In-situ TEM studies of ion-irradiation induced bubble development and mechanical deformation in model nuclear materials

ABSTRACTThe MIAMI* facility at the University of Huddersfield is one of a number of facilities worldwide that permit the ion irradiation of thin foils in-situ in a transmission electron microscope. MIAMI has been developed with a particular focus on enabling the in-situ implantation of helium and hydrogen into thin electron transparent foils, necessitating ion energies in the range 1 – 10 keV. In addition, however, ions of a variety of species can be provided at energies of up to 100 keV (for singly charged ions), enabling studies to focus on the build up of radiation damage in the absence or presence of implanted gas.This paper reports on a number of ongoing studies being carried out at MIAMI, and also at JANNuS (Orsay, France) and the IVEM / Ion Accelerator Facility (Argonne National Lab, US). This includes recent work on He bubbles in SiC and Cu; the former work concerned with modification to bubble populations by ion and electron beams and the latter project concerned with the formation of bubble super-lattices in metals.A study is also presented consisting of experiments aimed at shedding light on the origins of the dimensional changes known to occur in nuclear graphite under irradiation with either neutrons or ions. Single crystal graphite foils have been irradiated with 60 keV Xe ions in order to create a non-uniform damage profile throughout the foil thickness. This gives rise to varying basal-plane contraction throughout the foil resulting in almost macroscopic (micron scale) deformation of the graphite. These observations are presented and discussed with a view to reconciling them with current understanding of point defect behavior in graphite.*Microscope and Ion Accelerator for Materials Investigations

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In Situ TEM Observations of Heavy Ion Damage in Gallium Arsenide

MRS Proceedings ◽

10.1557/proc-100-293 ◽

1988 ◽

Vol 100 ◽

Cited By ~ 4

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.

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Effects of krypton ion irradiation on the structure and morphology of germanium — An in situ TEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175818 ◽

1990 ◽

Vol 48 (4) ◽

pp. 536-537

Author(s):

L.M. Wang ◽

R.C. Birtcher

Keyword(s):

Ion Irradiation ◽

Morphological Changes ◽

Amorphous Material ◽

National Laboratory ◽

Argonne National Laboratory ◽

In Situ Tem ◽

Tandem Accelerator ◽

Accelerator Facility ◽

Voltage Electron

Although it was initially thought that irradiation could not further damage an amorphous material, an anomalous ion-induced morphological instability on the surface of amorphous Ge has been reported previously by several authors. In this study, the structural and morphological changes of Ge were monitored during 1.5 MeV Kr ion irradiation by in situ TEM to obtain insight into the damage evolution in ion-irradiated Ge.The in situ study was performed on the HVEM-Tandem Accelerator Facility at Argonne National Laboratory. The facility consists of a modified Kratos/AEI EM7 high voltage electron microscope (HVEM) and a 2 MV tandem ion accelerator. The samples were jet-polished polycrystalline Ge (99.99999 at. % pure) TEM discs with grain size > 5 μm in dimension. The Kr ion irradiation was carried out at room temperature, and the electron energy of the HVEM was 300 kV. According to a TRIM computer simulation, over 99% of the Kr ions penetrate through the electron transparent areas of the Ge sample, and a dose of 1×1015 Kr/cm2 created an average of ∽4 displacements per atom and an average Kr concentration of ∽12 appm in the observation region of the sample.

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Effets of surfaces on precipitate morphology in irradiated thin foils

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110416 ◽

1978 ◽

Vol 36 (1) ◽

pp. 654-655

Author(s):

D.I. Potter ◽

A. Taylor

Keyword(s):

Ion Irradiation ◽

Dark Field Image ◽

Thin Foil ◽

Dark Field ◽

Al Alloy ◽

Bright Field Image ◽

Dislocation Loops ◽

Precipitate Morphology ◽

Thin Foils

Thermal aging of Ni-12.8 at. % A1 and Ni-12.7 at. % Si produces spatially homogeneous dispersions of cuboidal γ'-Ni3Al or Ni3Si precipitate particles arrayed in the Ni solid solution. We have used 3.5-MeV 58Ni+ ion irradiation to examine the effect of irradiation during precipitation on precipitate morphology and distribution. The nearness of free surfaces produced unusual morphologies in foils thinned prior to irradiation. These thin-foil effects will be important during in-situ investigations of precipitation in the HVEM. The thin foil results can be interpreted in terms of observations from bulk irradiations which are described first.Figure 1a is a dark field image of the γ' precipitate 5000 Å beneath the surface(∿1200 Å short of peak damage) of the Ni-Al alloy irradiated in bulk form. The inhomogeneous spatial distribution of γ' results from the presence of voids and dislocation loops which can be seen in the bright field image of the same area, Fig. 1b.

