 0.05 | |
Polytetrafluoroethylene (PTFE) | Snow | Dry 0 oC | 0.02 | |
Tungsten Carbide | Steel | Clean and Dry | 0.4 – 0.6 | |
Tungsten Carbide | Steel | Grease | 0.1 – 0.2 | |
Tungsten Carbide | Tungsten Carbide | Clean and Dry | 0.2 – 0.25 | |
Tungsten Carbide | Tungsten Carbide | Grease | 0.12 | |
Tungsten Carbide | Copper | Clean and Dry | 0.35 | |
Tungsten Carbide | Iron | Clean and Dry | 0.8 | |
Tin | Cast Iron | Clean and Dry | 0.32 | |
Tire, dry | Road, dry | Clean and Dry | 1 | |
Tire, wet | Road, wet | Clean and Dry | 0.2 | |
Wax, ski | Snow | Wet 0 oC | 0.1 | |
Wax, ski | Snow | Dry 0 oC | 0.04 | |
Wax, ski | Snow | Dry -10 oC | 0.2 | |
Wood | Clean Wood | Clean and Dry | 0.25 – 0.5 | |
Wood | Wet Wood | Clean and Dry | 0.2 | |
Wood | Clean Metal | Clean and Dry | 0.2 – 0.6 | |
Wood | Wet Metals | Clean and Dry | 0.2 | |
Wood | Stone | Clean and Dry | 0.2 – 0.4 | |
Wood | Concrete | Clean and Dry | 0.62 | |
Wood | Brick | Clean and Dry | 0.6 | |
Wood – waxed | Wet snow | Clean and Dry | 0.14 | 0.1 |
Wood – waxed | Dry snow | Clean and Dry | 0.04 | |
Zinc | Cast Iron | Clean and Dry | 0.85 | 0.21 |
Zinc | Zinc | Clean and Dry | 0.6 | |
Zinc | Zinc | Grease | 0.04 |
Source: The Engineering ToolBox (2004). Friction Coefficients – Common Materials and Surfaces. [online] Available at: https://www.engineeringtoolbox.com/friction-coefficients-d_778.html May 7, 2025.