Studies of Extended Dislocation Configurations in HCP Silver-Tin Alloys

1968 ◽  
Vol 26 ◽  
pp. 268-269
Author(s):  
A. W. Ruff ◽  
L. K. Ives
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
Tin Alloys ◽  
Thin Foils ◽  
Transmission Electron ◽  
Hcp Structure ◽  
Means Of Transmission ◽  
Extended Dislocation

Recently we have reported the stacking fault energy in a series of hcp silver-tin alloys as a function of composition. The stacking fault energy was found to increase linearly with composition from 5.5 erg/cm2 for an 11.9 at.% tin alloy to 18.9 erg/cm2 for a 17.2 at.% tin alloy. Measurements were made on extended dislocation nodes and double-ribbons observed in thin foils by means of transmission electron microscopy. During the course of this investigation a number of dislocation configurations were observed as the result of interactions between extended dislocations lying on adjacent basal planes. Many of these configurations were identical to those which have been extensively studied by Delavignette and Amelinckx in hexagonal graphite. The same basal plane faulting pattern is found there as in the hcp structure. We have observed other configurations in these alloys that could be associated with cross-slip of basal dislocations or with their interactions with non-basal dislocations. It is the purpose of this paper to discuss faulting in the hcp structure and to describe several of the dislocation configurations observed in these silver-tin alloys.

THE STACKING-FAULT ENERGY IN α-SILVER – TIN ALLOYS

1967 ◽  
Vol 45 (2) ◽  
pp. 787-795 ◽  
Author(s):  
A. W. Ruff Jr. ◽  
L. K. Ives
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
Pure Silver ◽  
Tin Alloys ◽  
Transmission Electron ◽  
Direct Measurements ◽  
Extended Dislocation

Direct measurements by transmission electron microscopy on extended dislocation nodes in alloys of tin in silver have led to values for the intrinsic stacking-fault energy. The values decreased smoothly from 23 erg/cm2 for pure silver to 4.2 erg/cm2 for 7.8 at.% tin. The results are compared with previous determinations in other silver-base alloys.

Dislocations and stacking faults in stainless steel

1957 ◽  
Vol 240 (1223) ◽  
pp. 524-538 ◽  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Stainless Steel ◽  
Grain Boundaries ◽  
Stacking Faults ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
Thin Sections ◽  
Partial Dislocations ◽  
Transmission Electron

Further experiments by transmission electron microscopy on thin sections of stainless steel deformed by small amounts have enabled extended dislocations to be observed directly. The arrangement and motion of whole and partial dislocations have been followed in detail. Many of the dislocations are found to have piled up against grain boundaries. Other observations include the formation of wide stacking faults, the interaction of dislocations with twin boundaries, and the formation of dislocations at thin edges of the foils. An estimate is made of the stacking-fault energy from a consideration of the stresses present, and the properties of the dislocations are found to be in agreement with those expected from a metal of low stacking-fault energy.

DISLOCATION DISSOCIATION IN HIGH Tc BiSrCaCuO

1989 ◽  
Vol 03 (17) ◽  
pp. 1359-1362 ◽  
Author(s):  
FANG LIU ◽  
HUI GU ◽  
TIAN XIAO LIN ◽  
JIN LONG ZHANG ◽  
GUANG CHENG XIONG ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Basal Plane ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
High Tc ◽  
Type Formula ◽  
Transmission Electron ◽  
Dislocation Dissociation

Transmission electron microscopy (TEM) shows that the dislocation on basal plane (001) of high T c BiSrCaCuO can dissociate into 2 partials of the type [Formula: see text]. The related stacking fault energy is estimated of the order about µb/365 similar to that observed in Cu and implication of this finding has been discussed.

Tem Structural Studies on Zn+ Implanted and As+ /Zn+ Dually Implanted GaAs

1985 ◽  
Vol 45 ◽  
Author(s):  
E. Morita ◽  
J. Kasahara ◽  
M. Arai ◽  
S. Kawado
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Stacking Fault ◽  
Structural Studies ◽  
The Core ◽  
Partial Dislocations ◽  
Transmission Electron ◽  
Stacking Fault Tetrahedra ◽  
Means Of Transmission

ABSTRACTMicrodefects in Cr-doped SI LEC (001) GaAs wafers which were implanted with Zn+ or As /Zn and capless-annealed in an As ambient have been studied by means of transmission electron microscopy. Most of the microdefects in Zn +- implanted GaAs specimens were identified as precipitates and stacking fault tetrahedra (SFTs). Every SFT was accompanied by a precipitate at the apex. Most of the precipitates were distributed from Rp to Rp + 2∆Rp. Two types (α and β) of SFTs were differentiated by the arrangement of atoms in the core of the stair-rod partial dislocations bounding the periphery of the SFTs in a polar Frystal. β-SFTs were, however, predominantly formed in Zn+ implanted GaAs specimens. Dual implantation of As+ and Zn+ suppressed the formation of SFTs, but not that of precipitates. The formation of SFTs was found to be influenced by the deviation in stoichiometry.

