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Full-Text Articles in Manufacturing
Development Of In-Situ Radiometric Inspection Methods For Quality Assurance In Laser Powder Bed Fusion, Cody S. Lough
Development Of In-Situ Radiometric Inspection Methods For Quality Assurance In Laser Powder Bed Fusion, Cody S. Lough
Doctoral Dissertations
“Laser Powder Bed Fusion (LPBF) metal Additive Manufacturing (AM) fabricates 3D metal parts layer-by-layer. The process enables production of geometrically complex parts that are difficult to inspect with traditional methods. The LPBF parts experience significant geometry driven thermal variations during manufacturing. This creates microstructure and mechanical property inhomogeneities and can stochastically cause defects. Mission critical applications require part qualification by measuring the defects non-destructively. The layer-to-layer nature of LPBF permits non-intrusive measurement of radiometric signals for a part’s entire volume. These measurements provide thermal features that correlate with the local part health. This research establishes Optical Emission Spectroscopy (OES) and …
Fabrication Of Silicon Nitride Parts By Ceramic On-Demand Extrusion Process, Sachin Choudhary
Fabrication Of Silicon Nitride Parts By Ceramic On-Demand Extrusion Process, Sachin Choudhary
Masters Theses
“Ceramic On-Demand Extrusion (CODE) is a patented solid freeform fabrication method for manufacturing high-density monolithic ceramic parts. In the past 5-6 years, the technology has been successfully implemented to fabricate alumina and zirconia parts. The mechanical characterizations also show CODE’s high potential in achieving desired structural properties. The present study covers the fabrication of silicon nitride parts by CODE process, which entailed the design of paste formulation for achieving rheology suitable for dimensional control in fabricated parts and determining firing temperature and the content of sintering additives for silicon nitride green bodies fabricated by CODE. The density, hardness, and fracture …
Research And Development Of A Laser Hot Wire Deposition Process, Christopher Croft
Research And Development Of A Laser Hot Wire Deposition Process, Christopher Croft
Masters Theses
“Laser hot wire directed energy deposition (DED) is an increasingly popular method for improving deposition rates and overall reduction of build times in DED processing. While there is clear benefit, it is important to fully understand the impact of preheating the wire. This work focuses on developing a model that describes bead geometry output using all factors including the wire preheat. The model was fit with over 150 data points that explored a large range of each factor. The resulting model was then leveraged to evaluate a process control variable. The technique chosen used feedback from the hot wire system …