Influence of irregularities at butt-welded seams on the behaviour of the vibration-fatigue strength of sheet-aluminium joints

摘要

For quality-assurance purposes in lightweight construction, assured dynamic-strength values are being demanded for welded joints made of sheet aluminium. However, the applicable standards for the classification of welding-seam irregularities (imperfections) in the assessment groups currently refer to the plate-thickness range of 3 to 63 mm only. The behaviour of the vibration-fatigue strength of sheet-aluminium joints was therefore investigated in order to be able to extend the rules and standards for lower sheet thicknesses. The joints were manufactured by means of inert-gas metal-arc welding and laser-beam welding. During this pro-cess, imperfections were produced deliberately. With the results of the vibration-fatigue-strength investigations and with those results already available for inert-gas tungsten-arc welding, it is planned to prepare a drqft for the classification of welding-seam imperfec-tions in the assessment groups of aluminium joints for the sheet-metal range.