Friction of ice measured using lateral force microscopy

The friction of nanometer thin ice films grown on mica substrates is invest igated using atomic force microscopy (AFM). Friction was found to be of sim ilar magnitude as the static friction of ice reported in macroscopic experi ments. The possible existence of a lubricating film of water due to pressur e melting, frictional heating, and surface premelting is discussed based on the experimental results using noncontact, contact, and lateral force micr oscopy. We conclude that AFM measures the dry friction of ice due to the lo w scan speed and the squeezing out of the water layer between the sharp AFM tip and the ice surface.