Physical Testing and Surface Morphology Studies of Stainless Steel Irradiated with Xe Ions

Abstract 6 MeV Xe ions were used to irradiate austenitic stainless steel at room temperature. Three displacement damage levels of 2,7 and 15 dpa were selected. Microstructure and surface morphology were characterized by transmission electron microscopy (TEM), positron annihilation lifetime spectroscopy (PLS) and atomic force microscope (AFM). PLS indicated that vacancy defects were introduced by ions irradiation. Vacancy clusters containing Xe will reduce the positron annihilation lifetime. High density of dislocation loops were observed by TEM. The dislocation loops size and density saturates after 7 dpa and the nature of dislocation loops can be deduced by its distribution. A surface step was detected by AFM measurements between irradiated region (uncovered) and unirradiated region (covered with nickel mesh). This indicate that the irradiation swelling phenomenon occur and swelling is closely related to irradiation damage. According to the step height, the volume swelling is about 1.7% and 4.2% after irradiated to 7 and 15 dpa.

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Characterization of neutron irradiation damage in zirconium alloys—an international “round-robin” experiment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108970 ◽

1978 ◽

Vol 36 (1) ◽

pp. 366-367

Author(s):

D.O. Northwood ◽

R.W. Gilbert ◽

P.M. Kelly ◽

P.K. Madden ◽

D. Faulkner ◽

...

Keyword(s):

Zirconium Alloys ◽

Round Robin ◽

Irradiation Damage ◽

Exact Nature ◽

Dislocation Loops ◽

The Past ◽

Irradiation Growth ◽

Transmission Electron ◽

International Round

Over the past few years there has been disagreement between laboratories on the exact nature of the damage in irradiated zirconium alloys. The main disagreement has centred on whether or not dislocation loops with c-component Burgers' vectors are formed during the irradiation. Since the presence of c-component loops was required in one of the current theories of irradiation growth and is considered in many other models, it was desirable to clear up this point and others relating to the nature of the damage such as loop size, loop concentration and the nature of the loop population, i.e. vacancy or interstitial. To this end a ‘round-robin’ series of transmission electron microscopy (TEM) examinations of neutron irradiated zirconium alloys was organized and the results are reported herein.The participants in the ‘round-robin’ included laboratories who had previously claimed to have seen evidence for c-component damage. The materials examined included zirconium and Zircaloy-2 irradiated at temperatures from 250-400°C, Table 1, the materials irradiated at 400°C providing samples with dislocation loops large enough to determine the interstitial/vacancy nature by inside/outside contrast techniques.

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Vacancy-Assisted Precipitation in a 18 W/O Cr - 10 W/O ni - 0.3 W/O P Steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098174 ◽

1981 ◽

Vol 39 ◽

pp. 332-333

Author(s):

A. R. Pelton

Keyword(s):

Stainless Steel ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Austenitic Steels ◽

Orientation Relationships ◽

Precipitation Behavior ◽

Vacancy Defects ◽

Transmission Electron ◽

Nucleation And Growth Mechanisms ◽

Habit Planes

Although many similarities exist in the precipitation behavior in ferritic and austenitic steels, the nucleation and growth mechanisms in these systems have eluded full comprehension. However, it is apparent that the initial clustering of substitutional and interstitial atoms can dictate the structure and orientation relationships of subsequent phases. Hence, in order to realize the benefits of these decomposition transformations, a better understanding of the incipient nucleation event is imperative. Therefore, a transmission electron microscopy study of a quenched-aged 18-10 stainless steel doped with 0.3 w/o P was undertaken as part of a more comprehensive research program. The precipitation reactions in this austenitic stainless steel were originally surveyed by Rowcliffe and Nicholson [1] and Rowcliffe and Eyre [2], These investigators observed a variety of defects ranging from vacancy defects on {100} planes at lower aging temperatures to Cr3P laths with {100} habit planes at higher aging temperatures.

