Explanipedia

Non-circular electron beam spot welds in stainless steel alloys Open

J. W. Elmer, Gordon R. Gibbs · 2025

Circularly symmetric-shaped spot welds are desirable for welding applications as they relate to heat and fluid flow conditions in the melt pool with predictable weld penetrations and repeatable results. Non-circular spot welds on the other…

The effect of filament peaking on electron beam weld quality Open

J. W. Elmer, Gordon R. Gibbs · 2025

Electron beam welding uses high intensity beams that are generated by an electron emitting cathode under high vacuum conditions. The cathode, typically a ribbon or wire filament of refractory metal, must be heated to sufficiently high temp…

Induction melting, casting, and weldability of a group IAB iron meteorite Open

J. W. Elmer, J.S. Bellino · 2025

Future construction of large-scale space structures will need to exploit natural space resources for raw materials such as iron from asteroids, which is expected to be a key element due to its availability in near-Earth objects. Although t…

UHTC-TPMS Heat Exchangers for Concentrating Solar Power Applications with Thermal Energy Storage in Molten Chlorides Open

Stephen S. Raiman, M. Ross, J. W. Elmer, J. M. Kelly, M. Ross , et al. · 2024

Metals beyond tomorrow: Balancing supply, demand, sustainability, substitution, and innovations Open

T. DebRoy, J. W. Elmer · 2024

Modeling Second-Phase Formation during Rapid Resolidification of Stainless Steel Alloys Open

J. W. Elmer, Thomas W. Eagar, Samuel M. Allen · 2024

Many common stainless steel (SS) alloy microstructures consist of a mixture offerrite and austenite phases, however, when these alloys are rapidly resolidified using laser beam (LB) or electron beam (EB) processes they solidify in the sing…

EBSD quantification of delta ferrite in austenitic stainless steel welds Open

C.T. Necker, J. Milewski, J. W. Elmer · 2024

Power Density Distributions in Electron Beams Open

J. W. Elmer, Alan T. Teruya, Gordon R. Gibbs · 2023

Measuring and controlling the power density distribution of electron beams used for welding is critical for producing repeatable welds and for transferring welding parameters between different machines. On any given machine, the power dens…

Resonant Ultrasonic Spectroscopy: A Modal-Analysis Approach for Additive Manufacturing Open

J. V. Candy, Karl A. Fisher, J. W. Elmer · 2023

Resonant ultrasonic spectroscopy is a methodology capable of measuring a change in modal resonant frequencies of material structures. It encompasses an inversion technique based on the eigen-frequencies of a simple regular sample geometry …

The effect of sulfur content on weld penetration in austenitic stainless steel orbital tube welds Open

J. W. Elmer, Gordon R. Gibbs · 2023

Concentric semi-circular split profiling for computed tomographic imaging of electronic beams Open

J. W. Elmer, Alan T. Teruya · 2023

Apparatus and method for analyzing an electron beam including a circular sensor disk adapted to receive the electron beam, an inner semi-circular slit in the circular sensor disk; an outer semi-circular slit in the circular sensor disk whe…

Astigmatic electron beam propagation Open

J. W. Elmer, Gordon R. Gibbs · 2023

An astigmatic electron beam with an ellipticity ratio of approximately 2:1 was examined using the Enhanced Modified Faraday Cup (EMFC) diagnostic to measure its properties and show how the power density distribution varies near the beam wa…

Si-based CTE-matched substrate for laser diode packaging Open

Susant K. Patra, R. J. Deri, J. W. Elmer · 2023

A Cu—Si—Cu substrate having a silicon substrate, copper plating on opposite sides of the silicon substrate, and copper vias extending thru the silicon substrate to electrically and thermally connect the copper platings together. The thickn…

CTE-tuned pyrolytic graphite (PG) substrate to minimize joining stress between laser diode and the substrate Open

Susant K. Patra, R. J. Deri, J. W. Elmer · 2023

A pyrolytic graphite (PG) substrate and laser diode package includes a substrate body having a PG crystalline structure with a basal plane oriented at a pre-determined orientation angle as measured from a longitudinal axis of a heat genera…

Manifold free multiple sheet superplastic forming Open

J. W. Elmer, Robert L. Bridges · 2023

Fluid-forming compositions in a container attached to enclosed adjacent sheets are heated to relatively high temperatures to generate fluids (gases) that effect inflation of the sheets. Fluid rates to the enclosed space between the sheets …

High flux diode packaging using passive microscale liquid-vapor phase change Open

Todd M. Bandhauer, R. J. Deri, J. W. Elmer, Jack Kotovsky, Susant K. Patra · 2023

A laser diode package includes a heat pipe having a fluid chamber enclosed in part by a heat exchange wall for containing a fluid. Wicking channels in the fluid chamber is adapted to wick a liquid phase of the fluid from a condensing secti…

