Effect of Mg Content on the Mechanical and Corrosion Behavior of AlSi10Mg <i>x</i> Alloys via Selective Laser Melting

ABSTRACT This study systematically investigated the effect of Mg content (0.5%, 1.8%, and 3.5%) on the microstructure, mechanical properties, and corrosion behavior of AlSi10 alloys fabricated via selective laser melting (SLM). Microstructural characterization via scanning electron microscopy and energy dispersive X‐ray spectroscopy (SEM/EDS) revealed that an increase in Mg content impairs the continuity of the Si network. The most severe disruption is observed in SLM AlSi10Mg3.5, accompanied by Mg aggregation. Tensile tests showed that higher Mg content improved yield strength (up to ~350 MPa in AlSi10Mg3.5) but reduced ductility. Electrochemical tests conducted in 3.5 wt.% NaCl solution demonstrated that SLM AlSi10Mg3.5 has the highest corrosion current density, whereas AlSi10Mg0.5 exhibited the best corrosion resistance. A kinetic model based on the univalent Mg (Mg + ) was used to interpret the EIS data. Overall, a Mg content of 0.5% achieved an effective balance between mechanical properties and corrosion resistance.