Using synchrotron X-ray diffraction the residual stress distribution has been measured in a series of AA7449-W51 aluminium friction stir welds that had been tensioned to different loads during welding. By modifying the stress accumulation path, the application of a tensioning stress has reduced the tensile magnitude of the final residual weld stresses. In the present case the residual stresses were minimised when the applied load is 35% of the room temperature yield stress of the parent material. Subsequent sectioning of the weld into shorter test lengths, as might be necessary for weld testing, resulted in a progressive and significant relaxation of the residual stress field. The effect of tensioning on the weld component distortion also has been investigated.
|Translated title of the contribution||The effect of tensioning and sectioning on residual stresses in aluminium AA7749 friction stir welds|
|Pages (from-to)||16 - 24|
|Number of pages||9|
|Journal||Materials Science and Engineering: A|
|Publication status||Published - Aug 2008|