Influence of structural and phase composition on mechanical characteristics of laser welded joints of aluminium-lithium alloys

Abstract

Abstract The paper presents the analysis of the structural and phase composition by the methods of electronic microscopy, X-ray diffraction analysis and synchrotronic radiation of the laser welded joints for the Al-Li alloys of the systems Al-Cu-Li and Al-Mg-Li without and after the post thermal treatment. It is shown that during the welding, strengthening phases dilute in the solid solution of the welded joint, and, in the case of Al-Cu-Li alloys, they concentrate over the dendrite boundary. The optimal post heat treatment restores the structural phase composition and mechanical properties of the weld.