scholarly journals Interpreting Experimental Results from Shock Impacts on Single Crystal PETN in the Context of Continuum Models

2019 ◽  
Vol 45 (2) ◽  
pp. 284-294
Author(s):  
Darby J. Luscher ◽  
Marc J. Cawkwell ◽  
Kyle J. Ramos ◽  
Richard L. Sandberg ◽  
Cynthia A. Bolme
Keyword(s):  
Single Crystal ◽  
Experimental Results ◽  
Continuum Models ◽  
Shock Impacts

scholarly journals Simulation of the External Pressure Influence on the Micro-Structural Evolution of a Single Crystal Ni-Based Superalloy

2011 ◽  
Vol 278 ◽  
pp. 247-252
Author(s):  
Inmaculada Lopez-Galilea ◽  
Stephan Huth ◽  
Suzana Gomes Fries ◽  
Ingo Steinbach ◽  
Werner Theisen
Keyword(s):  
Single Crystal ◽  
Microstructural Evolution ◽  
Phase Field ◽  
Structural Evolution ◽  
Field Method ◽  
External Pressure ◽  
Experimental Results ◽  
Alloying Elements ◽  
Phase Field Method

The phase field method has been applied to simulate the microstructural evolution of a commercial single crystal Ni-based superalloy during both, HIP and annealing treatments. The effects of applying high isostatic pressure on the microstructural evolution, which mainly retards the diffusion of the alloying elements causing the loss of the orientational coherency between the phases is demonstrated by the simulation and experimental results

Synthesis, Structure and Magnetism of ErCoIn5

2004 ◽  
Vol 848 ◽  
Author(s):  
Evan Lyle Thomas ◽  
Erin E. Erickson ◽  
Monica Moldovan ◽  
David P. Young ◽  
Julia Y. Chan
Keyword(s):  
Magnetic Properties ◽  
Electrical Resistivity ◽  
Magnetic Susceptibility ◽  
Single Crystal ◽  
Experimental Results ◽  
Flux Growth ◽  
X Ray Diffraction ◽  
Metallic Behavior ◽  
X Ray ◽  
Growth Method

AbstractA new member of the LnMIn5 family, ErCoIn5, has been synthesized by a flux-growth method. The structure of ErCoIn5 was determined by single crystal X-ray diffraction. It crystallizes in the tetragonal space group P4/mmm, Z = 1, with lattice parameters a = 4.5400(4) and c = 7.3970(7) Å, and V = 152.46(2) Å3. Electrical resistivity data show metallic behavior. Magnetic susceptibility measurements show this compound to be antiferromagnetic with TN = 5.1 K. We compare these experimental results with those of LaCoIn5 in an effort to better understand the effect of the structural trends observed on the transport and magnetic properties.

CHANNELING ENERGY LOSS IN SILICON BY USING NUMERICAL AND EXPERIMENTAL METHODS

2011 ◽  
Vol 25 (28) ◽  
pp. 2171-2181 ◽  
Author(s):  
OMAR EL BOUNAGUI ◽  
HASSANE ERRAMLI
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Energy Loss ◽  
Single Crystal ◽  
Experimental Methods ◽  
Silicon Single Crystal ◽  
Experimental Results ◽  
Monte Carlo Simulation Program ◽  
Shed Light ◽  
Good Agreement

A Monte Carlo simulation program was developed to calculate the variations of the channeled to random electronic stopping powers of He + in an energy 4 MeV in silicon single crystal along the major 〈100〉, 〈110〉 and 〈111〉 axes. This paper discusses both simulation and experimental results that shed light on the contribution of these factors. Results obtained by our simulation are in good agreement with the experimental results.

In Situ Etching Rate Measurement of Si with XeF2

1986 ◽  
Vol 68 ◽  
Author(s):  
K. R. Padmanabhan ◽  
S. Bhowmick ◽  
R. Shaver ◽  
Zhang Zu Hua ◽  
J. C. Buchholz
Keyword(s):  
Single Crystal ◽  
Etching Rate ◽  
Experimental Results ◽  
Rate Measurement ◽  
Random Orientation ◽  
Appreciable Difference ◽  
Induced Decomposition ◽  
Ion Backscattering

AbstractIon backscattering and channeling techniques have been employed to measure the etching rate of amorphous and single crystal Si by XeF2 under similar conditions.Both (100) Si on sapphire and (111) Si on spinel showed higher etching rates compared to amorphous Si.However, measurements of the etching rate using a Si cell aligned to the axis and along the planes under similar conditions did not show appreciable difference in the etching rate compared to the etching rate with random orientation of the cell.Presence of the analyzing 4He+ beam during etching enhances the etching rate to twice the value when compared to post etching analysis with the same beam.The enhancement of the etching rate due to ion induced decomposition of XeF2 have been considered in the explanation of the experimental results.