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The Effect of Flux on Ion Irradiation-Induced Precipitation in AISI-316L: An In-Situ TEM Study

SSRN Electronic Journal ◽

10.2139/ssrn.3568079 ◽

2020 ◽

Author(s):

Ítalo M. Oyarzabal ◽

Matheus A. Tunes ◽

Osmane Camara ◽

Emily Aradi ◽

Anamul H. Mir ◽

...

Keyword(s):

Ion Irradiation ◽

In Situ Tem ◽

Aisi 316L

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In situ TEM thermal annealing of high purity Fe10wt%Cr alloy thin foils implanted with Ti and O ions

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/j.nimb.2019.10.009 ◽

2019 ◽

Vol 461 ◽

pp. 219-225

Author(s):

Martin Owusu-Mensah ◽

Stéphanie Jublot-Leclerc ◽

Aurélie Gentils ◽

Cédric Baumier ◽

Joël Ribis ◽

...

Keyword(s):

Thermal Annealing ◽

High Purity ◽

In Situ Tem ◽

Thin Foils

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In situ TEM observations of ion irradiation damage in boron carbide

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2018.11.011 ◽

2019 ◽

Vol 39 (4) ◽

pp. 726-734 ◽

Cited By ~ 4

Author(s):

Guillaume Victor ◽

Yves Pipon ◽

Nathalie Moncoffre ◽

Nicolas Bérerd ◽

Claude Esnouf ◽

...

Keyword(s):

Boron Carbide ◽

Ion Irradiation ◽

Irradiation Damage ◽

In Situ Tem

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In-Situ TEM Study of Plastic Stress Relaxation Mechanisms and Interface Effects in Metallic Films

MRS Proceedings ◽

10.1557/proc-875-o9.1 ◽

2005 ◽

Vol 875 ◽

Cited By ~ 6

Author(s):

Marc Legros ◽

Gerhard Dehm ◽

T. John Balk

Keyword(s):

Thin Films ◽

High Strength ◽

Dislocation Motion ◽

Dislocation Nucleation ◽

Film Stress ◽

In Situ Tem ◽

Metallic Films ◽

Cross Sectional ◽

Thin Foils

AbstractTo investigate the origin of the high strength of thin films, in-situ cross-sectional TEM deformation experiments have been performed on several metallic films attached to rigid substrates. Thermal cycles, comparable to those performed using laser reflectometry, were applied to thin foils inside the TEM and dislocation motion was recorded dynamically on video. These observations can be directly compared to the current models of dislocation hardening in thin films. As expected, the role of interfaces is crucial, but, depending on their nature, they can attract or repel dislocations. When the film/interface holds off dislocations, experimental values of film stress match those predicted by the Nix-Freund model. In contrast, the attracting case leads to higher stresses that are not explained by this model. Two possible hardening scenarios are explored here. The first one assumes that the dislocation/interface attraction reduces dislocation mobility and thus increases the yield stress of the film. The second one focuses on the lack of dislocation nucleation processes in the case of attracting interfaces, even though a few sources have been observed in-situ.

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Amorphization Kinetics of Zr (Cr,Fe)2 Under Ion Irradiation

MRS Proceedings ◽

10.1557/proc-279-517 ◽

1992 ◽

Vol 279 ◽

Cited By ~ 4

Author(s):

A. T. Motta ◽

L. M. Howe ◽

P. R. Okamoto

Keyword(s):

Neutron Irradiation ◽

Ion Irradiation ◽

Ion Beam ◽

National Laboratory ◽

Argonne National Laboratory ◽

Matrix Interface ◽

Thin Foils ◽

Intermetallic Precipitates ◽

Kinetics Of

ABSTRACTThin foils of Zircaloy-4 were irradiated with 350 KeV 40Ar ions in the dual ion beam/HVEM facility at Argonne National Laboratory at 300 – 650 K. The irradiation-induced araorphization of the intermetallic precipitates Zr (Cr, Fe)2 and Zr2 (Ni, Fe) was studied in situ. For Zr (Cr,Fe)2 precipitates the dose-to-amorphization was found to increase exponentially with temperature, with a critical temperature of about 650 K. The amorphization morphology was shown to be homogeneous, with no preferential site for nucleation, in contrast to neutron-irradiation amorphization which started at the precipitate-matrix interface. For Zr2 (Ni,Fe) precipitates it was found that amorphization occurred at 550 K and 600 K, whereas in neutron irradiation no amorphization has been observed at those temperatures. The results are discussed in the context of the previous experimental results of neutron and electron irradiation and likely amorphization mechanisms are proposed.

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