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Epitaxial growth and surface morphology of aluminum films deposited on mica studied by transmission electron microscopy and atomic force microscopy

Thin Solid Films ◽

10.1016/j.tsf.2007.04.046 ◽

2007 ◽

Vol 516 (1) ◽

pp. 17-24 ◽

Cited By ~ 17

Author(s):

Morihide Higo ◽

Katsuya Fujita ◽

Masaru Mitsushio ◽

Toshifumi Yoshidome ◽

Terumi Kakoi

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Atomic Force Microscopy ◽

Surface Morphology ◽

Epitaxial Growth ◽

Aluminum Films ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron

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Surface Morphology of SiGe Epitaxial Layers Grown on Uniquely Oriented Si Substrates

MRS Proceedings ◽

10.1557/proc-648-p10.8 ◽

2000 ◽

Vol 648 ◽

Author(s):

Morgan E. Ware ◽

Robert J. Nemanich

Keyword(s):

Surface Morphology ◽

Lattice Mismatch ◽

Morphological Structure ◽

Epitaxial Layers ◽

Misfit Dislocations ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force ◽

Transmission Electron ◽

Relationship Of

AbstractThe 4% lattice mismatch between Si and Ge creates strain in epitaxial layers of SiGe alloys on Si, and this strain can manifest itself in the morphological structure of the surface of the epitaxial layer. This study explores the relationship of the evolution of the surface morphology of SiGe layers grown on a range of Si surface orientations. We have grown thin, strained and thick, relaxed layers of Si0.7Ge0.3 by solid source molecular beam epitaxy on substrates with surface normals rotated from [001] towards [111] by angles of θ = (0, 2, 4, 10, 22) degrees. The surface morphology was investigated by atomic force microscopy, which showed considerable ordering of surface features on relaxed samples. These features evolve from hut-like structures at 0 degrees to large mesa-like structures separated by pits and crevices at 22 degrees. The organization of these features is also shown to vary with the substrate orientation. Each surface has characteristic directions along which features are aligned, and these directions vary continuously with the angle of rotation of the substrate. Transmission electron microscopy confirmed that misfit dislocations had formed along those same directions. The state of relaxation of each layer is quantified by Raman spectroscopy in order to make a direct correlation between residual strain and surface morphology.

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Surface Roughening and Composition Modulation of ZnSe-related II-VI epitaxial films

MRS Proceedings ◽

10.1557/proc-448-159 ◽

1996 ◽

Vol 448 ◽

Cited By ~ 2

Author(s):

Shigetaka Tomiya ◽

Hironori Tsukamoto ◽

Satoshi Itoh ◽

Kazushi Nakano ◽

Etsuo Morita ◽

...

Keyword(s):

Surface Morphology ◽

Surface Reconstruction ◽

Epitaxial Films ◽

Surface Roughening ◽

Force Microscopy ◽

Composition Modulation ◽

Atomic Force ◽

Transmission Electron ◽

Rich Condition ◽

Lattice Matched

AbstractWe have investigated ZnSSe and ZnMgSSe epitaxial layers lattice-matched to GaAs (001) substrates grown by molecular beam epitaxy using atomic force microscopy and transmission electron microscopy. Under II-rich conditions with c(2x2) surface reconstruction, surface morphology exhibited corrugation aligned in the [1ī0] direction and composition modulation was observed in the same [1ī0] direction. Under VI-rich condition with (2x1) surface reconstruction, the surface morphology becomes rounded grain-like and composition modulation was not observed. The formation of composition modulation is associated with the surface corrugated structures.

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Study of Interaction Mechanism between Positrons and Ag Clusters in Dilute Al–Ag Alloys at Low Temperature

Materials ◽

10.3390/ma14061451 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1451

Author(s):

Xiaoshuang Liu ◽

Peng Zhang ◽

Baoyi Wang ◽

Xingzhong Cao ◽

Shuoxue Jin ◽

...

