scholarly journals Combined Atom-Probe and Electron Microscopy Characterization of Fine Scale Structures in Aged Primary Coolant Pipe Stainless Steel

1986 ◽  
Vol 82 ◽  
Author(s):  
J. Bentley ◽  
M. K. Miller
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Atom Probe ◽  
Primary Coolant ◽  
Probe Field ◽  
Α Phase ◽  
Complementary Nature ◽  
Microscopy Characterization

ABSTRACTThe capabilities and complementary nature of atom probe field-ion microscopy (APFIM) and analytical electron microscopy (AEM) for the characterization of finescale microstructures are illustrated by examination of the changes that occur after long term thermal aging of cast CF 8 and CF 8M duplex stainless steels. In material aged at 300 or 400°C for up to 70,000 h, the ferrite had spinodally decomposed into a modulated fine-scaled interconnected network consisting of an iron-rich α′ phase and a chromium-enriched α phase with periodicities of between 2 and 9 nm. G-phase precipitates 2 to 10 nm in diameter were also observed in the ferrite at concentrations of more than 1021 m−3. The reported degradation in mechanical properties is most likely a consequence of the spinodal decomposition in the ferrite.

Analytical ELectron Microscopy Characterization of Basalt Glass Ceramics

1982 ◽  
Vol 40 ◽  
pp. 616-617
Author(s):  
L. E. Thomas ◽  
L. A. Chick ◽  
R. O. Lokken
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Glass Ceramics ◽  
Ceramic Materials ◽  
Basalt Glass ◽  
Glass Ceramic Materials ◽  
Analytical Electron ◽  
Microscopy Characterization

Radioactive waste produced by nuclear reactors poses long term environmental hazards if not adequately immobilized and stored. As part of a program for developing basalt-based waste forms with high leach durability, analytical electron microscopy has been used to identify and chemically analyze the phases in several basalt glass/ceramic materials.

Origin and Influence of Pre-Existing Segregation on Radiation-Induced Segregation In Austenitic Stainless Steels

1998 ◽  
Vol 540 ◽  
Author(s):  
E. A. Kenik ◽  
J. T. Busby ◽  
M. K. Miller ◽  
A. M. Thuvander ◽  
G. Was
Keyword(s):  
Electron Microscopy ◽  
Grain Boundaries ◽  
Stainless Steels ◽  
Analytical Electron Microscopy ◽  
Austenitic Stainless Steels ◽  
Atom Probe ◽  
Molecular Ions ◽  
Probe Field ◽  
Analytical Electron ◽  
Radiation Induced

AbstractThe pre-existing segregation at grain boundaries in two austenitic stainless steels has been investigated by atom probe field ion microscopy and analytical electron microscopy. In addition, the effect of radiation-induced segregation on the near-grain-boundary composition has been studied by analytical electron microscopy. Pre-existing enrichment of Cr, Mo, B, C and P and depletion of Fe and Ni near grain boundaries has been observed. Significant affinity between Mo and N in both alloys is indicated by the detection of MoN2+` molecular ions during field evaporation. The pre-existing segregation is modified by radiation-induced segregation resulting in Ni and Si enrichment near the boundary as well as depletion of chromium adjacent to the boundary resulting in a “W-shaped” Cr profile.

scholarly journals Characterization of Ni-base Superalloys on the Atomic Scale by Atom Probe Tomography and Spherical-Aberration Corrected Analytical Electron Microscopy Techniques

2006 ◽  
Vol 12 (S02) ◽  
pp. 534-535 ◽  
Author(s):  
M Watanabe ◽  
D Saxey ◽  
R Zheng ◽  
D Williams ◽  
S Ringer
Keyword(s):  
Electron Microscopy ◽  
Atom Probe Tomography ◽  
Spherical Aberration ◽  
Analytical Electron Microscopy ◽  
Atom Probe ◽  
Atomic Scale ◽  
Analytical Electron ◽  
Microscopy Techniques ◽  
Aberration Corrected

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006

scholarly journals Analytical Electron Microscopy Characterization of a Temperature-Stable Relaxor Ferroelectric Ceramic

2019 ◽  
Vol 25 (S2) ◽  
pp. 2118-2119
Author(s):  
Teresa Roncal-Herrero ◽  
John Harrington ◽  
Aurang Zeb ◽  
Steven J Milne ◽  
Andy P. Brown
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Ferroelectric Ceramic ◽  
Relaxor Ferroelectric ◽  
Analytical Electron ◽  
Microscopy Characterization

