| Abstract Scope |
Rapid solidification (RS) enhances solute trapping in Al-10Si-0.4Sc (wt%) alloys, promoting partitionless solidification. A universal metric is essential for tailoring microstructures across manufacturing processes. A Universal Solidification Map (USM) was developed that uses a novel metric, percent solute trapped, to link solute partitioning with growth kinetics. Integrating data from near-equilibrium processing, brazing, impulse atomization (IA), laser powder bed fusion (LPBF), selective laser melting (SLM), and pulsed laser melting (PLM), the USM defines four regimes: Near Equilibrium, Lower Quasi-Rapid, Higher Quasi-Rapid, and Absolute Partitionless. Transition to Higher Quasi-Rapid occurs at ~10% solute trapping (dendrite velocity V≅0.02 m/s and undercooling ∆T≅155 K), with dendrite orientation shifting from ⟨100⟩ to ⟨320⟩. Complete Sc trapping predicted at ~10 m/s suppressing undesirable AlSc2Si2 intermetallic. The USM enables predictive process mapping and microstructure tuning in Al-Si alloys, with applicability to diverse alloy systems for advanced solidification process design. |