Phenomena Associated with Oxygen in Titanium

1967 ◽  
Vol 25 ◽  
pp. 310-311
Author(s):  
E. U. Lee ◽  
P. A. Garner ◽  
J. S. Owens
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Microscope ◽  
Microstructural Changes ◽  
Electrolytic Polishing ◽  
Interstitial Impurities ◽  
Thin Foils ◽  
Transmission Electron ◽  
Iodide Titanium ◽  
Alpha Titanium

Evidence for ordering (1-6) of interstitial impurities (O and C) has been obtained in b.c.c. metals, such as niobium and tantalum. In this paper we report the atomic and microstructural changes in an oxygenated c.p.h. metal (alpha titanium) as observed by transmission electron microscopy and diffraction.Oxygen was introduced into zone-refined iodide titanium sheets of 0.005 in. thickness in an atmosphere of oxygen and argon at 650°C, homogenized at 800°C and furnace-cooled in argon. Subsequently, thin foils were prepared by electrolytic polishing and examined in a JEM-7 electron microscope, operated at 100 KV.

Simulation of three Dimensional Defect Images in Transmission Electron Microscopy

1976 ◽  
Vol 34 ◽  
pp. 470-471
Author(s):  
W. D. Cooper ◽  
C. S. Hartley ◽  
J. J. Hren
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Three Dimensional ◽  
Crystalline Lattice ◽  
Continuum Models ◽  
Thin Foils ◽  
Transmission Electron ◽  
Microscope Images ◽  
General Computer Program ◽  
General Computer

Interpretation of electron microscope images of crystalline lattice defects can be greatly aided by computer simulation of theoretical contrast from continuum models of such defects in thin foils. Several computer programs exist at the present time, but none are sufficiently general to permit their use as an aid in the identification of the range of defect types encountered in electron microscopy. This paper presents progress in the development of a more general computer program for this purpose which eliminates a number of restrictions contained in other programs. In particular, the program permits a variety of foil geometries and defect types to be simulated.The conventional approximation of non-interacting columns is employed for evaluation of the two-beam dynamical scattering equations by a piecewise solution of the Howie-Whelan equations.

scholarly journals Electron Microscopy Investigation of Magnetization Process in Thin Foils and Nanostructures

2007 ◽  
Vol 1026 ◽  
Author(s):  
Pascale Bayle-Guillemaud ◽  
Aurelien Masseboeuf ◽  
Fabien Cheynis ◽  
Jean-Christophe Toussaint ◽  
Olivier Fruchart ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Magnetic Anisotropy ◽  
Magnetic Induction ◽  
Perpendicular Magnetic Anisotropy ◽  
In Situ Observation ◽  
Magnetic Imaging ◽  
Thin Foils ◽  
Transmission Electron

AbstractThis paper presents investigations of magnetization configuration evolution during in-situ magnetic processes in materials exhibiting planar and perpendicular magnetic anisotropy. Transmission electron microscopy has been used to perform magnetic imaging. Fresnel contrasts in Lorentz Transmission Electron Microscopy (LTEM) and phase retrieval methods such as Transport of Intensity Equation (TIE) solving or electron holography have been implemented. These techniques are sensitive to magnetic induction perpendicular to the electron beam and can give access to a spatially resolved (resolution better than 10 nm) mapping of magnetic induction distribution and could be extended to dynamical studies during in-situ observation. Thin foils of FePd alloys with a strong perpendicular magnetic anisotropy (PMA) and self-assembled Fe dots are presented. Both are studied during magnetization processes exhibiting the capacities of in-situ magnetic imaging in a TEM.

Structural Properties of Amorphous Silicon Produced by Electron Irradiation

1999 ◽  
Vol 557 ◽  
Author(s):  
J. Yamasaki ◽  
S. Takeda
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Distribution Function ◽  
Structural Properties ◽  
Electron Irradiation ◽  
Low Temperatures ◽  
Crystalline Silicon ◽  
Transmission Electron ◽  
Amorphous Si ◽  
Means Of Transmission

AbstractThe structural properties of the amorphous Si (a-Si), which was created from crystalline silicon by 2 MeV electron irradiation at low temperatures about 25 K, are examined in detail by means of transmission electron microscopy and transmission electron diffraction. The peak positions in the radial distribution function (RDF) of the a-Si correspond well to those of a-Si fabricated by other techniques. The electron-irradiation-induced a-Si returns to crystalline Si after annealing at 550°C.

Nano-Thermometry: Transmission Electron Microscopy of Femtosecond Laser Irradiated Co/Si Multilayer Thin Foils

2005 ◽  
Vol 899 ◽  
Author(s):  
Yoosuf Picard ◽  
Steven M. Yalisove
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Amorphous Silicon ◽  
Heat Dissipation ◽  
Crystalline Silicon ◽  
Pulse Length ◽  
Multilayer Systems ◽  
Hole Edge ◽  
Thin Foils ◽  
Transmission Electron

AbstractPre-thinned foils composed of amorphous silicon and polycrystalline cobalt were irradiated using femtosecond pulse-length lasers at fluences sufficient for ablation (material removal). The resultant ablated hole and surrounding vicinity was studied using transmission electron microscopy to determine modifications to the structure. Evidence of cobalt silicide formation was observed within a 3 micron radius of the laser hole edge by use of selected area electron diffraction (SAED). In addition, elongated grains of crystalline silicon was observed within 500 nm of the laser hole edge, indicating melting of the amorphous silicon and heat dissipation slow enough to allow recyrstallization. This initial work demonstrates the use of pre-designed nanostructured multilayer systems as a method for nanoscale profiling of heat dissipation following pulsed laser irradiation.

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