Binder Jetting - Reusability of 17-4 PH Stainless Steel Powder

Paper in proceeding, 2022

Binder Jetting (BJT) is a binder-based Additive Manufacturing technology, where only a small fraction of the processed powder is bonded inside the green parts after printing. Unbound powder, which is recovered during the BJT process, is reused for printing. For powder reuse, the resulting changes in the physical and chemical powder properties along with the powder surface conditions strongly affect the reproducibility of the BJT process and its final part properties. In this study, the powder degradation and its impact on the reusability of 17-4 PH stainless steel powder are evaluated for the BJT process. Powder characteristics are analyzed after multiple reuse cycles after different process steps, namely drying, sieving, printing and curing. The influence of reused powder on print quality and green densities is investigated and compared to virgin powder. Furthermore, the effect of inert and reducing atmospheres on the powder reusability during curing is examined.