Directional Solidification Behavior of CMSX-6 Superalloy

2014 ◽  
Vol 788 ◽  
pp. 554-559
Author(s):  
Shuai Zheng ◽  
Yu Liang Jia ◽  
Jiao Tang
Keyword(s):  
Single Crystal ◽  
Directional Solidification ◽  
Thermal Gradient ◽  
First Generation ◽  
Primary Dendrite ◽  
Solidification Rate ◽  
Experimental Results ◽  
Single Crystal Superalloy ◽  
Solidification Behavior ◽  
Rate Range

The directional solidification behavior of a first generation single crystal superalloy CMSX-6 was investigated. The solidification rate range in 25μm/s to 100μm/s and a thermal gradient G of 30K/cm were used for the present study. The experimental results show that the primary dendrite arm space (PDAS) decreased from (432±8) μm to (369±4) μm as the solidification rate increased, and the sizes of the eutectic pools also decreased as the solidification rate increased. And the volume fractions of eutectic γ/γ' were about 7% to 9% with different solidification rate. The γ/γ'- eutectic was comprised with coarse γ' phase and fine γ/γ' network. The morphology of the γ/γ’ eutectic supported the possibility that the solidification of γ/γ’ eutectic initiates with the formation of fine γ/γ’.

Microscopy and microindentation mechanics of single crystal Fe−3 wt. % Si: Part II. TEM of the indentation plastic zone

1993 ◽  
Vol 8 (6) ◽  
pp. 1300-1310 ◽  
Author(s):  
W. Zielinski ◽  
H. Huang ◽  
W.W. Gerberich
Keyword(s):  
Plastic Strain ◽  
Plastic Zone ◽  
Single Crystal ◽  
Strain Gradient ◽  
Continuum Models ◽  
Large Loop ◽  
Direct Observations ◽  
Small Loop ◽  
Secondary Reactions ◽  
Plastic Strain Gradient

Direct observations of dislocation arrangements about a range of microindentations into the [100] face of an Fe−3 wt. % Si single crystal have been accomplished. Dislocations of both large loop character initiated from the indenter and small loop character initiated as secondary reactions are found. Analysis of these allows the various contributions to the plastic strain gradient around the indentation to be assessed, with the experimental observations being reasonably consistent with continuum models.

Nitrogen Nuclear Quadrupole Interactions in RDX, β-HMX and Cocaine Systems

1997 ◽  
Vol 52 (3) ◽  
pp. 241-248
Author(s):  
Ranjit Pati ◽  
T. P. Das ◽  
N. Sahoo ◽  
S.N. Ray
Keyword(s):  
Single Crystal ◽  
Quantitative Agreement ◽  
Experimental Results ◽  
Coupling Constants ◽  
Hartree Fock ◽  
Quadrupole Interactions ◽  
Nuclear Quadrupole Interactions ◽  
Electron Distributions ◽  
Nuclear Quadrupole ◽  
Theory And Experiment

AbstractUsing the Hartree-Fock-Roothaan procedure, the nuclear quadrupole interactions (NQI) of the 14N (I = 1) nucleus in the energetically important molecules RDX, β-HMX and the physiologically important molecule Cocaine, are studied. The coupling constants (e2 q Q) and asymmetry parameters (η) for the three ring nitrogens in RDX are found to be -5.671, -5.808 and -5.838 MHz and 0.542, 0.556 and 0.562, respectively, in good quantitative agreement with the experimental results of 5.735, 5.799 and 5.604 MHz for the magnitudes of e2qQ and 0.6215, 0.6146 and 0.6024 for η obtained in the single crystal. For β-HMX, where two sets of e2 q Q and η are expected from symmetry considerations, our calculated values are -5.936 and -6.069 MHz for e2 q Q and 0.432 and 0.490 for η , compared to experimentally measured magnitudes of 5.791 and 6.025 MHz and η-values of 0.4977 and 0.5180, respectively, obtained in the single crystal. For Cocaine free base which contains only one 14N nucleus, our calculated values of e2 qQ and η are -5.038 MHz and 0.067, in very good agreement with the experimental results of 5.0229 MHz for the magnitude of e2 q Q and 0.0395 for η. Possible reasons for the small remaining differences between theory and experiment in e2 q Q and η for all three systems and the significant differences in trends over the three nitrogens in RDX between theory and experiment are discussed. Also, the calculated quadrupole interaction parameters for the 14N nuclei in the NO2 groups outside the ring for both RDX and β-HMX are presented with the hope that they will be measured in the future to provide a more complete understanding of the electron distributions in these systems.

Optimization of Ta Content of a Third Generation Ni3Al Base Single Crystal Superalloy

2015 ◽  
Vol 816 ◽  
pp. 304-309
Author(s):  
Song Ming Han ◽  
Wei Li ◽  
Yue Ma ◽  
Xin Bao Zhao ◽  
Shu Suo Li ◽  
...  
Keyword(s):  
Single Crystal ◽  
Thermodynamic Calculation ◽  
Volume Fraction ◽  
Primary Dendrite ◽  
Solution Treatment ◽  
Experimental Results ◽  
Single Crystal Superalloy ◽  
Third Generation ◽  
Primary Dendrite Arm Spacing ◽  
Calculation Results

In order to optimize the Ta content of a newly developed 3rd generation Ni3Al-based single crystal superalloy, a series of alloys with the varying of Ta content of 3.0, 4.2, 4.5, 6.0wt. % were prepared. The experimental results showed that with the addition of Ta, the size and volume fraction of bulky γ' phase significantly increased while the primary dendrite arm spacing decreased. Meanwhile, the difficulty of solution treatment significantly increased with increasing Ta content. And the thermodynamic calculation results showed that the volume fractions of γ' phase in this series of alloys were significantly higher than those of typical Ni based single crystal superalloys, indicating that the 3rd generation Ni3Al based single crystal superalloys can serve in the temperature of 1150oC to 1200oC.

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