About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Additive Manufacturing: Development of Powders
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| Presentation Title |
Evolution of Powder-Binder Interactions During Reuse of Solid-State Machined Copper Powder in Binder Jet Printing and Their Impact on Microstructure and Mechanical Properties |
| Author(s) |
Mahsa Beyk Khorasani, John Barnes, Markus Chmielus |
| On-Site Speaker (Planned) |
Mahsa Beyk Khorasani |
| Abstract Scope |
Solid-state machining represents an energy-efficient alternative to conventional atomization for producing metal powders. This study leverages machined copper powder, a novel feedstock for AM, to investigate the effects of repeated powder reuse on particle surface chemistry and the consequences for dimensional stability and microstructural evolution. Virgin powder (C0T) is compared with material subjected to five consecutive cure-reuse cycles under identical printing conditions. Oxidation-induced surface chemistry changes increased particle hydrophilicity, promoting binder spreading and causing bleeding and geometric distortion. Minor shifts in particle size distribution and improved apparent density and flowability were observed after the first reuse cycle. Quantitative wetting measurements revealed binder imbibition time decreased from 0.4 s (C0T) to 0.3 s (C5T), while contact angle dropped from 116° to 96°. Sintered density decreased ~7% from C0T to C5T, with microstructures evolving toward larger, irregular, interconnected interlayer pores. Hardness declined progressively, with peak values consistently measured along the build direction. |