Determination of Ag/Co Interfacial Free Energies by Biaxial Zero Creep Experiments

2003 ◽  
Vol 778 ◽  
Author(s):  
Bing An ◽  
Tong-jun Zhang ◽  
Chao Yuan ◽  
Kun Cui ◽  
Wei Zhang
Keyword(s):  
Residual Stress ◽  
Plastic Deformation ◽  
Free Energy ◽  
Room Temperature ◽  
Multilayer Films ◽  
Free Energies ◽  
Grain Distribution ◽  
Interfacial Free Energies

AbstractTo measure the Ag/Co interfacial free energies, biaxial zero creep experiments were performed on Ag/Co multilayer films deposited on the Si (111) wafers. As the samples were heated from room temperature to 450°C, the residual stress in films, which was in situ monitored by substrate curvature technique, decayed gradually to zero due to the increasing plastic deformation in films. After held for several hours at 450°C, they reached a zero creep state while the equilibrium stresses were measured. The annealed element layers were immiscible, and exhibited the column grain distribution and (111) preferred orientations. Based on the Josell model, the free energy of Ag/Co (111) interfaces at 450°C was found to be 1.02 ± 0.17 J/m2.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

Studies of Ag/Fe Interfacial Free Energies by Biaxial Zero Creep Experiments

2003 ◽  
Vol 10 (05) ◽  
pp. 763-769 ◽  
Author(s):  
Bing An ◽  
Tong-Jun Zhang ◽  
Chao Yuan ◽  
Kun Cui
Keyword(s):  
Rf Magnetron Sputtering ◽  
Film Stress ◽  
Multilayer Thin Films ◽  
Free Energies ◽  
Stress Monitoring ◽  
Isothermal Process ◽  
Long Duration ◽  
Grain Distribution ◽  
Interface Free Energy ◽  
Interfacial Free Energies

Biaxial zero creep experiments based on the Josell model were performed on Ag/Fe multilayer thin films to determine their interfacial free energies. Various multilayer samples on stiff wafers prepared by RF magnetron sputtering were subjected to annealing of long duration at 550°C, while a substrate curvature technique was employed for real-time film stress monitoring. Sufficient plastic flow in films makes possible a zero creep equilibrium state to present during this isothermal process, and as a result the interfacial free energies in multilayer interfaces are equilibrated with the elastic strain energies arising from the substrate bending. There is no collapse in the annealed multilayer structures. They are still stably layer-built and exhibit a column grain distribution. XRD results show that Ag and Fe layers have (111) and (110) preferred orientations, respectively. In accordance with a revised Josell model, the equilibrium stresses were measured and the Ag (111)/ Fe (110) interface free energy at 550°C was found to be 0.97 ± 0.13 J/m 2.

Determination of X-ray Elastic Constants in a Ti-14Al-21Nb Nb Alloy and a Ti-14Al-21Nb/SiC Metal Matrix Composite

1990 ◽  
Vol 34 ◽  
pp. 689-698 ◽  
Author(s):  
J. Jo ◽  
R. W. Hendricks ◽  
W. D. Brewer ◽  
Karen M. Brown
Keyword(s):  
Residual Stress ◽  
Plastic Deformation ◽  
Elastic Constant ◽  
Theoretical Calculation ◽  
Metal Matrix Composite ◽  
Elastic Constants ◽  
Metal Matrix ◽  
Intrinsic Value ◽  
X Ray

Residual stress values in a material are governed by the measurements of the atomic spacings in a specific crystallographic plane and the elastic constant for that plane. It has been reported that the value of the elastic constant depends on microstructure, preferred orientation, plastic deformation and morphology [1], Thus, the theoretical calculation of the elastic constant may deviate from the intrinsic value for a real alloy.

