• Carbide Nanoparticle Dispersion Techniques for Metal Powder Metallurgy 

  Rocky, Bahrum Prang; Weinberger, Christopher R.; Daniewicz, Steven R.; Thompson, Gregory B. (2021)

  Nanoparticles (NP) embedded into a matrix material have been shown to improve mechanical properties such as strength, hardness, and wear-resistance. However, the tendency of NPs to agglomerate in the powder mixing process ...
• Composition-Dependent Apparent Activation-Energy and Sluggish Grain-Growth in High Entropy Alloys 

  Gwalani, B.; Salloom, R.; Alam, T.; Valentin, S. G.; Zhou, X.; Thompson, G.; Srinivasan, S. G.; Banerjee, R. (2019)

  Experimental results reveal that the apparent activation-energy for grain-growth in an fcc-based AlxCoCrFeNi high entropy alloy (HEA) system increases from 179 to 486 kJ/mol when the Al content increases from x = 0.1 to ...
• A Computational Investigation into the Microstructures and Stability of the Zeta Phase in Transition Metal Carbides and Nitrides 

  Weinberger, Christopher R.; Yu, Hang; Wang, Billie; Thompson, Gregory B. (2018)

  A high-volume fraction of the zeta phase in multiphase group VB transition metal tantalum carbides has been shown to dramatically increase fracture toughness. This has been attributed to its unique nanoscale lath-based ...
• Chemical Variation Induced Nanoscale Spatial Heterogeneity in Metallic Glasses 

  Wang, Neng; Ding, Jun; Luo, Peng; Liu, Yanhui; Li, Lin; Yan, Feng (2018)

  Metallic glasses possess amorphous structures with inherent heterogeneity at the nanoscale. A combined experimental and modeling investigation to elucidate the chemical effect on such nanoscale heterogeneity in a Cu-Zr-Al ...
• Wetting of Al2O3 by Molten Aluminum: The Influence of BaSO4 Additions 

  Aquilar-Santillan, Joaquin (2008)

  The effects of BaSO4 additions on the wetting of alumina by molten aluminum were studied by the sessile drop technique. To study the effect of BaSO4 decomposition (1100–1150◦ C), the additions were treated at two temperatures ...
• Plasticity Mechanisms in HfN at Elevated and Room Temperature 

  Vinson, Katherine; Yu, Xiao-Xiang; De Leon, Nicholas; Weinberger, Christopher R.; Thompson, Gregory B. (2016-10-06)

  HfN specimens deformed via four-point bend tests at room temperature and at 2300 °C (~0.7 Tm) showed increased plasticity response with temperature. Dynamic diffraction via transmission electron microscopy (TEM) revealed ...
• Influence of Grain Boundary Character and Annealing Time on Segregation in Commercially Pure Nickel 

  Welsh, Shery L.; Kapoor, Monica; Underwood, Olivia D.; Martens, Richard L.; Thompson, Gregory B.; Evans, Jeffrey L. (2016)

  Commercially pure nickel (Ni) was thermomechanically processed to promote an increase in Σ3 special grain boundaries. Engineering the character and chemistry of Σ3 grain boundaries in polycrystalline materials can help in ...
• Grain Boundary Specific Segregation in Nanocrystalline Fe(Cr) 

  Zhou, Xuyang; Yu, Xiao-xiang; Kaub, Tyler; Martens, Richard L.; Thompson, Gregory B. (2016-10-06)

  A cross-correlative precession electron diffraction – atom probe tomography investigation of Cr segregation in a Fe(Cr) nanocrystalline alloy was undertaken. Solute segregation was found to be dependent on grain boundary ...
• Lattice Expansion in Nanocrystalline Niobium Thin Films 

  Banerjee, R.; Sperling, E. A.; Thompson, G. B.; Fraser, H. L.; Bose, S.; Ayyub, P. (2003-04-09)

  High-purity nanocrystalline niobium (Nb) thin films have been deposited using high-pressure magnetron sputter deposition. Increasing the pressure of the sputtering gas during deposition has systematically led to reduced ...
• Tuning Phase Stability in Nanocomposite Multilayers 

  Thompson, G. B.; Banerjee, R.; Fraser, H. L. (2003-08-26)

