Study of nanoscratching of polymers by using molecular dynamics simulations

Molecular dynamic simulations are performed to study the nanoscratching behavior of polymers. The effects of scratching depth, scratching velocity and indenter/polymer interaction strength are investigated. It is found that polymer material in the scratching zone around the indenter can be removed in a ductile manner as the local temperature in the scratching zone exceeds glass transition temperature T _g . The recovery of polymer can be more significant when the temperature approaches or exceeds T _g . The tangential force, normal force and friction coefficient increase as the scratching depth increases. A larger scratching velocity leads to more material deformation and higher pile-up. The tangential force and normal force are larger for a larger scratching velocity whereas the friction coefficient is almost independent of the scratching velocities studied. It is also found that stronger indenter/polymer interaction strength results in a larger tangential force and friction coefficient.