Correlating Atom Probe Crystallographic Measurements with Transmission Kikuchi Diffraction Data

2017 ◽  
Vol 23 (2) ◽  
pp. 279-290 ◽  
Author(s):  
Andrew J. Breen ◽  
Katharina Babinsky ◽  
Alec C. Day ◽  
K. Eder ◽  
Connor J. Oakman ◽  
...  
Keyword(s):  
Atom Probe Tomography ◽  
Angular Resolution ◽  
Atom Probe ◽  
Correlative Microscopy ◽  
Alloy Specimen ◽  
Experimental Conditions ◽  
Research Problems ◽  
Engineering Alloys ◽  
Microscopy Techniques ◽  
First Time

AbstractCorrelative microscopy approaches offer synergistic solutions to many research problems. One such combination, that has been studied in limited detail, is the use of atom probe tomography (APT) and transmission Kikuchi diffraction (TKD) on the same tip specimen. By combining these two powerful microscopy techniques, the microstructure of important engineering alloys can be studied in greater detail. For the first time, the accuracy of crystallographic measurements made using APT will be independently verified using TKD. Experimental data from two atom probe tips, one a nanocrystalline Al–0.5Ag alloy specimen collected on a straight flight-path atom probe and the other a high purity Mo specimen collected on a reflectron-fitted instrument, will be compared. We find that the average minimum misorientation angle, calculated from calibrated atom probe reconstructions with two different pole combinations, deviate 0.7° and 1.4°, respectively, from the TKD results. The type of atom probe and experimental conditions appear to have some impact on this accuracy and the reconstruction and measurement procedures are likely to contribute further to degradation in angular resolution. The challenges and implications of this correlative approach will also be discussed.

scholarly journals Impact of the Co/Ni-Ratio on Microstructure, Thermophysical Properties and Creep Performance of Multi-Component γ′-Strengthened Superalloys

Crystals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1058
Author(s):  
Christopher H. Zenk ◽  
Nicklas Volz ◽  
Carolin Zenk ◽  
Peter J. Felfer ◽  
Steffen Neumeier
Keyword(s):  
Atom Probe Tomography ◽  
Lattice Misfit ◽  
Microstructural Characterization ◽  
Atom Probe ◽  
Creep Tests ◽  
Ni Content ◽  
Rich Alloy ◽  
First Time ◽  
Partitioning Behavior

The Ni content is a crucial factor for the development of γ′-strengthened Co-based superalloys and some studies have systematically addressed its influence on various properties in model superalloys. In this paper, we report for the first time the influence of the Co/Ni ratio in the more advanced nine-component superalloy ERBOCo-1: exchanging Co and Ni in this Co/Ni-based superalloy while keeping the other alloying elements constants has a big influence on a variety of material properties. The elemental segregation after casting is slightly more pronounced in the alloy with higher Ni-content. Microstructural characterization of this alloy termed ERBOCo-1X after heat-treatment reveals that the precipitates are cuboidal in the Co- and spherical in the Ni-rich alloy, indicating a decrease in the γ/γ′ lattice misfit. Analyzing the elemental partitioning behavior by atom probe tomography suggests that the partitioning behavior of W is responsible for that. Furthermore, it is found that even though Ni exhibits the highest overall concentration, the γ matrix phase is still Co-based, because Ni is strongly enriched in the γ′ precipitates. Creep tests at 900 °C reveal that even though the microstructure looks less favorable, the creep resistance of the Ni-rich alloy is slightly superior to the Co-rich variant.

Quantitative Analysis of Precipitate Compositions in an Al-Li-Mg-Cu Alloy Using Atom Probe Tomography

2010 ◽  
Vol 654-656 ◽  
pp. 914-917 ◽  
Author(s):  
Xiang Yuan Xiong ◽  
Stavroula Moutsos ◽  
Russell King ◽  
Barry C. Muddle
Keyword(s):  
Quantitative Analysis ◽  
Aluminium Alloy ◽  
Atom Probe Tomography ◽  
Lithium Concentration ◽  
Stoichiometric Composition ◽  
Atom Probe ◽  
Field Evaporation ◽  
Experimental Conditions ◽  
3 Dimensional ◽  
Cu Alloy

The composition of  precipitates in aluminium alloy 8090 has been analysed using a 3 dimensional atom probe with fast data acquisition rates. The effects of experimental conditions for the quantitative atom probe analysis have been examined in detail. The results show that i) lithium is prone to preferential DC field evaporation at temperatures > 25K and with a pulse fraction < 20%; ii) the lithium concentration of  precipitates can vary from precipitate to precipitate, ranging from 19.1 to 25.3 at.%, and iii) the stoichiometric composition of the  phase can be obtained provided that the probing temperature is  25K and pulse fraction is  20%.

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

Field-Dependent Measurement of GaAs Composition by Atom Probe Tomography

2017 ◽  
Vol 23 (6) ◽  
pp. 1067-1075 ◽  
Author(s):  
Enrico Di Russo ◽  
Ivan Blum ◽  
Jonathan Houard ◽  
Gérald Da Costa ◽  
Didier Blavette ◽  
...  
Keyword(s):  
Atom Probe Tomography ◽  
High Field ◽  
Laser Energy ◽  
Atom Probe ◽  
Major Influence ◽  
Atomic Fraction ◽  
Compositional Bias ◽  
Experimental Conditions ◽  
Preferential Evaporation ◽  
Large Clusters

