Stress-relief annealing friendly Fe-based metallic glass-reinforced Al-Si-Mg-Zr alloy fabricated by laser powder bed fusion

To enhance the thermal stability of L-PBF Al-Si-Mg alloy, Fe-based metallic glass powder was mixed with Al-Si-Mg-Zr powder to fabricate a novel alloy via L-PBF. The study systematically investigated the effects of process parameters on processability and the impact of stress-relief annealing (300$<^>{\circ }$degrees C-2h) on the microstructure and mechanical properties. Results showed that metallic glass addition improved surface quality. Plastic deformation was analysed using finite element and molecular dynamics methods. The as-built alloy had a cellular substructure with ${\rm Al}_3$Al3Zr, Si, AlFeMgSi, and AlFeSi phases. Si nanoparticles and stacking faults were observed in alpha-Al cells. The as-built samples had yield strength (YS) of 249 +/- 4 MPa, ultimate tensile strength (UTS) of 434 +/- 6 MPa, and 6.3 +/- 0.3% elongation. Post-annealing, the alloy retained high strength and plasticity with YS of 255 +/- 3 MPa, UTS of 449 +/- 15 MPa, and 7.2 +/- 0.3% elongation, outperforming similar L-PBF Al-Si and Al-Si-Mg alloys.