Formation of Amorphous Graded Structure in Bi3Pb7 Intermetallic Compounds under Strong Gravitational Field

2009 ◽  
Vol 289-292 ◽  
pp. 357-360 ◽  
Author(s):  
Tsutomu Mashimo ◽  
Yusuke Iguchi ◽  
Rabaya Bagum ◽  
Tomokazu Sano ◽  
S. Takeda ◽  
...  
Keyword(s):  
Gravitational Field ◽  
Intermetallic Compound ◽  
Intermetallic Compounds ◽  
Amorphous Structure ◽  
Strong Gravitational Field ◽  
Graded Structure ◽  
Homogeneous Phase ◽  
Graded Structures ◽  
Gravity Direction

A visible four-layers structure with anomalous nano-sturucture was formed from a homogeneous -phase Bi3Pb7 intermetallic compound under a strong gravitational field (1.02x106 G, 130°C, 100 hours). In the 4th layer (lowest-gravity region), pure Bi particles precipitate. In the 2nd 3rd layers, composition graded structures, where Pb content increased along the gravity direction, were formed. It was found that the very broad XRD peak appeared in the 2nd layer, which indicated that an amorphous structure was contained.

Sedimentation of Impurity Atoms in InSb Semiconductor under a Strong Gravitational Field

2009 ◽  
Vol 289-292 ◽  
pp. 319-322 ◽  
Author(s):  
Yusuke Iguchi ◽  
Masao Ono ◽  
Satoru Okayasu ◽  
Tsutomu Mashimo
Keyword(s):  
Gravitational Field ◽  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
Atomic Scale ◽  
Semiconductor Materials ◽  
Strong Gravitational Field ◽  
Impurity Atoms ◽  
Graded Structure ◽  
Alloys And Compounds ◽  
Crystal Wafer

An atomic-scale graded structure has been formed by sedimentation of substitutional atoms under an ultra-strong gravitational field of 1 million G level in alloys and compounds. In this study, we investigate the sedimentation of impurity atoms in semiconductor materials under a strong gravitational field. High-temperature ultracentrifuge experiments (0.59×106 G, 400°C, 60 hours) have been performed on an InSb single crystal wafer which surface was coated with Ge by means of Physical Vapor Deposition (PVD). It was observed that the penetration depth of diffused Ge atoms under the gravitational field was several times larger than under terrestrial field at the same temperatures.

Application of Hrem in Studying Amorphisation of Intermetallic Compounds

1985 ◽  
Vol 62 ◽  
Author(s):  
D. E. Luzzi ◽  
H. Mori ◽  
H. Fujita ◽  
M. Meshii
Keyword(s):  
High Resolution ◽  
Intermetallic Compound ◽  
Intermetallic Compounds ◽  
Electron Irradiation ◽  
Driving Force ◽  
Amorphous Materials ◽  
Alloy System ◽  
Amorphous Structure ◽  
Ti Alloy ◽  
Special Significance

ABSTRACTElectron irradiation induces many intermetallic compounds to become amorphous. As this irradiation is capable of producing only isolatedpoint defects for each collision event, an understanding of this amorphisation proqess has a special significance with respect to the understanding of amorphous materials. This paper will report the results of HREM observations of an intermetallic compound in the Cu-Ti alloy system. High resolution micrographs will be presented to demonstrate that the energy associated with the irradiation induced chemical disordering is the major driving force in the amorphisation process. Also, the utility of the HREM in the study of amorphisation and the amorphous structure will be discussed.

Sedimentation of Substitutional Solute Atoms in Intermetallic Compound of Bi-Pb System under Ultra-Strong Gravitational Field

2005 ◽  
Vol 237-240 ◽  
pp. 1101-1106 ◽  
Author(s):  
Masao Ono ◽  
Xin Sheng Huang ◽  
Takahiro Kinoshita ◽  
Hideto Ueno ◽  
Toyotaka Osakabe ◽  
...  
Keyword(s):  
Gravitational Field ◽  
Intermetallic Compound ◽  
Time Duration ◽  
Experimental Conditions ◽  
Strong Gravitational Field ◽  
Weak Gravitational Field ◽  
Substitutional Solute ◽  
Starting State ◽  
Solute Atoms ◽  
Composition Changes

