Effect of Layer Thickness in Selective Laser Melting on Microstructure of Al/5 wt.%Fe₂O₃ Powder Consolidated Parts

Table 1

Summary of microstructural evolution in the dependence of layer thickness, laser power, and scanning speed.

	Thick powder bed	𝑡=75 𝜇m	𝑡=50 𝜇m
Morphology (appearance)	Single Al phase-granular structure	Predominantly coralline-like	Semicoralline-like/particulate
Oxygen/oxide content	Least oxygen/oxide	Medium oxygen/oxide	Highest oxygen/oxide
Predominant phases	Al	Al, Al-Fe intermetallics such as Al13Fe4 and Fe3Al; some oxides (like Fe^2+Al2O4) may also be detected	Al, aluminium oxide (Al2O3) plus iron aluminium oxides (e.g. Fe^2+Al2O4 and AlFeO3), Al-Fe intermetallics such as Al13Fe4
Increasing laser power	N/A	Development of corallines (mainly Al-Fe intermetallics) and oxide particles from primary Al/Fe2O3 interface—reduction in oxygen/oxide	N/A
Lowering scanning speed	N/A	Coarsening of corallines—reduction in oxygen/oxide	Better dispersion and placement of secondary phases