Friction Has Memory, Say Physicists

June 20, 2018

Light entering the lower slab of plastic reflects off its upper surface but also passes into the upper slab in spots where there is close contact at the interface. The technique reveals the true contact area between the two slabs, an important parameter in determining friction. (S. Dillavou and S. Rubinstein/Harvard Univ.)

Experiments by [graduate student] Sam Dillavou and Shmuel Rubinstein [SEAS] at Harvard University have, for the first time, revealed that the friction between two surfaces has a “memory”. This means that the force can depend not only on the present state of the interface but also on how the interface has reached its current state. This new insight could have a bearing on how physicists characterize friction in materials such as rock, metals and paper and apply to a wide range of physical systems from micromachines to earthquakes...

Continue reading "Friction has memory, say physicists," physicsworld.com, 19 June 2018. https://physicsworld.com/a/friction-has-memory-say-physicists/.

Read the research article, featured in Physics, here:
Sam Dillavou and Shmuel M. Rubinstein, "Nonmonotonic Aging and Memory in a Frictional Interface," Phys. Rev. Lett. 120 (2018) doi: https://doi.org/10.1103/PhysRevLett.120.224101.