Enhancement of energy dispersive residual stress analysis by consideration of detector electronic effects

The effects of the germanium detector electronics on diffraction line patterns is investigated. It is shown that not only the detector resolution and the throughput but also the energy stability depend on both the specific detector settings and the dead time. For a moderate resolution versus throughput setting a correction function is proposed and applied to the near-surface residual stress analysis of three samples with considerably different stress states. It is demonstrated that without the correction function ghost stresses up to hundreds of MPa in the near-surface region are obtained. The correction procedure is verified by conventional X-ray measurements. In conclusion. the authors strongly suggest quantifying the electronic shifts of any individual detector systems prior to the analysis of residual stresses. (c) 2007 Elsevier B.V. All rights reserved.