In situ TEM observations of room temperature dislocation climb at interfaces in nanolayered Al/Nb composites

2010 ◽  
Vol 63 (4) ◽  
pp. 363-366 ◽  
Author(s):  
Nan Li ◽  
J. Wang ◽  
J.Y. Huang ◽  
A. Misra ◽  
X. Zhang
Keyword(s):  
Room Temperature ◽  
Dislocation Climb ◽  
In Situ Tem

In-Situ Tem Investigation During Thermal Cycling of thin Copper Films

1996 ◽  
Vol 436 ◽  
Author(s):  
R.-M. Keller ◽  
W. Sigle ◽  
S. P. Baker ◽  
O. Kraft ◽  
E. Arzt
Keyword(s):  
Grain Growth ◽  
Room Temperature ◽  
Dislocation Motion ◽  
In Situ Tem ◽  
Copper Films ◽  
Stress Evolution ◽  
Cu Films ◽  
Transmission Electron ◽  
Insight Into

AbstractIn-situ transmission electron microscopy (TEM) was performed to study grain growth and dislocation motion during temperature cycles of Cu films with and without a cap layer. In addition, the substrate curvature method was employed to determine the corresponding stresstemperature curves from room temperature up to 600°C. The results of the in-situ TEM investigations provide insight into the microstructural evolution which occurs during the stress measurements. Grain growth occurred continuously throughout the first heating cycle in both cases. The evolution of dislocation structure observed in TEM supports an explanation of the stress evolution in both capped and uncapped films in terms of dislocation effects.

scholarly journals In Situ TEM Observations of Heavy Ion Damage in Gallium Arsenide

1988 ◽  
Vol 100 ◽  
Author(s):  
M. W. Bench ◽  
I. M. Robertson ◽  
M. A. Kirk
Keyword(s):  
Low Temperature ◽  
Room Temperature ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Heavy Ion ◽  
In Situ Tem ◽  
Accelerator Facility ◽  
Transmission Electron ◽  
Ion Accelerator

ABSTRACTTransmission electron microscopy experiments have been performed to investigate the lattice damage created by heavy-ion bombardments in GaAs. These experiments have been performed in situ by using the HVEN - Ion Accelerator Facility at Argonne National Laboratory. The ion bcorbardments (50 keV Ar+ and Kr+) and the microscopy have been carried out at temperatures rangrin from 30 to 300 K. Ion fluences ranged from 2 × 1011 to 5 × 1013 ions cm−2.Direct-inpact amorphization is observed to occur in both n-type and semi-insulating GaAs irradiated to low ion doses at 30 K and room temperature. The probability of forming a visible defect is higher for low temperature irradiations than for room temperature irradiations. The amorphous zones formed at low temperature are stable to temperatures above 250 K. Post implantation annealing is seen to occur at room temperature for all samples irradiated to low doses until eventually all visible damage disappears.

In situ TEM study of irradiation-induced transformation in TiNi shape memory alloys

2003 ◽  
Vol 792 ◽  
Author(s):  
X. T. Zu ◽  
F.R. Wan ◽  
S. Zhu ◽  
L. M. Wang
Keyword(s):  
Phase Transformation ◽  
Martensitic Transformation ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Electron Irradiation ◽  
Room Temperature ◽  
Critical Voltage ◽  
In Situ Tem ◽  
In Situ Observation

ABSTRACTTiNi shape memory alloy (SMA) has potential applications for nuclear reactors and its phase stability under irradiation is becoming an important topic. Some irradiation-induced diffusion-dependent phase transformations, such as amorphization, have been reported before. In the present work, the behavior of diffusion-independent phase transformation in TiNi SMA was studied by electron irradiation at room temperature. The effect of irradiation on the martensitic transformation of TiNi shape memory alloys was studied by Transmission Electron Microscopy (TEM) with in-situ observation and differential scanning calorimeter (DSC). The results of TEM and DSC measurements show that the microstructure of samples is R phase at room temperature. Electron irradiations were carried out using several different TEM with accelerating voltage of 200 kV, 300 kV, 400 kV and 1000 kV. Also the accelerating voltage in the same TEM was changed to investigate the critical voltage for the effect of irradiation on phase transformation. It was found that a phase transformation occurred under electron irradiation above 320 kV, but never appeared at 300 kV or lower accelerating voltage. Such phase transformation took place in a few seconds of irradiation and was independent of atom diffusion. The mechanism of Electron-irradiation-induced the martensitic transformation due to displacements of atoms from their lattice sites produced by the accelerated electrons.

scholarly journals In Situ Atomic-Scale Observation of Dislocation Climb and Grain Boundary Transformation in Nanostructured Metal

2021 ◽  
Author(s):  
Shufen Chu ◽  
Pan Liu ◽  
Yin Zhang ◽  
Xiaodong Wang ◽  
Shuangxi Song ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Grain Boundary ◽  
Room Temperature ◽  
Atomic Plane ◽  
Dislocation Core ◽  
Dislocation Climb ◽  
Atomic Scale ◽  
Atomic Column ◽  
Nanostructured Metal

Abstract We report atomic-scale observations of grain boundary (GB) dislocation climb in nanostructured Au during in situ straining at room temperature. Climb of a dislocation occurs by stress-induced reconstruction of two atomic columns at the edge of an extra half atomic plane in the dislocation core. Different from the conventional belief of dislocation climb by destruction or construction of a single atomic column at the dislocation core, the new atomic route is demonstrated to be energetically favorable by Monte Carlo simulations. Our in situ observations also reveal GB transformation through dislocation climb, which suggests a means of controlling microstructures and properties of nanostructured metals.