  As thin-film layers in a multilayered stack are reduced in thickness, changes in phase stability can result within the individual layers. These changes in phase are expected to have a significant influence upon the functional ...
• Predicting Pseudomorphic Phases in Multilayers: Hexagonal-Closed-Packed Nb in Nb/Zr 

  Thompson, G. B.; Banerjee, R.; Fraser, H. L. (2003-12-17)

  As the dimensions of materials are reduced to the nanometer scale, changes in phase stability, referred to as pseudomorphism, are being reported. Such changes in phase stability are often serendipitously discovered in ...
• Sintering Behavior of Spin-Coated FePt and FePtAu Nanoparticles 

  Kang, Shishou; Jia, Zhiyong; Zoto, I.; Reed, D.; Nikles, David E.; Harrell, J. W. (2006-04-19)

  ePt and [FePt]95Au5 nanoparticles with an average size of about 4nm were chemically synthesized and spin coated onto silicon substrates. Samples were subsequently thermally annealed at temperatures ranging from 250 to 500°C ...
• Size Effect Ordering in [FePt]100-xCrx Nanoparticles 

  Thompson, G. B.; Srivastava, C.; Harrell, J. W.; Nikles, D. E. (2006-03-02)

  A series of [FePt]100−xCrx nanoparticles (x=5, 10, and 16at.%) was chemically synthesized by two different techniques. In one method, the simultaneous chemical reduction of FeCl2∙4H2O, Pt-acetylacetonate, and Cr-acetylacetonate ...
• In Situ Transmission Electron Microscopy of Ion Irradiated Fe-Pt Alloy Thin Films 

  Thompson, G. B.; Morgan, N. W.; Birtcher, R. C. (2006-12-21)

  We report the microstructural evolution during irradiation of FePt and FePt 25at.% thin films sputter deposited onto electron transparent silicon monoxide substrates. The films were studied in situ for 500keV Kr+ irradiation ...
• Microstructures and Magnetic Alignment of L10 FePt Nanoparticles 

  Kang, Shishou; Shi, Shifan; Jia, Zhiyong; Thompson, G. B.; Nikles, David. E.; Harrell, J. W. (2007-05-09)

  Chemically ordered FePt nanoparticles were obtained by high temperature annealing a mixture of FePt particles with NaCl. After the NaCl was removed with de-ionized water, the transformed FePt nanoparticles were redispersed ...
• Formation of FePt Nanoparticles by Organometallic Synthesis 

  Bagaria, H. G.; Johnson, D. T.; Srivastava, C.; Thompson, G. B.; Shamsuzzoha, M.; Nikles, D. E. (2007-05-23)

  Our interest in determining the mechanism of FePt nanoparticle formation has led to this study of the evolution of particle size and composition during synthesis. FePt nanoparticles were prepared by the simultaneous reduction ...
• Selective Area Synthesis of Magnesium Oxide Nanowires 

  Kim, G.; Martens, R. L.; Thompson, G. B.; Kim, B. C.; Gupta, A. (2007-11-28)

  Single crystalline magnesium oxide MgO nanowires exhibiting a square cross section have been grown on 001-oriented MgO and Si substrates using the vapor-liquid-solid growth mechanism. While the nanowires grow vertically ...
• Formation Mechanism and Composition Distribution of FePt Nanoparticles 

  Srivastava, Chandan; Balasubramanian, Jayendra; Turner, C. Heath; Wiest, John M.; Bagaria, Hitesh G.; Thompson, Gregory B. (2007-11-27)

  Self-assembled FePt nanoparticle arrays are candidate structures for ultrahigh density magnetic storage media. One of the factors limiting their application to this technology is particle-to-particle compositional variation. ...
• Compositional Evolution During the Synthesis of FePt Nanoparticles 

  Thompson, G. B.; Srivastava, Chandan; Nikles, David E. (2008-09-25)

  A series of FePt nanoparticles was synthesized by the thermal decomposition of iron pentacarbonyl and reduction in platinum acetylacetonate in phenyl ether solvent. A range of precursor molar ratios of 2, 1.5, and 1 ...
• Compositional Dependent Thin Film Stress States 

  Thompson, G. B.; Fu, B. (2010-08-23)

  This paper addresses in situ stress evolution of two-component FexPt1−x, where x spanned 0 to 1, alloy thin films. The stresses of the high-temperature, quenched-in, solid solution phase was determined by in situ wafer ...

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