Keyword(s):

Positron Annihilation ◽

Low Temperatures ◽

Interaction Mechanism ◽

Doppler Broadening ◽

Positron Annihilation Lifetime ◽

Transmission Electron ◽

Combined Use ◽

Calculation Results ◽

Ag Clusters ◽

Aging Stage

The microstructural evolution of dilute Al–Ag alloys in its early aging stage and at low temperatures ranging from 15 K to 300 K was studied by the combined use of Positron annihilation lifetime spectroscopy (PALS), high resolution transmission electron microscopy (HRTEM), and positron annihilation Coincidence Doppler broadening (CDB) techniques. It is shown that at low temperatures below 200 K, an Ag–vacancy complex is formed in the quenched alloy, and above 200 K, it decomposes into Ag clusters and monovacancies. Experimental and calculation results indicate that Ag clusters in Al–Ag alloys can act as shallow trapping sites, and the positron trapping rate is considerably enhanced by a decreasing measurement temperature.

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Variable Energy Positron Annihilation Spectroscopy of Perovskite Oxides

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.331.201 ◽

2012 ◽

Vol 331 ◽

pp. 201-233 ◽

Cited By ~ 1

Author(s):

David J. Keeble

Keyword(s):

Positron Annihilation ◽

Oxygen Deficiency ◽

Single Layer ◽

Positron Annihilation Spectroscopy ◽

Perovskite Oxide ◽

Near Surface ◽

Vacancy Defects ◽

Positron Annihilation Lifetime ◽

Primary Focus ◽

Variable Energy

The application of variable energy positron annihilation spectroscopy (VE-PAS) methods to the study of perovskite oxide, ABO3, material thin films and near-surface regions is reviewed. The primary focus is on ferroic perovskite titanate oxide materials SrTiO3and Pb (ZrxTi1-x)O3, but studies of BaTiO3, LaxSr1-xCoO3, La0.67Sr0.33MnO3and YBa2CuO7-δare also included. Characterization of single layer and multilayer structures is discussed. The methods, in particular positron annihilation lifetime spectroscopy, allow the identification of cation vacancy defects at both the A-and B-sites with parts per million sensitivity. Varying oxygen deficiency is often observed to result in marked changes in PAS spectra; these effects are reviewed and discussed.

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Oxidation behavior of TiN with a Ti interlayer on stainless steel

MRS Proceedings ◽

10.1557/proc-819-n3.2 ◽

2004 ◽

Vol 819 ◽

Author(s):

Ming-Hua Shiao ◽

Ching-Chiun Wang ◽

Chien-Ying Su ◽

Fuh-Sheng Shieu

Keyword(s):

Stainless Steel ◽

Steel Substrate ◽

Depth Profiling ◽

Columnar Structure ◽

304 Stainless Steel ◽

Force Microscopy ◽

Tin Coatings ◽

Atomic Force ◽

Transmission Electron ◽

Tin Thin Films

AbstractCharacterization of the TiN coatings oxidized in air at temperatures at 600 and 700°C for 30 min was carried out by X-ray diffraction (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM) and Auger electron spectroscopy (AES). TiN thin films with a Ti interlayer were prepared by hollow cathode discharge ion plating on AISI 304 stainless steel. Both XRD and TEM results show that the TiN coatings and Ti interlayer have columnar structure with (111) and (0002) preferred orientations, respectively. AFM results show the existence of pinholes on the surface of specimens due to electropolishing process of the steel substrate, and the surface roughness (Ra) changes from 3.5 nm for the as-deposited specimen to 11.6 nm after oxidation at 700°. After oxidation, the TiO2 oxide layer formed on the specimen surface was porous and retained the columnar structure as the original TiN coating. The microstructure of the Ti interlayer gradually changed from columnar to polycrystalline structure due to grain growth. The Auger elemental depth profiling indicated that interdiffusion of the Ti interlayer with steel substrate had occurred during the oxidation process.

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