Ultra-strong gravitational field can induce sedimentation of even atoms in condensed matter. We had realized sedimentation of substitutional solute atoms in some miscible alloys. In this study, the ultra-centrifuge experiments were performed on an intermetallic compound of Bi-Pb system (Bi3Pb7) by changing time duration of experiment time (experimental conditions; maximum centrifugal force: 1.0x106g level, temperature: 130-150 °C, duration: 30-150h, state: solid). Composition changes were observed in the centrifuged samples. And, it was found that the Bi phase appeared from starting state of Bi3Pb7 around the weak gravitational field region of the sample. These results showed that sedimentation of substitutional solute atoms occurred, and induced the structure change in intermetallic compounds.

MD Simulation of Ionic Crystal under Strong Gravitational Field

2015 ◽  
Vol 363 ◽  
pp. 151-155
Author(s):  
Takahiro Kinoshita ◽  
Takashi Kawakami ◽  
Katsuyuki Kawamura ◽  
Tsutomo Mashimo
Keyword(s):  
Gravitational Field ◽  
Ionic Crystal ◽  
Md Simulation ◽  
Lattice Vibration ◽  
Md Simulations ◽  
Vibration Spectra ◽  
Strong Gravitational Field ◽  
Anisotropic Lattice ◽  
Simulation Results ◽  
Gravity Direction

Molecular dynamics (MD) simulations were performed to investigate unique crystalline states of typical ionic crystal at condition of a strong gravitational field (one million G). The simulation results showed that lattice vibration spectra of anion and cation along the gravity direction were different from the spectra along normal directions of the gravity. It is also shown that the shapes of spectra along the gravity are obviously different from the others along normal directions of the gravity. In addition, the peaks of spectra along the gravity were shifted. The simulation results showed that anisotropic lattice vibration spectra were induced by strong gravitational field, and it is insisted that the unique crystalline states and physical properties are induced by strong gravitational field.

Formation of atomic-scale graded structure in Se-Te semiconductor under strong gravitational field

2007 ◽  
Vol 101 (11) ◽  
pp. 113502 ◽  
Author(s):  
Xinsheng Huang ◽  
Masao Ono ◽  
Hideto Ueno ◽  
Yusuke Iguchi ◽  
Takeshi Tomita ◽  
...  
Keyword(s):  
Gravitational Field ◽  
Atomic Scale ◽  
Strong Gravitational Field ◽  
Graded Structure

scholarly journals Heat Treatment-Induced Microstructure and Property Evolution of Mg/Al Intermetallic Compound Coatings Prepared by Al Electrodeposition on Mg Alloy from Molten Salt Electrolytes

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1407
Author(s):  
Tianyu Yao ◽  
Kui Wang ◽  
Haiyan Yang ◽  
Haiyan Jiang ◽  
Jie Wei ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Intermetallic Compound ◽  
Intermetallic Compounds ◽  
Mg Alloy ◽  
X Ray Diffraction ◽  
Electron Backscattered Diffraction ◽  
Alloy Matrix ◽  
Comprehensive Properties ◽  
Compound Coatings ◽  
Compound Coating

A method of forming an Mg/Al intermetallic compound coating enriched with Mg17Al12 and Mg2Al3 was developed by heat treatment of electrodeposition Al coatings on Mg alloy at 350 °C. The composition of the Mg/Al intermetallic compounds could be tuned by changing the thickness of the Zn immersion layer. The morphology and composition of the Mg/Al intermetallic compound coatings were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and electron backscattered diffraction (EBSD). Nanomechanical properties were investigated via nano-hardness (nHV) and the elastic modulus (EIT), and the corrosion behavior was studied through hydrogen evolution and potentiodynamic (PD) polarization. The compact and uniform Al coating was electrodeposited on the Zn-immersed AZ91D substrate. After heat treatment, Mg2Al3 and Mg17Al12 phases formed, and as the thickness of the Zn layer increased from 0.2 to 1.8 μm, the ratio of Mg2Al3 and Mg17Al12 varied from 1:1 to 4:1. The nano-hardness increased to 2.4 ± 0.5 GPa and further improved to 3.5 ± 0.1 GPa. The Mg/Al intermetallic compound coating exhibited excellent corrosion resistance and had a prominent effect on the protection of the Mg alloy matrix. The control over the ratio of intermetallic compounds by varying the thickness of the Zn immersion layer can be an effective approach to achieve the optimal comprehensive performance. As the Zn immersion time was 4 min, the obtained intermetallic compounds had relatively excellent comprehensive properties.

