Identification of Load Induced Inhomogeneous Plastic Deformations in Aluminium Welds by Diffraction Methods

Abstract

Cold formed and precipitation hardened aluminium alloys welded with arc welding and electron beam welding processes have been investigated to analyse the local deformation behaviour under static and cyclic loads. Therefore lateral strain measurements with different techniques have been carried out in the surrounding of the weld seam. The strain measurements were combined with micro hardness measurements in order to determine loading induced local softening and hardening. These investigations were combined with X-ray diffraction experiments which should provide information about the residual stress condition and additionally about load induced changes of the hardening condition by the analysis of the FWHM-values of the diffraction lines. Additionally in-situ diffraction experiments using synchrotron radiation where carried out to analyse the deformation behaviour of particular welds under varying static loads. The paper gives an overview about the experimental procedures and important results and their consequences for the evaluation of such aluminium welds.