A5074326013- High-Velocity Impact and Material Behavior
- High-pressure geophysics and materials
- Additive Manufacturing Materials and Processes
- Electrochemical sensors and biosensors
- Nuclear Materials and Properties
- Metal and Thin Film Mechanics
- Energetic Materials and Combustion
- Cellular and Composite Structures
- Diamond and Carbon-based Materials Research
- Neuroscience and Neural Engineering
- Laser-Plasma Interactions and Diagnostics
- Advanced materials and composites
- High-Temperature Coating Behaviors
- Polymer composites and self-healing
- Electrochemical Analysis and Applications
- Additive Manufacturing and 3D Printing Technologies
- Conducting polymers and applications
- Advanced Materials and Mechanics
- Metallurgy and Material Forming
- Polymer Foaming and Composites
- Advanced biosensing and bioanalysis techniques
- Metallurgical Processes and Thermodynamics
- Fusion materials and technologies
- MXene and MAX Phase Materials
- 2D Materials and Applications
Sandia National Laboratories
2020-2024
Sandia National Laboratories California
2019-2022
Los Alamos National Laboratory
2010-2020
University of New Mexico
2006-2013
University of Colorado Boulder
2008
Pulsed power accelerators compress electrical energy in space and time to provide versatile experimental platforms for high density inertial confinement fusion science. The 80-TW “Z” pulsed facility at Sandia National Laboratories is the largest device world today. Z discharges up 22 MJ of stored its capacitor banks into a current pulse that rises 100 ns peaks as 30 MA low-inductance cylindrical targets. Considerable progress has been made over past 15 years use precision scientific tool....
Two dimensional transition metal dichalcogenides (2D TMDs) offer promise as opto-electronic materials due to their direct band gap and reasonably good mobility values. However, most metals form high resistance contacts on semiconducting TMDs such MoS2. The large contact limits the performance of devices. Unlike bulk materials, low cannot be stably achieved in 2D by doping. Here we build our previous work which demonstrated that it is possible achieve electrodes phase transformation. We show...
A rapid prototyping technique of microfluidic devices is presented using adhesive transfer tapes. Lab on a chip systems can integrate multiple functions in single platform. Therefore, any should be flexible and robust to accommodate different aspects integrations. In this work, the versatility tapes for applications demonstrated by fabricating wide range Prototypes demonstrating mixing, dielectrophoretic trapping, complex microchannel networks biologically relevant high temperature reactions...
Both shock and shockless compression experiments were performed on laser powder bed fusion (LPBF) Ti–5Al–5V–5Mo–3Cr (Ti-5553) to peak compressive stresses near 15 GPa. Experiments the as-built material, containing a purely β (body centered cubic) microstructure, two differing heat treatments resulting in dual phase α (hexagonal close packed) microstructure. The Hugoniot, Hugoniot elastic limit (HEL), spallation strength measured compared wrought Ti-6Al-4V (Ti-64). results indicate LPBF...
Additive manufacturing (AM) is an attractive approach for the design and fabrication of structures capable achieving controlled mechanical response underlying deformation mechanisms. While there are numerous examples illustrating how quasi-static responses polymer foams have been tailored by additive manufacturing, limited understanding these materials under shockwave compression. Dynamic compression experiments coupled with time-resolved X-ray imaging were performed to obtain insights into...
Cellular silicone reinforced with silica filler prepared using additive manufacturing (AM) have been used widely for vibrational damping and shockwave mitigation. The two most commonly printed cellular structures, simple cubic (SC) face-centered tetragonal (FCT) display distinctly different static dynamic mechanical responses dependent upon structure. In this work, the relationship between size composition response is investigated polydimethylsiloxane-based silicones filled aluminum oxide,...
The advent of additive manufacturing (AM) has enabled topological control structures at the micrometer scale, transforming properties polymers for a variety applications. Examples include tailored mechanical responses, acoustic properties, and thermal properties. Porous polymer materials are class used shock blast mitigation, yet they frequently possess lack structural order largely developed evaluated via trial-and-error. Here, we demonstrate shockwave dissipation through...
The effect of microstructure on the high-rate tensile failure additively manufactured (AM) 304L stainless steel is analyzed. method uses state-based peridynamics with a new model for time dependence within grains. incorporates anisotropy in elastic and plastic response grain shapes lattice orientations are initialized directly from electron backscatter diffraction (EBSD) images. results compared to test data plate impact experiments over range velocities. A set parameters homogenized...
This research reports on the physical and mechanical effects of various filler materials used in direct ink write (DIW) 3-D printing resins. The data reported herein supports interpretation discussion provided article "Impact Filler Composition Mechanical Dynamic Response Printed Silicone-based Nanocomposite Elastomers" [1]. datasheet describes model structures interaction energies between fillers other components by using Molecular Dynamics (MD) simulations. report includes responses...
Time-resolved x-ray diffraction (XRD) was used to examine the behavior of Ce under shock loading stress states up 22 GPa that span shock-melt transition. Experiments reported here observed held at a steady state for ∼500 ns prior being uniaxially released ambient pressure. XRD shows constant pattern over duration with rapid solidification occurring on release. Cerium found remain crystalline as Poisson's ratio (ν) increases in α-phase incipient melt once ν reaches 0.5. Diffraction results...
Control of structural topology, via a bottom-up approach, is now possible through the advent and continuing maturation additive manufacturing techniques. For example, new classes porous materials with increased strength-to-density ratios, novel thermal acoustic properties, even "metamaterial" properties such as negative Poisson ratios have been recently realized by tailoring deformation mechanisms instabilities. It control organizing features at mesoscale (100s nm- μm's) that has led to...
Additive manufacturing (AM) has shifted the industrial paradigm enabling topologically optimized lattice architectures for lightweight structural components that provide superior mechanical properties and energy absorption capabilities. Despite these key advantages, property-to-performance relationship of AM at high strain rates have not been experimentally characterized, therefore limiting development mesoscale modeling techniques to further understand constitutive response metallic...
Recent advancements in coupling dynamic loading platforms with third generation light sources are providing new means to study materials at extreme conditions. Diagnostics such as X-ray diffraction (XRD) and phase contrast imaging (PCI) being employed in-line for studying phenomena transitions, microstructural evolution, etc. Here we the well-known polymorphic transformation (α- ε phase) polycrystalline iron through front-surface plate impact experiments using techniques Dynamic Compression...
We have developed a novel platform comprising 3-D micropillar sensor array that can be encapsulated with high-k dielectric material for applications in capacitive neural sensing. The present device incorporates over 3800 electrodes, grouped into 60 independent clusters (for compatibility existing electronics), spread an area of 750 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . Each cluster site consists 8 × micropillars,...