Mn Content-Dependent Processing Window, Microstructural Evolution, and Tensile Behavior of Selective Laser Melted Al-Mn-Sc High-Strength Aluminum Alloys

The Al-Mn-Sc alloy is notable for its high strength, corrosion resistance, and brittleness, making it suitable for aerospace and automotive applications. This study investigates how varying manganese (Mn) content influences the alloy's processability and mechanical properties using selective laser melting (SLM). Increasing Mn content broadens the process parameter window, enhancing hardness and mechanical strength due to solid solution strengthening. Aging heat treatments at 300°C optimize properties, achieving significant yield and ultimate tensile strengths. However, excessive Mn can cause brittleness, impacting ductility. The research aims to refine alloy composition for better performance, providing insights into defect formation and microstructural changes.