Statistical approach for assessing the effect of powder reuse on the final quality of AlSi10Mg parts produced by laser powder bed fusion additive manufacturing

The laser powder bed fusion (L-PBF) technique for metals is used in the field of additive manufacturing (AM) processes for the production of functional parts starting from metal powders. Due to the high cost of raw materials and the strong impact of their characteristics on the whole process, it leads essentially to exploit the possibility of reusing residual powder a certain number of times, while ensuring high part performances and productivity. This paper introduces the implementation of a statistical approach for assessing the effect of powder reuse on the mechanical properties and the surface quality of AlSi10Mg parts additively manufactured. Design of experiments (DOE) concepts and the pre-design guide sheets are used to define an accurate procedure and perform a reliable experimentation, while the one-way analysis of variance (ANOVA) and several graphical tools are used to analyse and summarise the experimental results. The effect of powder reuse showed statistical significance in terms of yield strength and ultimate tensile strength. Nonetheless, both the static and the cyclic mechanical properties of the produced samples exhibited small variability and compliance with the company specifications up to the last printing run.