Quantitative Evaluation of the Interfacial Free Energies at A Solid-Liquid Lamellar Eutectic Interface

1981 ◽  
Vol 12 ◽  
Author(s):  
W. F. Kaukler ◽  
J. W. Rutter
Keyword(s):  
Free Energy ◽  
Solid Phase ◽  
Interfacial Free Energy ◽  
Eutectic System ◽  
Liquid Interfaces ◽  
Free Energies ◽  
Two Phases ◽  
Interfacial Free Energies ◽  
The Individual ◽  
Solid Liquid

The solid-liquid interfacial free energies of each of the individual phases comprising the eutectic system, Carbon Tetrabromide-Hexachloroethane, were measured as a function of composition using a “grain boundary groove” technique. Thermodynamic data were combined with groove shape measurements made from high resolution optical photomicrographs of the solid-liquid interfaces to give the interfacial free energy data. An interfacial free energy balance at the eutectic trijunction was performed to obtain all the forces acting on that point. The three interphase interfacial free energies at the eutectic trijunctions as well as a solid-solid phase boundary torque were evaluated.It was found that the solid-liquid interfacial free energies of the two phases of the eutectic could be evaluated from photomicrographs of growing or stationary eutectic interfaces. In addition, it was found that for a substantial range of freezing conditions the eutectic interface shape can be predicted from a knowledge of the interfacial free energies alone.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2019 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.51 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

scholarly journals Structure determination of an integral membrane protein at room temperature from crystalsin situ

2015 ◽  
Vol 71 (6) ◽  
pp. 1228-1237 ◽  
Author(s):  
Danny Axford ◽  
James Foadi ◽  
Nien-Jen Hu ◽  
Hassanul Ghani Choudhury ◽  
So Iwata ◽  
...  
Keyword(s):  
Membrane Protein ◽  
Structure Determination ◽  
Room Temperature ◽  
Protein Structures ◽  
Integral Membrane Protein ◽  
Data Sets ◽  
X Ray Diffraction ◽  
Haemophilus Influenza

The structure determination of an integral membrane protein using synchrotron X-ray diffraction data collected at room temperature directly in vapour-diffusion crystallization plates (in situ) is demonstrated. Exposing the crystalsin situeliminates manual sample handling and, since it is performed at room temperature, removes the complication of cryoprotection and potential structural anomalies induced by sample cryocooling. Essential to the method is the ability to limit radiation damage by recording a small amount of data per sample from many samples and subsequently assembling the resulting data sets using specialized software. The validity of this procedure is established by the structure determination ofHaemophilus influenzaTehA at 2.3 Å resolution. The method presented offers an effective protocol for the fast and efficient determination of membrane-protein structures at room temperature using third-generation synchrotron beamlines.

Photoemission Study of the Si, Ge Epitaxial Growth Process Using Surfactants

1992 ◽  
Vol 259 ◽  
Author(s):  
Xiaoyu Yang ◽  
Renyu Cao ◽  
Jeff Terry ◽  
Piero Pianetia
Keyword(s):  
Free Energy ◽  
Growth Process ◽  
Room Temperature ◽  
Energy Deposition ◽  
Low Energy ◽  
Heteroepitaxial Growth ◽  
Low Energy Electron Diffraction ◽  
Low Energy Electron ◽  
Photoemission Study

ABSTRACTHeteroepitaxial growth of Ge on Si(100) and Si on Ge(100) surfaces with Sb as a surfactant has been investigated by in situ high resolution photoemission and low energy electron diffraction (LEED). Our results show that an ordered monolayer of Sb atoms saturate the surface dangling bonds and consequently lower the surface free energy. Deposition of Ge or Si on the Sb/Si(100) or Sb/Ge(100) surfaces either at room temperature, followed by mild annealing or deposition at elevated temperature, result in an epitaxial layer of Ge or Si on the substrate, respectively. We provide clear experimental evidence that the deposited Ge or Si atoms changes position with the surface Sb atoms in this process. Ge or Si atoms occupy the epitaxial sites previously occupied by the Sb atoms. The Sb atoms in turn segregate to the surface and form a new ordered layer. The Bi-assisted growth process is also discussed.

Sign in / Sign up

Export Citation Format

Share Document