A combined AEM/APFIM characterization of alloy X-750

1992 ◽  
Vol 50 (1) ◽  
pp. 174-175
Author(s):  
M.G. Burke ◽  
M.K. Miller
Keyword(s):  
Mechanical Properties ◽  
Analytical Electron Microscopy ◽  
Atom Probe ◽  
Alloy Development ◽  
Probe Field ◽  
Surrounding Matrix ◽  
The Matrix ◽  
Size And Morphology ◽  
Field Ion Microscope

In the development of advanced alloys for power system applications, the primary emphasis is placed on attaining specific mechanical properties with resistance to environmental attack. An important part of alloy development is the detailed characterization of the microstructure, because it is the composition, size and morphology of the microstructural features that define the mechanical properties of the material. The good mechanical properties of Ni-base superalloys are a result of the formation of fine coherent precipitates. In addition, other coarser phases may form which can degrade the properties of the alloys. Analytical electron microscopy (AEM) provides important information concerning the type and distribution of the phases in the alloys, but quantitative microchemical analysis of the ultra-fine precipitates is not readily obtainable with conventional AEM techniques. The high spatial resolution of the atom probe field-ion microscope (APFIM) makes this technique ideally suited to the analysis of the ultra-fine precipitates and surrounding matrix. The analysis of the matrix is particularly important in predicting the subsequent ageing response of the alloy, as previously shown in a detailed AEM/APFIM examination of Alloy 718. In this paper, a combined AEM/APFIM study of precipitation in Alloy X-750 is presented.

Identification Of G-Phase In Aged Cast CF 8 Type Stainless Steel

1985 ◽  
Vol 43 ◽  
pp. 328-329 ◽  
Author(s):  
J. Bentley ◽  
M. K. Miller ◽  
S. S. Brenner ◽  
J. A. Spitznagel
Keyword(s):  
Stainless Steel ◽  
Nuclear Reactors ◽  
Analytical Electron Microscopy ◽  
Atom Probe ◽  
Duplex Structure ◽  
Primary Coolant ◽  
Probe Field ◽  
Aged Material ◽  
Type Stainless Steel ◽  
Analytical Electron

The microstructure of as-cast and aged CF 8 type stainless steel, used for the primary coolant pipes in pressurized light-water nuclear reactors, is being studied by analytical electron microscopy (AEM) and atom probe field-ion microscopy (APFIM). The phase transformations of the ferrite (∼19 vol % of the duplex structure) that occur after aging at 673 K for 7500 h are described by Miller et al. The present work deals with the identification of G-phase (prototype compound Ni16Ti6Si7) observed in the ferrite of aged material.In FIM images the precipitates had bright contrast, appeared roughly spherical, were ∼10 nm in diameter, and were present at a concentration of ∼1023 m-3. Atom probe selected area microchemical analyses of the central portion of five precipitates revealed that they were alloy silicides, Table 1.

Characterizatiom of spinodally decomposed Fe-30.1% Cr-9.9% Co: Part 1

1986 ◽  
Vol 44 ◽  
pp. 580-581
Author(s):  
L. L. Horton ◽  
M. K. Miller ◽  
S. Spooner
Keyword(s):  
Isothermal Aging ◽  
Small Angle Neutron Scattering ◽  
Atom Probe ◽  
Probe Field ◽  
Solution Treated ◽  
Transmission Electron ◽  
Water Quench ◽  
Complementary Nature ◽  
Ion Microscopy

Transmission Electron Microscopy (TEM), Atom Probe Field-Ion Microscopy (APFIM) and Small Angle Neutron Scattering (SANS) have been used to characterize the microstructure of a commercial Fe-30.1 at.% Cr-9.9 at.% Co alloy. One goal of this investigation was to demonstrate the complementary nature of these techniques in solving a difficult materials problem, the characterization of fine scale spinodally-decomposed structures. The alloy was solution treated at 925°C for 140 min followed by water quenching, isothermal aging at 525°C for times of 2, 8, 24, 72, 192, or 485 h and a final water quench. TEM characterizations were performed with Philips EM400T/FEG, Philips EM430T and JEM 120C instruments.

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