TG7: Electron beam weld on a high strength Al alloy


An aluminium alloy (AA6061 T6 – Al-Mg-Si precipitation hardened alloy of the 6xxx series) with an autogenous electron beam weld along the middle of the specimen is being studied by Task Group 7.

 

The 6061 alloy is a high strength aluminium alloy thanks to a specific heat treatment to obtain the largest density of hardening β’’ precipitates (i.e. T6 state). In order to have realistic welding conditions and also get reproducible results, a fusion line was performed on different 6061-T6 plates with different welding velocities. The dimensions of the plates are 200 x 180 x 20 mm3. The thermal cycles above 200°C change drastically the microstructure leading to a modification of the mechanical behaviour of the alloy (softening and natural ageing) and thus having consequences on typical residual stress profiles for such a weld configuration in comparison with steel. The specimen can be used both for material and microstructure model calibration and residual stress measurements.


A circular specimen (thickness is 40 mm at welding stage prior to machining to 20 mm) is also available to check differences between stress profile obtained with straight and circular welds.

TG7.JPG

Network on Neutron Techniques Standarization for Structural Integrity