Uniting high strength with large ductility in an additively manufactured fine-grained aluminum alloy

Actualizing the near net-shaping of lightweight aluminum (Al) alloys with both superior mechanical performance and complex geometry remains challenging. To address this issue, novel Al-Ti-C-B (TCB) master alloy powders were tailored as effective inoculators and introduced into the AlSi10Mg alloy powders to promote the heterogeneous nucleation of alpha-Al during powder bed fusion using laser beam (PBF-LB), leading to pronounced heterogeneous microstructure with bimodal fine-grains and improved distribution of eutectic Si. The modified alloy with a more refined and homogeneous microstructure exhibited an excellent strength-ductility combination due to microstructure modification, outperforming most previously reported commercial Al-Si alloys.