Strong yet ductile heat-resistant aluminum alloy by additive manufacturing

Aluminum (Al) alloys are pivotal structural materials, indispensable for advanced energy-saving solutions and lightweight technologies. However, the limited heat resistance and low critical strength of the present commercial Al alloys at elevated temperatures (300-400 °C) have constrained their broader applications. Here, we present a facile strategy to additively manufacture strong yet ductile heat-resistant Al alloys using laser powder bed fusion (PBF-LB). By embedding heat-resistant multicomponent intermetallic nanophases (HMINPs) at the solidified cell boundaries, the as-printed alloy forms thermally stable cellular structures containing a high-volume fraction (~14 vol%) of HMINPs. Without any additional post-treatment, our as-printed Al alloy exhibits an average room-temperature tensile strength of 582 MPa, combined with a tensile strength of 114 MPa and exceptional creep resistance at 400 °C. The partial solid-state amorphization of the HMINPs during tensile straining at 300-400 °C creates a nano-dual-phase glass-crystal structure, providing an additional toughening mechanism. This HMINP strategy and PBF-LB's freeform manufacturing capability enable large-scale industrial use of our high-performance Al alloy, holding great promise for advancing energy efficiency, carbon neutrality, and sustainable manufacturing.