Neutron and synchrotron x-ray diffraction strain measurements around gas tungsten arc and electron beam welds are used to characterise the state of residual stress in an aero-engine component and testpieces in wrought nickel-base super-alloys. Spatial resolution is typically found to be around 1 mm and typical counting times are around 15 minutes per orientation for neutron diffraction and 10s for synchrotron x-rays. The effects of intergranular, orientation-dependent strains are discussed and their avoidance in the determination of engineering strain illustrated. Grain size and beam divergence are found to limit the spatial resolution that can be achieved, and this illustrates why in-weld measurements made using these techniques can be unreliable. These effects are explored using case studies in gas tungsten arc, electron beam and low stress low distortion welds in IN718 and C263 and electron-beam welds in a Waspaloy plate and compressor disc assembly.
|Number of pages||8|
|Publication status||Published - 2002|
|Event||Trends in Welding Research: Proceedings of the 6th International Conference - Phoenix, AZ, United States|
Duration: 15 Apr 2002 → 19 Apr 2002
|Conference||Trends in Welding Research: Proceedings of the 6th International Conference|
|Period||15/04/02 → 19/04/02|