Residual stress analysis

Nanocrystalline materials are currently the subject of intensive investigations because of their wide application in modern semiconductor, coating, optics and other industries. X-ray diffraction methods are ideally suited for the investigation of such nanoscale structures since the diffraction pattern delivers information on both the crystalline structure and the perfection of the nanocrystalline domains as well as on the dislocation distribution, crystallite size, micro-strain within the grains, etc.

We investigate the dependence of the deformation behaviour (both elastic and plastic) as a function of the strain applied to nanocrystalline Pd thin films. The deformation behaviour within the samples has been studied by using in-situ X-ray diffraction techniques at the synchrotron radiation source ANKA. The position and the shape of the X-ray diffraction peaks are interpreted in terms of micro-strain, grain size, grain size distribution, and dislocation density in dependence on the applied strain.

The analysis of the obtained data delivers the status of the residual micro- and macrostress as well as the texture (crystallite orientation distribution) in the sample.