Microstructural evolution of the deformed volume beneath microindents in tungsten and copper

In order to characterize the deformed volume beneath microindents in tungsten and copper, several cross-sections through the indents were machined using a focused ion beam workstation. Electron backscattering diffraction scans were performed on these cross-sections to determine local orientations and changes of orientation due to plastic deformation with respect to the undeformed crystal. It was found that the deformation is highly localized beneath the tip and flanks of the indent. For small indentations a constant ratio between the maximum misorientation beneath the indent flanks and the diameter of the imprint was found. This conflicts with the idea of self-similar deformation.