Micropore evolution in additively manufactured aluminum alloys under heat treatment and inter-layer rolling

Additive manufacturing (AM) of aluminum alloy components has drawn broad attention from industrial customers in recent years. With the advantages of low cost and high deposition rate, wire + arc additive manufacturing (WAAM) has been recognized as a promising AM technology in producing large-scale aluminum alloy structural parts. However, the adverse effect of internal defects on mechanical properties has limited the application of WAAM aluminum alloys. Micropores, as one of the most harmful defects, are normally detrimental to the fatigue, strength, and toughness of aluminum alloys. […] Suppressing of micropores in the WAAM components has attracted considerable attention in recent years. […] The hybrid technique of WAAM + rolling + heat treatment has great potential in promoting mechanical properties of WAAM alloys. The results will provide a theoretical guidance for the design of high-performance WAAM aluminum alloy components.