Investigating the Influence of process parameters on the mechanical and microstructure properties of graphene reinforced aluminium metal matrix manufactured by selective laser melting

Additive Manufacturing (AM) is a rapidly evolving technique that offers diverse opportunities for the manufacturing sector to improve the fabrication of metals, alloys, composites, and polymers. AM has demonstrated a promising approach in achieving superior properties in aluminium and aluminium alloy composites reinforced with SiC, TiC, TiB2, and Al2O3 etc. In recent times, graphene has also emerged as a potential reinforcement for metals due to its exceptional mechanical properties. This study examines the mechanical and microstructural properties of AlSi10Mg reinforced with 0.1% graphene, fabricated using a selective laser melting (SLM) process. The influence of process parameters such as laser power (200–400W), layer thickness (30 μm-60 μm), and hatch spacing (50–90 μm) has been investigated on density, porosity, hardness, microstructure and tensile properties. The results reveal that increasing the volumetric energy density (VED) enhances the mechanical properties of the material. The porosity achieves a minimum value after reaching a threshold VED, indicating optimum densification. Additionally, tensile strength, elongation, and hardness of the composite improve with higher laser power, while tensile strength initially rises and then declines as hatch spacing increases. A lower layer thickness yields superior properties, with optimum hardness values achieved at a 70 μm hatch spacing.