In-Situ Transmission Elecron Microscopy (TEM) Study of the Sintering of Sputtered Copper Nanoparticles on (001) Copper

1997 ◽  
Vol 3 (S2) ◽  
pp. 401-402
Author(s):  
M. Yeadon ◽  
J.C. Yang ◽  
R.S. Averback ◽  
J.W. Bullard ◽  
D.L. Olynick ◽  
...  
Keyword(s):  
Gas Phase ◽  
Copper Nanoparticles ◽  
Room Temperature ◽  
Copper Substrate ◽  
In Situ Tem ◽  
Single Particles ◽  
Fine Grain ◽  
Structural And Electrical Properties ◽  
Nanophase Materials

The large surface area: volume ratios and fine grain size of nanophase materials give rise to novel and exciting structural and electrical properties that are of considerable scientific and technological interest. Using copper as a model system we have investigated the sintering of sputtered copper nanoparticles (4-20nm diameter) with a copper substrate in a novel UHV in-situ TEM.The nanoparticles were generated in a UHV chamber built into the side of the column by sputtering in 1.5Torr Ar. They were transported into the microscope in the gas phase and deposited on an electron transparent (001) copper foil mounted on a heated support. A typical bright-field (BF) image of the sample immediately after deposition at room temperature is shown in Fig. 1. The particles have assumed a random orientation on the substrate and remain stable for many hours at room temperature. The presence of both single particles and agglomerates of particles is evident in this image and examples are labelled ‘P’ and ‘A’, respectively

Deformation-Induced Nanocrystallization in Al-Rich Metallic Glasses

2006 ◽  
Vol 114 ◽  
pp. 123-132 ◽  
Author(s):  
Nancy Boucharat ◽  
Rainer J. Hebert ◽  
Harald Rösner ◽  
Gerhard Wilde
Keyword(s):  
Metallic Glasses ◽  
Room Temperature ◽  
High Pressure Torsion ◽  
In Situ Tem ◽  
Number Density ◽  
High Number Density ◽  
Glass Forming ◽  
Processing Strategies ◽  
Improved Performance

Deformation-induced nanocrystallization has been investigated in a marginally Al88Y7Fe5 glass forming alloy. Conventional calorimetry and microstructural analyses of materials that have been subjected to high pressure torsion straining (HPT) at room temperature indicate the development of an extremely high number density of small Al nanocrystals. The nanocrystals appear to be distributed homogeneously throughout the sample without any evidence of strong coarsening. Moreover, the comparison between nanocrystallization caused by the application of either HPT, cold-rolling or in-situ TEM tensile straining yielded the identification of the probable mechanisms underlying the formation of nanocrystals. These results form the basis for the development of advanced processing strategies for producing new nanostructures with high nanocrystal number densities which allow increased stability and improved performance.

Amorphization of PLZT Material by 1.5 MeV Krypton Ion Irradiation with In Situ TEM Observation

1992 ◽  
Vol 268 ◽  
Author(s):  
L.M. Wang ◽  
A.Y. Wu ◽  
R.C. Ewing
Keyword(s):  
Single Crystals ◽  
Room Temperature ◽  
Ion Irradiation ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Irradiation Temperature ◽  
In Situ Tem

ABSTRACTPLZT 9/65/35 single crystals were irradiated with 1.5 MeV krypton ions at 25–450°C in the HVEM-Tandem Facility at Argonne National Laboratory. In-situ TEM was performed during irradiation in order to determine the critical amorphization dose. At room temperature, the material was completely amorphized after a dose of only 1.9×1014 ions/cm2, less than one fifth of the critical amorphization dose for silicon (1×1015 ions/cm2). The critical amorphization dose for the PLZT material increased with increasing irradiation temperature. At 450°C, amorphization was not observed after a dose of 1.1×10 15ions/cm2.

Formation of Hollow Zinc Oxide by Oxidation and Subsequent Thermal Treatment

2008 ◽  
Vol 135 ◽  
pp. 11-14 ◽  
Author(s):  
Jung Goo Lee ◽  
Ryusuke Nakamura ◽  
Daisuke Tokozakura ◽  
Hideo Nakajima ◽  
Hirotaro Mori ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Thermal Treatment ◽  
Oxide Layer ◽  
Room Temperature ◽  
Carbon Film ◽  
In Situ Tem ◽  
Zinc Vapor ◽  
Amorphous Carbon Film ◽  
Subsequent Thermal Treatment

The formation of hollow zinc oxide has been studied by oxidation and subsequent thermal treatment of nanometer-sized zinc particles using in-situ TEM. The zinc particles produced under UHV condition were exposed to air at room temperature for 0.6 ks, which resulted in the formation of oxide layer with thickness of 3 nm. Subsequent heating inside UHV chamber of TEM induced the evaporation of the inner zinc, which resulted in the formation of hollow zinc oxide. The produced hollow zinc oxide had the wurtzite structure. Based upon the vapor pressure of the inner zinc, it seems reasonable to consider that the internal zinc vapor leaks away through the interface between the oxide layer and the amorphous carbon film used as a supporting substrate.

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