A5076627740- Intermetallics and Advanced Alloy Properties
- Rare-earth and actinide compounds
- Metal and Thin Film Mechanics
- High Temperature Alloys and Creep
- Metallurgical and Alloy Processes
- Microstructure and mechanical properties
- Magnetic and transport properties of perovskites and related materials
- Boron and Carbon Nanomaterials Research
- High-pressure geophysics and materials
- Magnesium Alloys: Properties and Applications
- Aluminum Alloys Composites Properties
- Thermal Expansion and Ionic Conductivity
- MXene and MAX Phase Materials
- Thermodynamic and Structural Properties of Metals and Alloys
- Aluminum Alloy Microstructure Properties
- Nuclear Materials and Properties
- Advanced Materials Characterization Techniques
- Advanced Condensed Matter Physics
- Microstructure and Mechanical Properties of Steels
- Titanium Alloys Microstructure and Properties
- High Entropy Alloys Studies
- Semiconductor materials and interfaces
- Additive Manufacturing Materials and Processes
- Electronic and Structural Properties of Oxides
- X-ray Diffraction in Crystallography
Pennsylvania State University
2016-2025
National Energy Technology Laboratory
2014-2024
Peking University
2024
Qufu Normal University
2024
Cornell University
2017-2021
Interface (United States)
2021
United States Air Force Research Laboratory
2021
Leibniz Institute for Crystal Growth
2017
The University of Tokyo
2017
Indian Institute of Technology Kanpur
2017
We propose a mixed-space approach using the accurate force constants calculated by direct in real space and dipole–dipole interactions linear response theory reciprocal space, making prediction of phonon frequencies for polar materials possible as well theory. As examples, present approach, we predict first-principles properties α-Al2O3, MgO, c-SiC, h-BN, which are excellent agreement with available experimental data.
A Na-ion solid-state electrolyte, Na3P0.62As0.38S4, is developed with an exceptionally high conductivity of 1.46 mS cm–1 at 25 °C and enhanced moisture stability. Dual effects alloying element As (lattice expansion a weaker AsS bond strength) are responsible for the superior conductivity. Improved stability regulated by shifting low-energy reactions to high-energy ones due As.
Abstract Although the peak power density of anion exchange membrane fuel cells (AEMFCs) has been raised from ≈0.1 to ≈1.4 W cm −2 over last decade, a majority AEMFCs reported in literature have not demonstrated achieve consistently high performance and steady‐state operation. Poly(olefin)‐based AEMs with fluorine substitution on aromatic comonomer show considerably higher dimensional stability compared samples that do contain fluorine. More importantly, fluorinated poly(olefin)‐based exhibit...
Using an efficient strain-stress method, the first-principles elastic constants cij’s of α-Al2O3 and θ-Al2O3 have been predicted within local density approximation generalized gradient approximation. It is indicated that more accurate calculations can be accomplished by The provide helpful guidance for future measurements, especially negative c15. present results make stress estimation in thermally grown oxides containing α- possible, which turn insights preventing failure thermal barrier...
A first-principles approach to calculating the elastic stiffness coefficients at finite temperatures was proposed. It is based on assumption that temperature dependence of mainly results from volume change as a function temperature; it combines calculations constants 0 K and phonon theory thermal expansion. Its applications Al, Cu, Ni, Mo, Ta, NiAl, Ni₃Al up their respective melting points show excellent agreement between predicted values existing experimental measurements.
A systematic study of stacking fault energy (γSF) resulting from induced alias shear deformation has been performed by means first-principles calculations for dilute Ni-base superalloys (Ni23X and Ni71X) various alloying elements (X) as a function temperature. Twenty-six are considered, i.e., Al, Co, Cr, Cu, Fe, Hf, Ir, Mn, Mo, Nb, Os, Pd, Pt, Re, Rh, Ru, Sc, Si, Ta, Tc, Ti, V, W, Y, Zn, Zr. The temperature dependence γSF is computed using the proposed quasistatic approach based on predicted...
Epitaxial La-doped BaSnO3 films were grown in an adsorption-controlled regime by molecular-beam epitaxy, where the excess volatile SnOx desorbs from film surface. A on a (001) DyScO3 substrate exhibited mobility of 183 cm2 V−1 s−1 at room temperature and 400 10 K despite high concentration (1.2 × 1011 cm−2) threading dislocations present. In comparison to other reports, we observe much lower (BaO)2 Ruddlesden-Popper crystallographic shear faults. This suggests that addition dislocations,...
Abstract Although the theory of lattice dynamics was established six decades ago, its accurate implementation for polar solids using direct (or supercell, small displacement, frozen phonon) approach within framework density-function-theory-based first-principles calculations had been a challenge until recently. It arises from fact that vibration-induced polarization breaks periodicity, whereas periodic boundary conditions are required by typical calculations, leading to an artificial...
Unprecedented interest has been spurred recently in two-dimensional (2D) layered transition metal dichalcogenides (TMDs) that possess tunable electronic and optical properties. However, synthesis of a wafer-scale TMD thin film with controlled layers homogeneity remains highly challenging due mainly to the lack thermodynamic diffusion knowledge, which can be used understand design process conditions, but falls far behind rapidly growing field. Here, an integrated density functional theory...
Variations of energy, stress, and magnetic moment fcc Ni as a response to shear deformation the associated ideal strength (τIS), intrinsic (γSF) unstable (γUS) stacking fault energies have been studied in terms first-principles calculations under both alias affine regimes within {111} slip plane along directions. It is found that (i) energy γSF nearly independent used, albeit slightly smaller value predicted by pure (with relaxation) compared one from simple (without relaxation); (ii)...
The growth, deformation, and extrinsic faults in binary Mg–X alloys are investigated via first-principles calculations. Here, the alloying elements X include Al, Ca, Cu, Fe, K, La, Li, Mn, Na, Nd, Pr, Si, Sn, Sr, Y, Zn, Zr. In addition to stacking fault energies, effect of on bond structure Mg studied term electron localization morphology. It is observed that rod-like directional bonds non-fault planes transform into tetrahedral morphologies strengthened by Zn but weakened Na.
Abstract Refractory high-entropy alloys present attractive mechanical properties, i.e., high yield strength and fracture toughness, making them potential candidates for structural applications. Understandings of atomic electronic interactions are important to reveal the origins formation their structure−dominated thus enabling development a predictive approach rapidly designing advanced materials. Here, we report basis valence−electron-concentration-categorized principles observed serration...