Publications

Jan, 2024

Conference Paper

Correlations of Interlayer Time with Distortion of Large Ti-6Al-4V Components in Laser Metal Deposition with Wire

Laser metal deposition with wire (LMD-w) is one of the emerging additive manufacturing (AM) technologies for large-scale aerospace components due to high deposition rates and material efficiency. However, it often results in undesired stresses and distortions due to non-uniform expansion and contraction of material during the printing. Controlling of inter-layer time, preh…

Dec, 2023

Journal

Influence of Geometry on Columnar to Equiaxed Transition during Electron Beam Powder Bed Fusion of IN718

Correlation between spot-melt scan parameters (linear spot-density aka areal energy density), build geometry, and solidification microstructure evolution (columnar vs equiaxed) in a powder bed fusion technology is investigated. It is shown that to maintain the equiaxed solidification microstructure evolution in electron beam powder bed additive manufacturing (AM), the area…

Dec, 2023

Conference Paper

Performance and Feature Improvements in Parareal-based Power System Dynamic Simulation

In recent years, a novel Parareal-based approach has been developed for fast transient simulations of large power system interconnections. Parareal belongs to the class of Parallel-in-time algorithms for solution of systems of differential-algebraic equations in parallel over an interval of time. The selection of a reasonably fast and accurate coarse solution is crucial to…

Dec, 2023

ORNL Report

Implementation of Disruptive Designs for Gas Turbine Components Utilizing Additive Manufacturing

Dec, 2023

Journal

Prediction of residual strain/stress validated with neutron diffraction method for wire-feed hybrid additive/subtractive manufacturing

Hybrid manufacturing integrates additive manufacturing (AM) and subtractive manufacturing in the same machine. The integration of the two processes enables the creation of complex geometry, further reduces material waste, and decreases lead time. Moreover, this in-envelop method enables an interleaved printing strategy in which the part is partially AM printed and then mac…

Nov, 2023

Journal

Fragmentation of Copper Current Collectors of Li-ion Batteries Post Spherical Indentation

Large, areal, brittle fracture of copper current collector foils was observed by 3D x-ray computed tomography (XCT) of a spherically indented Li-ion cell. This fracture was hidden and non-catastrophic to a degree because the graphite layers deformed plastically, and held the materials together so that the cracks in the foils could not be seen under optical and electron mic…

Nov, 2023

Journal

Localized melt-scan strategy for site specific control of grain size and primary dendrite arm spacing in electron beam additive manufacturing

Nov, 2023

Journal

Strain distribution and failure mode of polymer separators for Li-ion batteries under biaxial loading

Deformation of polymer separators for Li-ion batteries has been studied under biaxial tension by using a dome test setup. This deformation mode provides characterization of separator strength under more complex loading conditions, closer representing deformation of an electric vehicle battery during crash event, compared to uniaxial tension or compression. Two polymer sepa…

Nov, 2023

Journal

Limiting Internal Short-Circuit Damage by Electrode Partition for Impact-Tolerant Li-Ion Batteries

We report on a unique safety mechanism introduced to the Li-ion battery design to mitigate the effects of a mechanical impact event by limiting the current moving through resulting internal shorts, thereby preventing thermal runaway. “Slitted” electrodes and current collectors would electrically isolate the impacted parts of the electrodes before puncturing the separator.…

Nov, 2023

ORNL Report

Crashworthiness Models for Automotive Batteries

Nov, 2023

ORNL Report

Virtual Integrated Battery Environment (VIBE): Version 1.2 Release Documentation

Nov, 2023

ORNL Report

Coupled Bison/Thermochimica Simulation of Hydride Formation in Zircalloy Cladding

The report describes implementation of the thermodynamics models for simulation of zirconium hydride formation in LWR fuel cladding. The current models for ZrHx formation are based on empirical rate models that must calibrated to materials and regimes of interest. The thermodynamic approach enables hydride formation calculations based on fundamental thermodynamics principl…