Affiliation: | 1. Advanced Research for Manufacturing Systems Laboratory, Mechanical and Aerospace Engineering Department, University of California, Davis, Davis, CA, USA;2. IMS Laboratory, Mechanical and Aerospace Engineering Department, University of California, Davis, Davis, CA, USA;3. Precision Manufacturing Center, Mechanical and Aerospace Engineering Department, University of California, Berkeley, Berkeley, CA, USA |
Abstract: | In blown powder directed energy deposition (DED) additive manufacturing powdered metal feedstock is pneumatically conveyed to the meltpool via a nozzle. DED nozzles have been the subject to a growing number of research efforts using computational fluid dynamics (CFD) with multiphase flows to study and optimize powder flow. However, many research papers published to date contain powder – nozzle impact dynamics behavior that is not realistic or not derived from experiments that resemble the powder conveyance process in the DED nozzle being studied. To provide a set of data representative of DED powder flow through a nozzle particle image velocimetry (PIV) experiments were conducted using 316L stainless steel metal powder and flat targets with varying surface roughness made of oxygen free copper, mild steel, P20 tool steel, 316L stainless steel, Inconel 718, and Ti-Al6-V4. Normal coefficients of restitution (COR) were calculated and compared to several analytical and empirical models in literature. |