Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Engineering
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 …
Hydrokinetic Turbine Composite Blades And Sandwich Structures: Damage Evaluation And Numerical Simulation, Mokhtar Fal
Hydrokinetic Turbine Composite Blades And Sandwich Structures: Damage Evaluation And Numerical Simulation, Mokhtar Fal
Doctoral Dissertations
“Composite materials are gaining interest due to their high strength to weight ratio. This study deals with both experimental and numerical approaches to cover the aspects of the failure of composite materials in hydrokinetic turbine applications. In Part I, the location and magnitude of failure in the horizontal axis water turbine carbon fiber-reinforced polymer (CFRP) composite blades with different laminate stacking sequences were investigated. Two lay-up orientations were adopted for this work ([0⁰]4 and [0⁰/90⁰]2s). A finite element analysis model was generated to examine the stresses along the blade. Five angles were introduced to study the effect …
Additive Manufacturing Of Customized Lithium-Ion Batteries: Process Fundamentals And Applications, Xiaowei Yu
Additive Manufacturing Of Customized Lithium-Ion Batteries: Process Fundamentals And Applications, Xiaowei Yu
Doctoral Dissertations
“In the pasting decades, considerable efforts have been spent in developing the next-generation lithium-ion batteries (LIBs), from advanced active materials to new manufacturing methods. The development of additive manufacturing (AM) has brought new opportunities to LIBs. In this work, two AM methods are introduced for fabricating electrodes of LIBs. The first method is aerosol printing, which is a solvent-based wet additive method. Whereas the second method is a solvent-free, dry printing method. The commonly used materials for current collectors and active materials (including cathodes and anodes) of LIBs are aerosol printed and the electrochemical functionalities of the printed materials are …
A Framework For A Successful Additive Repair System, Todd E. Sparks
A Framework For A Successful Additive Repair System, Todd E. Sparks
Doctoral Dissertations
“The goal of this research is to generate a revolutionary improvement to the usability and usefulness of additive repair technology by integrating a set of tools into a seamless work flow. Insufficient automation in the current repair process is a huge hurdle in achieving cost-effective, reliable repairs. Many opportunities have been missed due to inconsistency, quality issues and lack of robustness and flexibility. The present work addresses deficiencies in preparatory steps such as 2D and 3D geometry processing, parameter estimation, and path planning as well as on-machine execution of the path plan. The bulk of the effort is focused on …