Fusion welding of high strength aluminium alloys is being widely considered within the commercial aircraft industry as an alternative to established mechanical fastening methods. The objective of the present article is to characterise the microstructural features of metal inert gas (MIG) welded plate of the conventional damage tolerant alloy, 2024-T351. Micromechanical aspects of the fatigue performance of this welded material are then addressed in a companion article. The general microstructure of the MIG weld was studied using optical microscopy and scanning electron microscopy, in association with electron back-scattered diffraction mapping. Columnar dendritic structures at the edge of the fusion zone are seen, with fairly uniform equiaxed dendritic grain structure dominating in the weld centre. Local microstructural conditions of the different elements of the weld have been assessed via micro-hardness and differential scanning calorimetry, identifying the balance between aging, overaging, re-solutionising and re-precipitation occurring across the weld region. Residual stress measurements by laboratory X-ray and synchrotron X-ray diffraction are also discussed, showing stress relaxation and redistribution occurring under loads representative of smooth specimen fatigue testing. The fusion zone is seen to present a tensile residual stress field, with peak longitudinal stress occurring towards the interface with the fusion zone.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Micromechanical aspects of fatigue in a MIG welded aluminium airframe alloy. Part 1. Microstructural characterization


    Contributors:


    Publication date :

    2005


    Size :

    8 Seiten, 17 Quellen




    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English





    Strong aluminium alloy saves airframe weight

    Lukasak, D.A. / Hart, R.M. | Tema Archive | 1991


    Residual stresses in laser beam welded butt joints of the airframe aluminium alloy AA6056

    Staron, P. / Vaidya, W.V. / Kocak, M. et al. | Tema Archive | 2006


    Statistical analysis of fatigue related microstructural parameters for airframe aluminum alloys

    Liao, Min / Chisholm, Kyle / Mahendran, Mario | Tema Archive | 2009


    Marage Steel for Welded Airframe Structure

    Hofstatter, Alfred F. | SAE Technical Papers | 1963