The stresses in a face-centered cubic single crystal under uniaxial tension

AbstractThe compression of argon is measured between 10 K and 296 K up to 20 GPa and and up to 114 GPa at 296 K in diamond anvil cells. Three samples conditioning are used: (1) single crystal sample directly compressed between the anvils, (2) powder sample directly compressed between the anvils, (3) single crystal sample compressed in a pressure medium. A partial transformation of the face-centered cubic (fcc) phase to a hexagonal close-packed (hcp) structure is observed above 4.2–13 GPa. Hcp phase forms through stacking faults in fcc-Ar and its amount depends on pressurizing conditions and starting fcc-Ar microstructure. The quasi-hydrostatic equation of state of the fcc phase is well described by a quasi-harmonic Mie–Grüneisen–Debye formalism, with the following 0 K parameters for Rydberg-Vinet equation: $$V_0$$ V 0 = 38.0 Å$$^3$$ 3 /at, $$K_0$$ K 0 = 2.65 GPa, $$K'_0$$ K 0 ′ = 7.423. Under the current experimental conditions, non-hydrostaticity affects measured P–V points mostly at moderate pressure ($$\le$$ ≤ 20 GPa).

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A Study on the Uniaxial Tension of FCC Metals at Nano Level Using MD

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.32.255 ◽

2008 ◽

Vol 32 ◽

pp. 255-258

Author(s):

Bohayra Mortazavi ◽

Akbar Afaghi Khatibi

Keyword(s):

Molecular Dynamics ◽

Uniaxial Tension ◽

Md Simulations ◽

Dynamics Simulation ◽

Face Centered Cubic ◽

Engineering Strain ◽

Fcc Metals ◽

Engineering Stress ◽

Nano Science ◽

Face Centered

Molecular Dynamics (MD) are now having orthodox means for simulation of matter in nano-scale. It can be regarded as an accurate alternative for experimental work in nano-science. In this paper, Molecular Dynamics simulation of uniaxial tension of some face centered cubic (FCC) metals (namely Au, Ag, Cu and Ni) at nano-level have been carried out. Sutton-Chen potential functions and velocity Verlet formulation of Noise-Hoover dynamic as well as periodic boundary conditions were applied. MD simulations at different loading rates and temperatures were conducted, and it was concluded that by increasing the temperature, maximum engineering stress decreases while engineering strain at failure is increasing. On the other hand, by increasing the loading rate both maximum engineering stress and strain at failure are increasing.

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The strain hardening of micro-sized face-centered-cubic single crystal metals: A crystal plasticity study

AIP Advances ◽

10.1063/1.5051361 ◽

2018 ◽

Vol 8 (12) ◽

pp. 125208 ◽

Cited By ~ 1

Author(s):

Huili Guo ◽

Chenlin Li ◽

Xu Zhang ◽

Fulin Shang

Keyword(s):

Single Crystal ◽

Strain Hardening ◽

Crystal Plasticity ◽

Face Centered Cubic ◽

Face Centered

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Magnetic and magneto‐optic properties of thick face‐centered‐cubic Co single‐crystal films

Applied Physics Letters ◽

10.1063/1.111946 ◽

1994 ◽

Vol 64 (20) ◽

pp. 2736-2738 ◽

Cited By ~ 55

Author(s):

T. Suzuki ◽

D. Weller ◽

C.‐A. Chang ◽

R. Savoy ◽

T. Huang ◽

...

Keyword(s):

Single Crystal ◽

Face Centered Cubic ◽

Single Crystal Films ◽

Crystal Films ◽

Face Centered ◽

Magneto Optic

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Formation of Face Centered Cubic Titanium Thin Films on MgO(111) Single Crystal Substrate

Materials Science Forum ◽

10.4028/www.scientific.net/msf.913.264 ◽

2018 ◽

Vol 913 ◽

pp. 264-269

Author(s):

Lei Li ◽

Yan Liu ◽

Xiao Nan Mao ◽

Vincent Ji

Keyword(s):

Single Crystal ◽

Single Crystal Substrate ◽

Temperature Phase ◽

Face Centered Cubic ◽

Hexagonal Close Packed ◽

Crystal Substrate ◽

Cubic Structure ◽

Hcp Structure ◽

Face Centered ◽

Ti Films

High strength, low density, and excellent corrosion resistance are the main properties that make titanium attractive for a variety of applications. The phase structures and phase transitions of titanium, which are of tremendous scientific and technological interest, have attracted a great deal of attention for many years. In addition to hexagonal close packed α-Ti, high temperature phase β-Ti with body-centered cubic structure and ω-Ti with the hexagonal structure of high-pressure phase, the face-centered cubic structure, which is not in the P-T diagram of titanium, is observed in ultrathin films. In the present paper, the Ti films prepared by magnetron sputtering on MgO(111) single crystal substrate were investigated by means of X-Ray Diffraction (XRD) and High-Resolution Transmission Electron Microscope (HRTEM). The results showed that the Ti films grow epitaxial with a face centered cubic (fcc) structure even the thickness is up to about 50nm. With the thickness increases, the Ti films transformed to hexagonal close packed (hcp) structure and showed an epitaxial growth along (002)hcp-Ti direction. The results show that the onset thickness of fcc-hcp structure transformation is 50-100nm. The temperature and power of sputter affect the formation of fcc-Ti.

