#it would be nice to find some explicitly free source of material data, perhaps CRC handbook or NIST? url: http://www.school-for-champions.com/science/friction_coefficient.htm aluminum: aluminum: kinetic_max: 1.4 kinetic_min: 1.4 static_max: 1.35 static_min: 1.05 mild steel: kinetic_max: 0.47 kinetic_min: 0.47 static_max: 0.61 static_min: 0.61 brake material: cast iron: kinetic_max: null kinetic_min: null static_max: 0.4 static_min: 0.4 cast iron (wet): kinetic_max: null kinetic_min: null static_max: 0.2 static_min: 0.2 brass: cast iron: kinetic_max: 0.3 kinetic_min: 0.3 static_max: null static_min: null brick: wood: kinetic_max: null kinetic_min: null static_max: 0.6 static_min: 0.6 bronze: cast iron: kinetic_max: 0.22 kinetic_min: 0.22 static_max: null static_min: null steel: kinetic_max: null kinetic_min: null static_max: null static_min: null cadmium: cadmium: kinetic_max: null kinetic_min: null static_max: 0.5 static_min: 0.5 mild steel: kinetic_max: 0.46 kinetic_min: 0.46 static_max: null static_min: null cast iron: cast iron: kinetic_max: 0.15 kinetic_min: 0.15 static_max: 1.1 static_min: 1.1 oak: kinetic_max: 0.49 kinetic_min: 0.49 static_max: null static_min: null chromium: chromium: kinetic_max: null kinetic_min: null static_max: 0.41 static_min: 0.41 copper: cast iron: kinetic_max: 0.29 kinetic_min: 0.29 static_max: 1.05 static_min: 1.05 copper: kinetic_max: null kinetic_min: null static_max: 1.0 static_min: 1.0 mild steel: kinetic_max: 0.36 kinetic_min: 0.36 static_max: 0.53 static_min: 0.53 copper-lead alloy: steel: kinetic_max: null kinetic_min: null static_max: 0.22 static_min: 0.22 diamond: diamond: kinetic_max: null kinetic_min: null static_max: 0.1 static_min: 0.1 metal: kinetic_max: null kinetic_min: null static_max: 0.15 static_min: 0.1 glass: glass: kinetic_max: 0.4 kinetic_min: 0.4 static_max: 1.0 static_min: 0.9 metal: kinetic_max: null kinetic_min: null static_max: 0.7 static_min: 0.5 nickel: kinetic_max: 0.56 kinetic_min: 0.56 static_max: 0.78 static_min: 0.78 graphite: graphite: kinetic_max: null kinetic_min: null static_max: 0.1 static_min: 0.1 steel: kinetic_max: null kinetic_min: null static_max: 0.1 static_min: 0.1 graphite (in vacuum): graphite (in vacuum): kinetic_max: null kinetic_min: null static_max: 0.8 static_min: 0.5 hard carbon: hard carbon: kinetic_max: null kinetic_min: null static_max: 0.16 static_min: 0.16 steel: kinetic_max: null kinetic_min: null static_max: 0.14 static_min: 0.14 iron: iron: kinetic_max: null kinetic_min: null static_max: 1.0 static_min: 1.0 lead: cast iron: kinetic_max: 0.43 kinetic_min: 0.43 static_max: null static_min: null leather: metal (clean): kinetic_max: null kinetic_min: null static_max: 0.6 static_min: 0.6 metal (wet): kinetic_max: null kinetic_min: null static_max: 0.4 static_min: 0.4 oak (parallel grain): kinetic_max: 0.52 kinetic_min: 0.52 static_max: 0.61 static_min: 0.61 wood: kinetic_max: null kinetic_min: null static_max: 0.4 static_min: 0.3 magnesium: magnesium: kinetic_max: null kinetic_min: null static_max: 0.6 static_min: 0.6 nickel: mild steel: kinetic_max: 0.64 kinetic_min: 0.64 static_max: null static_min: null nickel: kinetic_max: 0.53 kinetic_min: 0.53 static_max: 1.1 static_min: 0.7 nylon: nylon: kinetic_max: null kinetic_min: null static_max: 0.25 static_min: 0.15 oak: oak (cross grain): kinetic_max: 0.32 kinetic_min: 0.32 static_max: 0.54 static_min: 0.54 oak (parallel grain): kinetic_max: 0.48 kinetic_min: 0.48 static_max: 0.62 static_min: 0.62 platinum: platinum: kinetic_max: null kinetic_min: null static_max: 1.2 static_min: 1.2 plexiglas: plexiglas: kinetic_max: null kinetic_min: null static_max: 0.8 static_min: 0.8 steel: kinetic_max: null kinetic_min: null static_max: 0.5 static_min: 0.4 polystyrene: polystyrene: kinetic_max: null kinetic_min: null static_max: 0.5 static_min: 0.5 steel: kinetic_max: null kinetic_min: null static_max: 0.35 static_min: 0.3 polythene: steel: kinetic_max: null kinetic_min: null static_max: 0.2 static_min: 0.2 rubber: asphalt (dry): kinetic_max: 0.8 kinetic_min: 0.5 static_max: null static_min: null asphalt (wet): kinetic_max: 0.75 kinetic_min: 0.25 static_max: null static_min: null concrete (dry): kinetic_max: 0.85 kinetic_min: 0.6 static_max: null static_min: null concrete (wet): kinetic_max: 0.75 kinetic_min: 0.45 static_max: null static_min: null sapphire: sapphire: kinetic_max: null kinetic_min: null static_max: 0.2 static_min: 0.2 silver: silver: kinetic_max: null kinetic_min: null static_max: 1.4 static_min: 1.4 sintered bronze: steel: kinetic_max: null kinetic_min: null static_max: null static_min: null solids: rubber: kinetic_max: null kinetic_min: null static_max: 4.0 static_min: 1.0 steel: aluminum bros: kinetic_max: null kinetic_min: null static_max: 0.45 static_min: 0.45 brass: kinetic_max: null kinetic_min: null static_max: 0.35 static_min: 0.35 cast iron: kinetic_max: null kinetic_min: null static_max: 0.4 static_min: 0.4 copper lead alloy: kinetic_max: null kinetic_min: null static_max: 0.22 static_min: 0.22 graphite: kinetic_max: null kinetic_min: null static_max: 0.1 static_min: 0.1 phos bros: kinetic_max: null kinetic_min: null static_max: 0.35 static_min: 0.35 zinc (plated on steel): kinetic_max: 0.45 kinetic_min: 0.45 static_max: 0.5 static_min: 0.5 steel (hard): graphite: kinetic_max: null kinetic_min: null static_max: 0.21 static_min: 0.21 polystyrene: kinetic_max: null kinetic_min: null static_max: 0.35 static_min: 0.3 polythene: kinetic_max: null kinetic_min: null static_max: 0.2 static_min: 0.2 steel (hard): kinetic_max: 0.42 kinetic_min: 0.42 static_max: 0.78 static_min: 0.78 steel (mild): brass: kinetic_max: 0.44 kinetic_min: 0.44 static_max: 0.51 static_min: 0.51 cast iron: kinetic_max: 0.23 kinetic_min: 0.23 static_max: null static_min: null lead: kinetic_max: 0.95 kinetic_min: 0.95 static_max: 0.95 static_min: 0.95 phos. bros: kinetic_max: 0.34 kinetic_min: 0.34 static_max: null static_min: null steel (mild): kinetic_max: 0.57 kinetic_min: 0.57 static_max: 0.74 static_min: 0.74 teflon: steel: kinetic_max: null kinetic_min: null static_max: 0.04 static_min: 0.04 teflon: kinetic_max: null kinetic_min: null static_max: 0.04 static_min: 0.04 tin: cast iron: kinetic_max: .32 kinetic_min: .32 static_max: null static_min: null tungsten carbide: copper: kinetic_max: null kinetic_min: null static_max: 0.35 static_min: 0.35 iron: kinetic_max: null kinetic_min: null static_max: 0.8 static_min: 0.8 steel: kinetic_max: null kinetic_min: null static_max: 0.6 static_min: 0.4 tungsten carbide: kinetic_max: null kinetic_min: null static_max: 0.25 static_min: 0.2 wood: brick: kinetic_max: null kinetic_min: null static_max: 0.6 static_min: 0.6 concrete: kinetic_max: null kinetic_min: null static_max: 0.62 static_min: 0.62 metals (clean): kinetic_max: null kinetic_min: null static_max: 0.6 static_min: 0.2 metals (wet): kinetic_max: null kinetic_min: null static_max: 0.2 static_min: 0.2 wood (clean): kinetic_max: null kinetic_min: null static_max: 0.5 static_min: 0.25 wood (wet): kinetic_max: null kinetic_min: null static_max: 0.2 static_min: 0.2 zinc: cast iron: kinetic_max: 0.21 kinetic_min: 0.21 static_max: 0.85 static_min: 0.85 zinc: kinetic_max: null kinetic_min: null static_max: 0.6 static_min: 0.6