Modified Faraday cup Open

J. W. Elmer, Alan T. Teruya, Dennis O’Brien · 2023

A tomographic technique for measuring the current density distribution in electron beams using electron beam profile data acquired from a modified Faraday cup to create an image of the current density in high and low power beams. The modif…

Electron beam diagnostic system using computed tomography and an annular sensor Open

J. W. Elmer, Alan T. Teruya · 2023

A system for analyzing an electron beam including a circular electron beam diagnostic sensor adapted to receive the electron beam, the circular electron beam diagnostic sensor having a central axis; an annular sensor structure operatively …

Angled slit design for computed tomographic imaging of electron beams Open

J. W. Elmer, Alan T. Teruya · 2023

Computed tomographic method and apparatus includes an electron or ion beam having a beam axis, a refractory metal disk; at least one slit in the refractory metal disk that receive the beam, wherein the slit is at an angle to the beam axis;…

Vacuum manufacture of cryogenic pressure vessels for hydrogen storage Open

Salvador M. Aceves, J. W. Elmer, Francisco Espinosa-Loza, Guillaume Petitpas, J. L. Smith , et al. · 2023

In one aspect the present disclosure relates to a method of manufacturing a cryogenic pressure vessel. The method may include providing a metal lined, composite wrapped vessel which has a boss. The method may further include securing an in…

Reduced pressure laser weld comparison to electron beam welds in Ti-6Al-4 V Open

J. W. Elmer, JAY VAJA, Gordon R. Gibbs · 2022

Reduced pressure laser welds were made using a 6-kW commercial fiber-laser system on Ti-6Al-4 V and compared to electron beam welds of the same beam diameters as measured by beam diagnostics. The laser welds showed keyhole characteristics …

Processing of Ultrasonic Measurements for an Additive Manufacturing Application Open

J. V. Candy, Kenneth A. Fisher, J. W. Elmer · 2022

Resonant ultrasonic spectroscopy is an effective methodology capable of measuring a change in modal resonant frequencies of material structures. It encompasses techniques based on ultrasonic frequencies employed to estimate elastic coeffic…

Post-build thermomechanical processing of wire arc additively manufactured stainless steel for improved mechanical properties and reduction of crystallographic texture Open

J. W. Elmer, Karl A. Fisher, Gordon R. Gibbs, John Sengthay, D. S. Urabe · 2021

Mechanical rolling and annealing of wire-arc additively manufactured stainless steel plates Open

J. W. Elmer, Gordon R. Gibbs · 2021

Thin walls of 304L stainless steel were fabricated by wire-arc additive manufacturing (WAAM) followed by post-build thermomechanical processing to modify the as-built microstructure and properties. The walls were made using a high-depositi…

High Resolution and Fast Throughput-time X-ray CT for Semiconductor Packaging Applications Open

Y Li, M Pacheco, Deepak Goyal, J. W. Elmer, Holly D. Barth , et al. · 2021

Direct Observation of Phase Transformations in Austenitic Stainless Steel Welds Using In-situ Spatially Resolved and Time-resolved X-ray Diffraction Open

J. W. Elmer, Joe Wong, Thorsten Ressler · 2021

Spatially resolved x-ray diffraction (SRXRD) and time resolved x-ray diffraction (TRXRD) were used to investigate real time solid state phase transformations and solidification in AISI type 304 stainless steel gas tungsten arc (GTA) welds.…

Characterization of Electron Beams in Multiple Welders Using the Enhanced Modified Faraday Cup Open

Todd Palmer, J. W. Elmer · 2021

Using the Enhanced Modified Faraday Cup (EMFC), the differences in the beams produced by two electron beam (EB) welders are characterized at different focus settings and work distances. For example, EMFC measurements show that sharply focu…

Some Physics Fundamentals of High Energy Density Welding Open

P. Burgardt, J. W. Elmer, Patrick W Hochanadel, Douglas D. Kautz · 2021

The purpose of this section of this document is to provide a brief summary of the physics aspects of high energy density welding (HEDW). One reason for this is to help elucidate some of the differences between EBW and LBW. A fundamental un…

Directed energy deposition additive manufacturing of functionally graded Al-W composites Open

James Kelly, J. W. Elmer, Frederick J. Ryerson, J.R.I. Lee, J Haslam · 2021

Wire-Based Additive Manufacturing of Stainless Steel Components Open

J. W. Elmer, Gordon R. Gibbs, John S. Carpenter, D.R. Coughlin, Pat W Hochanadel , et al. · 2020

Three different wire-fed additive manufacturing (AM) processes were employed to evaluate differences between laser, arc, and electron beam heat sources used for high-deposition-rate AM on the order of 1 kg/h. Optimum weld and build paramet…

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