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Optical properties and carrier dynamics of ensembles of InP nanowires grown on non-single-crystal platforms

MRS Proceedings ◽

10.1557/proc-1178-aa01-04 ◽

2009 ◽

Vol 1178 ◽

Author(s):

Takehiro Onishi ◽

Andrew J. Lohn ◽

Nobuhiko P. Kobayashi

Keyword(s):

Optical Properties ◽

Single Crystal ◽

Quartz Substrate ◽

Chemical Vapor ◽

Blue Shift ◽

Growth Direction ◽

Longitudinal Optical ◽

Face Centered Cubic ◽

Single Crystal Surfaces ◽

Face Centered

AbstractOptically active InP nanowires were grown on a quartz substrate covered with a layer (100 nm) of hydrogenated amorphous silicon (a-Si:H) by metalorganic chemical vapor deposition (MOCVD), demonstrating that single-crystal semiconductor nanowires can be formed on non-single-crystal surfaces. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, cathodoluminescence (CL), and photoluminescence (PL) were used to characterize the structural and optical properties of the nanowires. The nanowires on a-Si:H grew in random directions with high density. The XRD suggests that nanowires having either hexagonal-close-packed or face-centered cubic lattices co-exist. The Raman spectrum shows peaks associated with transverse optical (TO) and longitudinal optical (LO) branches of InP. The CL intensity does not vary signi?cantly along the growth direction and appears to be originated from the entire structure of the nanowire when probed at various positions. The CL data suggests that recombination is slow enough to allow the carriers to diffuse the complete length of the nanowires (˜2 m in length) before recombining. The PL spectrum suggested the nanowire had a part that contributes to the observed blue shift while the other part had nearly bulk feature in their structure.

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Indentation size effects in face centered cubic single crystal thin films

Materials Science and Engineering A ◽

10.1016/j.msea.2005.05.075 ◽

2005 ◽

Vol 404 (1-2) ◽

pp. 281-290 ◽

Cited By ~ 31

Author(s):

Zong Zong ◽

Wole Soboyejo

Keyword(s):

Thin Films ◽

Single Crystal ◽

Size Effects ◽

Face Centered Cubic ◽

Indentation Size ◽

Face Centered

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In Situ HREM Observation of Phase Transformation Process in FePt and FePtCu Nanoparticles

MRS Proceedings ◽

10.1557/proc-0907-mm05-04 ◽

2005 ◽

Vol 907 ◽

Author(s):

Masatoshi Nakanishi ◽

Gen-ichi Furusawa ◽

Kokichi Waki ◽

Yasushi Hattori ◽

Takeo Kamino ◽

...

Keyword(s):

Phase Transformation ◽

Single Crystal ◽

Particle Formation ◽

Cubic Phase ◽

Fept Nanoparticles ◽

Crystal Formation ◽

Face Centered Cubic ◽

Shaped Particle ◽

Face Centered

AbstractThe processes of phase transformation in individual nanoparticles of FePt and FePtCu synthesized by the reverse micelle method, which are chemically homogeneous and monodisperse, have been investigated by an in-situ HREM observation in a FE-TEM. Polycrystalline FePt particles, initially of chemically disordered face-centered cubic phase (A1) were reconstructed into A1 single crystals between 25 °C and 650 °C, followed by phase transformation from A1 to chemically ordered face-centered tetragonal phase (L10) which began between 650 °C and 680 °C. The coalescence began concurrently with phase transformation, i. e., between 650 °C and 680 °C. They turned to be a round-shaped L10 particle between 680 °C and 720 °C. The single crystal formation, the phase transformation from A1 to L10, the coalescence and the round-shaped particle formation were also observed in the FePtCu nanoparticles. The temperatures of single crystal formation, phase transformation (and coalescence) and round-shaped particle formation of the FePtCu nanoparticles were between 25 °C and 500 °C, between 550 °C and 600 °C and between 600 °C and 650 °C, respectively. These temperatures were substantially lower than those for the FePt nanoparticles.

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