Microscale friction and wear at rock salt-type single crystal surfaces

Abstract

The anisotropy in nanoscale friction on rock salt-type crystal surfaces can be interpreted intuitively by the atomic arrangements. In the microscale, however, participation of plastic deformation has given much more complexity. This time, we have measured friction with a sapphire stylus, and observed wear patterns, with optical and atomic force microscopies, at low-index single crystal surfaces of MgO and LiF. Dependence of wear patterns upon material, crystal faces, scan directions and the levels of normal load were studied. The mechanisms of plastic deformation are discussed.