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Specimens of 316 L stainless steel were printed using laser powder bed fusion (LPBF), a popular metal additive manufacturing (AM) technique, with varying island sizes. Not many researchers have considered the impact of spatter while optimizing LPBF printing parameters. In this research, the influence of spatter was considered while also investigating the effect of varied island size on the microstructure, surface roughness, microhardness, and corrosion resistance of LPBF-316 L. No correlation was observed between surface roughness or microhardness and minor variations in island size. However, a correlation was drawn between varied island sizes and porosity in LPBF-316 L. The specimens associated with larger island sizes showed significantly enhanced corrosion resistance due to fewer manufacturing defects and reduced porosity, attributed to the minimal influence of the spatter. Based on analysis, the LPBF parameters were revised, which lead to superior corrosion resistance of LPBF-316 L, attributed to high density and reduced porosity.

Mechanically alloyed Fe-based alloys with oxide dispersion strengthening have largely dropped out of the marketplace due to high cost related to problems with complex and unreliable processing. Nevertheless, the desirable properties of oxide dispersion strengthened (ODS) steels have motivated research on alternate processing routes aimed at improving processing simplicity and reliability. Powders produced by gas atomization reaction synthesis (GARS) consist of stable Fe-Y intermetallic phases and a Cr surface oxide layer that acts as a chemical reservoir during solid-state processing and heat treatment to form a high density of nano-scale oxides. This research explores the use of Fe GARS powders, with 15 wt% Cr with micro-alloyed additions of 0.15 wt% Y and 0.10% Ti, in laser powder bed fusion (LPBF) additive manufacturing (AM), and evaluates the effectiveness of oxide dispersoid formation in the liquid melt pool. Additional oxygen was introduced by varying the LPBF chamber atmospheres using Ar, Ar + 1 wt% O, Ar + 5 wt% O, and air. Characterization of LPBF consolidated solids demonstrated the formation of a high density of nano-scale Y-Ti oxides in the build microstructures from the GARS precursor powders.