Impact of Print Orientation on Morphological and Mechanical Properties of L-PBF Based AlSi7Mg Parts for Aerospace Applications

The Laser-Powder Bed Fusion (L-PBF) based AlSi7Mg parts are adopted for the aerospace industries, especially for making antenna, RF components, gyroscopes, and waveguides. The primary use of additive manufacturing in the aerospace industry is because it enables producing very lightweight components with complex designs. However, the mechanical properties of manufactured L-PBF components are not yet fully validated because numerous challenges posed by the process itself and defects that occur on the manufactured materials by L-PBF. In this research, to further elucidate the printing mechanism of AlSi7Mg lightweight alloy a detailed investigation was carried out to analyze the influence of print orientation on the physical, morphological, and mechanical behavior of L-PBF based AlSi7Mg parts. AlSi7Mg parts were manufactured with various print orientations from vertical, inclined and horizontal. The fabricated parts were analyzed for microstructural behavior using an optical microscope (OM), and scanning electron microscope (SEM) with energy dispersive X-ray analysis (EDAX) proving the elemental composition of the AlSi7Mg parts were studied. Mechanical testing such as tensile, hardness, wear, fracture toughness, and shear tests was carried out for various orientations manufactured in order to evaluate their properties. The vertically-oriented AlSi7Mg parts shows 13.8 %, 58.4 % and 7.9 % higher tensile, toughness and shear strength when compared with the horizontally-oriented parts. But the maximum wear resistance was observed in the horizontal parts and it was 52.9 % higher wear resistance than the vertical parts. The results can be used as a guide in the aerospace industry in order to design components with high structural integrity.