A5048497650- High Entropy Alloys Studies
- Additive Manufacturing Materials and Processes
- High-Temperature Coating Behaviors
- Nanoporous metals and alloys
- Additive Manufacturing and 3D Printing Technologies
- Advanced Materials Characterization Techniques
- Welding Techniques and Residual Stresses
- Laser Material Processing Techniques
- Electrocatalysts for Energy Conversion
- CO2 Reduction Techniques and Catalysts
- Block Copolymer Self-Assembly
- Phase-change materials and chalcogenides
- Heusler alloys: electronic and magnetic properties
- Pickering emulsions and particle stabilization
- Advanced Thermoelectric Materials and Devices
- Metal and Thin Film Mechanics
- Advanced materials and composites
- Metallic Glasses and Amorphous Alloys
- Cellular and Composite Structures
- Anodic Oxide Films and Nanostructures
- 2D Materials and Applications
- Supercapacitor Materials and Fabrication
- Nanomaterials for catalytic reactions
University of Massachusetts Amherst
2019-2024
University of California, Santa Barbara
2017
Abstract Laser powder-bed fusion (L-PBF) additive manufacturing presents ample opportunities to produce net-shape parts. The complex laser-powder interactions result in high cooling rates that often lead unique microstructures and excellent mechanical properties. Refractory high-entropy alloys show great potential for high-temperature applications but are notoriously difficult process by processes due their sensitivity cracking defects, such as un-melted powders keyholes. Here, we present a...
Abstract The far-from-equilibrium solidification during additive manufacturing often creates large residual stresses that induce solid-state cracking. Here we present a strategy to suppress cracking in an additively manufactured AlCrFe 2 Ni high-entropy alloy via engineering phase transformation pathway. We investigate the microstructures formed laser powder-bed fusion and directed energy deposition, encompassing broad range of cooling rates. At high rates (10 4 −10 6 K/s), observe...
Printing defects are known to degrade the performance of additively manufactured (AM) alloys. Thus, a thorough understanding their formation mechanisms and effects on mechanical properties AM materials is critically needed. Here, we take CoCrFeNi high-entropy alloy as model material print this by laser powder bed fusion over wide range printing conditions. We reveal processing windows for different including lack (LOF), keyhole, solidification cracking. LOF keyholes can be well correlated...
Heusler compounds XY 2 Z with 24 valence electrons per formula unit are potential thermoelectric materials, given their thermal and chemical stability relatively earth-abundant constituent elements. We present results on the 24-electron compound TiFe2Sn here. First principles calculations this suggest semiconducting behavior. A flat conduction band that could be associated a high Seebeck coefficient upon electron doping is found. series of have been prepared characterized using combination...
Abstract Nanostructured multi-principal element alloys (MPEAs) have been explored as next-generation engineering materials due to unique mechanical and functional properties which significant advantages over traditional dilute alloys. However, the practical applications of nanostructured MPEAs are still limited lack scalable processing approaches prepare a large quantity MPEAs, well an efficient pathway for high-throughput discovery better within their vast compositional space. Here we...
While most research efforts on CO2-to-CO reduction electrocatalysts focus boosting their selectivity, the rate, directly proportional to current density, is another critical parameter be considered in practical applications. This because mass transport associated with diffusion of reactant/product species becomes a major concern at high rate. Nanostructured Au promising electrocatalyst for its very selectivity. However, density commonly achieved conventional nanostructured relatively low (in...