Crystal-Grain Refinement of Materials under an Ultra-Strong Gravitational Field

2006 ◽  
pp. 639-642
Author(s):  
Y. Iguchi ◽  
H. Shibata ◽  
Y. Uchida ◽  
Xin Sheng Huang ◽  
Masao Ono ◽  
...  
Keyword(s):  
Gravitational Field ◽  
Grain Refinement ◽  
Strong Gravitational Field

scholarly journals Diffusion Barrier Performance of AlCrTaTiZr/AlCrTaTiZr-N High-Entropy Alloy Films for Cu/Si Connect System

Entropy ◽  
2020 ◽  
Vol 22 (2) ◽  
pp. 234
Author(s):  
Chunxia Jiang ◽  
Rongbin Li ◽  
Xin Wang ◽  
Hailong Shang ◽  
Yong Zhang ◽  
...  
Keyword(s):  
Intermetallic Compounds ◽  
Diffusion Barrier ◽  
Lattice Mismatch ◽  
Copper Film ◽  
Amorphous Structure ◽  
High Entropy Alloy ◽  
Alloy Films ◽  
High Entropy ◽  
Atom Diffusion ◽  
Barrier Performance

In this study, high-entropy alloy films, namely, AlCrTaTiZr/AlCrTaTiZr-N, were deposited on the n-type (100) silicon substrate. Then, a copper film was deposited on the high-entropy alloy films. The diffusion barrier performance of AlCrTaTiZr/AlCrTaTiZr-N for Cu/Si connect system was investigated after thermal annealing for an hour at 600 °C, 700 °C, 800 °C, and 900 °C. There were no Cu-Si intermetallic compounds generated in the Cu/AlCrTaTiZr/AlCrTaTiZr-N/Si film stacks after annealing even at 900 °C through transmission electron microscopy (TEM) and atomic probe tomography (APT) analysis. The results indicated that AlCrTaTiZr/AlCrTaTiZr-N alloy films can prevent copper diffusion at 900 °C. The reason was investigated in this work. The amorphous structure of the AlCrTaTiZr layer has lower driving force to form intermetallic compounds; the lattice mismatch between the AlCrTaTiZr and AlCrTaTiZ-rN layers increased the diffusion distance of the Cu atoms and the difficulty of the Cu atom diffusion to the Si substrate.

CRYSTALLINE STRUCTURE AND PHYSICAL PROPERTIES OF UCo2Al3

2004 ◽  
Vol 18 (30) ◽  
pp. 3905-3914
Author(s):  
E. VERDÍN ◽  
R. ESCUDERO
Keyword(s):  
Intermetallic Compound ◽  
Physical Properties ◽  
Single Crystal ◽  
Intermetallic Compounds ◽  
Heavy Fermion ◽  
Ferromagnetic Transition ◽  
Crystallographic Characteristics ◽  
Heavy Fermion Behavior ◽  
Small Single Crystal ◽  
Weak Ferromagnetic

Some intermetallic compounds which contain uranium or cerium present heavy fermion characteristics. Take, for example, in the UM 2 Al 3 ( M = Pd , Ni ) family, superconductivity and magnetism coexist and present heavy fermion behavior. This work presents the crystallographic characteristics and physical properties of a new compound of this family; the intermetallic compound UCo 2 Al 3. Our initial crystallographic studies performed in a small single crystal show that the structure is hexagonal and similar to the UNi 2 Al 3 and UPd 2 Al 3 parent compounds. The space group is P6/mmm with a=5.125 Å and c=4.167 Å crystalline parameters. Measurements of resistivity and magnetization performed on the single crystal reveal that the compound is not superconducting when measured at about 1.8 K. The compound is highly anisotropic and features related to Kondo-like behavior are observed. A weak ferromagnetic transition is observed at a temperature of about 20 K.

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