Artificial ageing and residual strain mapping of high strength Al alloys for Laser powder bed fusion

Al alloys are widely used for light-weight structures and components. When processed by laser powder bed fusion (L-PBF), an additive manufacturing (AM) technology, high-strength Al alloys show sharp hot-crack sensitivity. A common approach to overcome this problem relies on the use of Ti- and Zr-based inoculant phases to form fine equiaxed grains to better accommodate solidification strains. Ti and Zr modify severely the aging behaviour of the alloys, thus new heat treatment routes have to be designed. Here we plan to perform in-situ time-resolved XRD analyses on Al-Cu-Mg-Zr and Al-Cu-Mg-Ti-B alloys to investigate the microstructure and precipitate evolution following different heat treatment routes. Residual strain mapping will be also performed at RT on the same materials after different annealing schedules. The achieved results will be useful for the AM industrial and scientific community to design new high strength Al alloys for L-PBF processes and their relative heat treatments.