Scratching the surface: elastic rotations beneath nanoscratch and nanoindentation tests

This experiment investigated the residual deformation field in the vicinity of nanoscratch tests using two orientations of a Berkovich tip on a (001) Cu single crystal, the deformation of which were compared from indentation, in order to understand the mechanisms behind the tangential sliding.

The lattice rotation fields were mapped using a high-resolution electron backscatter diffraction on cross-sections prepared using a focused ion beam.  The lattice rotation fields were simulated using a phyiscally-based crystal plasticity finite element model, which helped gain insight into the 3D rotation field surrounding the nano-scratch experiment during its transition from an initial static indentation into a steady-state scratch.

It was noted the CPFEM simulations captured the experimental rotation fields with good fidelity, and revealed that the rotations about the scratch direction were reversed as the indenter moved away from the initial indentation.

The full paper is available to read in volume 200 of Acta Materialia.