Simultaneously enhancing strength and ductility of selective laser melted AlSi10Mg via introducing in-cell Al₄C₃ nanorods

Selective laser melted (SLMed) AlSi10Mg alloys usually fail before necking during tensile tests, which results in inadequate ductility. To overcome this problem, here we introduced Al₄C₃ nanorods into the primary Al cells of SLMed AlSi10Mg via in-situ chemical reaction. Tensile tests revealed that those in-cell Al₄C₃ nanorods not only increased the strain-hardening ability of SLMed AlSi10Mg but also delayed the fracture beyond necking. Consequently, 15% of tensile strength increase and 78% of ductility increase were achieved simultaneously. Post-tensile TEM analysis revealed that those in-cell Al₄C₃ nanorods pinned and accumulated dislocations within cells and thus alleviated stress concentration along cell boundaries.