Layer thickness optimization for enhanced productivity in PBF-LB of AISI 316 L meeting standard strength requirements

The powder bed fusion laser beam (PBF-LB) technology played an essential role in the evolution of additive manufacturing (AM), particularly for its ability to build complex, challenging, and high-quality metal components. However, enhancing PBF-LB productivity and lowering its costs can help to fulfill its potential. Some studies have shown that increasing layer thickness can significantly impact productivity and that better results are achieved with fine powder. Only a few studies have systematically optimized layer thickness, accounting for its interactions with other parameters while balancing productivity and mechanical properties. Therefore, this work employed a series of experiments using commercial-grade AISI 316 L stainless steel powder to establish a process window that improves productivity and cost-efficiency without compromising standard mechanical requirements. The methodology began with single tracks followed by cube studies, whose porosity was used to create a regression model. The optimized set of parameters predicted by the model was then selected for mechanical evaluation via tensile and impact tests and compared with reference samples and standard requirements. The results showed a refined microstructure, and tensile and impact testing met the main requirements of the specific standard, although pore volume increased. A significant 59% productivity increase was mainly attributed to reduced laser scanning and spreading time, resulting from fewer layers, leading to an estimated 55.8% reduction in manufacturing cost.