TWI Industrial Member Report Summary 861/2007
Part B Autogenous Yb-fibre laser and hybrid Yb-fibre laser-MIG welding of 12.7mm thickness alloy
By G Verhaeghe
Background
Based on their experience in thin-section fuselage structures, Airbus UK established a strategy for the development of fusion welding methods for wing structures, resulting in a UK government DTI supported collaborative project, named DEFUSE. The primary aim of the DEFUSE consortium, led by TWI and comprising several industrial companies and universities, was to investigate novel technologies for the welding of thick-section aluminium wing structures. The work presented in this report comprises an investigation into the suitability of laser welding for aluminium wing manufacture, using a 7000-series Al-Mg-Zn-Cu alloy of proprietary composition and temper, further referred to as 7xxx. The aim of the investigation was to achieve full penetration in 12.7mm thickness plate, with a resulting laser weld quality, in particular related to weld metal porosity, suitable for aerospace service.
Objectives
- To establish welding conditions to obtain full penetration in 12.7mm thickness 7xxx aluminium, in a single pass, using autogenous laser and/or hybrid laser-MIG welding.
- To achieve a weld quality in 12.7mm thickness 7xxx aluminium, in particular related to weld metal porosity, in line with the limits of the stringent weld quality classes defined in both BS EN 13919-2 and AWS D17.1.