AbstractThe composition of GaAs measured by laser-assisted atom probe tomography may be inaccurate depending on the experimental conditions. In this work, we assess the role of the DC field and the impinging laser energy on such compositional bias. The DC field is found to have a major influence, while the laser energy has a weaker one within the range of parameters explored. The atomic fraction of Ga may vary from 0.55 at low-field conditions to 0.35 at high field. These results have been interpreted in terms of preferential evaporation of Ga at high field. The deficit of As is most likely explained by the formation of neutral As complexes either by direct ejection from the tip surface or upon the dissociation of large clusters. The study of multiple detection events supports this interpretation.

scholarly journals Экспериментально-теоретическое исследование эволюции атомной структуры высокоэнтропийных сплавов на основе Fe, Cr, Ni, Mn и Co при термическом и радиационном старении

2020 ◽  
Vol 62 (3) ◽  
pp. 339
Author(s):  
Е.А. Мешков ◽  
И.И. Новоселов ◽  
А.В. Янилкин ◽  
С.В. Рогожкин ◽  
А.А. Никитин ◽  
...  
Keyword(s):  
Atom Probe Tomography ◽  
Theoretical Study ◽  
Atom Probe ◽  
Quantum Mechanical ◽  
Atomistic Modeling ◽  
Modeling Methods ◽  
Local Ordering ◽  
Initial Stage ◽  
Cocrfeni Alloy ◽  
First Time

The comprehensive experimental and theoretical study of the processes of local ordering of multicomponent alloys was carried out. Experimental techniques included atom-probe tomography and measurement of electrical resistivity during isochronal annealing. The theoretical study was carried out by atomistic modeling methods. The evolution of the system was described in the framework of the multiscale paradigm which is based on quantum-mechanical calculations. The initial stage of the decomposition of a solid solution of CoCrFeNi alloy with the formation of Ni4Cr and Ni2Cr precipitations was demonstrated for the first time by the employed approach.

scholarly journals Atomically resolved calcium phosphate coating on a gold substrate

Nanoscale ◽  
2018 ◽  
Vol 10 (18) ◽  
pp. 8451-8458 ◽  
Author(s):  
Noah Metoki ◽  
Sung-Il Baik ◽  
Dieter Isheim ◽  
Daniel Mandler ◽  
David N. Seidman ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Calcium Phosphate ◽  
Atom Probe Tomography ◽  
Atom Probe ◽  
Calcium Phosphate Coating ◽  
Phosphate Coating ◽  
Gold Substrate ◽  
Transmission Electron ◽  
First Time

Electrodeposited calcium phosphate is studied for the first time by atom-probe tomography. Combined with transmission electron microscopy, ACP, DCPD and OCP phases are identified unambiguously at the heterophase interface. These phases could all serve as transient precursor phases to hydroxyapatite (HAp).

scholarly journals Nanoscale Stoichiometric Analysis of a High-Temperature Superconductor by Atom Probe Tomography

2017 ◽  
Vol 23 (2) ◽  
pp. 414-424 ◽  
Author(s):  
Stella Pedrazzini ◽  
Andrew J. London ◽  
Baptiste Gault ◽  
David Saxey ◽  
Susannah Speller ◽  
...  
Keyword(s):  
High Temperature ◽  
Atom Probe Tomography ◽  
High Temperature Superconductor ◽  
Analytical Techniques ◽  
Atom Probe ◽  
Three Dimensions ◽  
Oxygen Stoichiometry ◽  
Superconducting Properties ◽  
Experimental Conditions ◽  
Wide Range

AbstractThe functional properties of the high-temperature superconductor Y1Ba2Cu3O7−δ(Y-123) are closely correlated to the exact stoichiometry and oxygen content. Exceeding the critical value of 1 oxygen vacancy for every five unit cells (δ>0.2, which translates to a 1.5 at% deviation from the nominal oxygen stoichiometry of Y7.7Ba15.3Cu23O54−δ) is sufficient to alter the superconducting properties. Stoichiometry at the nanometer scale, particularly of oxygen and other lighter elements, is extremely difficult to quantify in complex functional ceramics by most currently available analytical techniques. The present study is an analysis and optimization of the experimental conditions required to quantify the local nanoscale stoichiometry of single crystal yttrium barium copper oxide (YBCO) samples in three dimensions by atom probe tomography (APT). APT analysis required systematic exploration of a wide range of data acquisition and processing conditions to calibrate the measurements. Laser pulse energy, ion identification, and the choice of range widths were all found to influence composition measurements. The final composition obtained from melt-grown crystals with optimized superconducting properties was Y7.9Ba10.4Cu24.4O57.2.

Effect of Trace Addition of Sn in Al-Cu Alloy

2006 ◽  
Vol 519-521 ◽  
pp. 203-208 ◽  
Author(s):  
Tomoyuki Honma ◽  
David W. Saxey ◽  
Simon P. Ringer
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Microscope ◽  
Atom Probe Tomography ◽  
Atom Probe ◽  
Cu Alloy ◽  
Trace Addition ◽  
Transmission Electron ◽  
Decomposition Processes ◽  
First Time

The trace addition of Sn (0.01 at.%) to an Al-1.7Cu (at.%) alloy has been investigated using atom probe tomography (APT), transmission electron microscopy (TEM) and high resolution transmission electron microscope (HRTEM). We have studied samples in the as-quenched (AQ) condition and following ageing at both 160 and 200 °C for very short ageing times so as to better understand the early stages of the decomposition processes. Our data reveal independent Cu-Cu and Sn-Sn clusters in the AQ condition, though we did not observe Cu-Sn clustering. We observed for the first time that some of these initial Cu-clusters develop into GP zones during subsequent ageing at temperatures as high as 200 °C. The Sn atom clustering results in precipitation of independent 􀀂- Sn particles after aging for 30 sec. The GP zones consequently undergo reversion and this liberates Cu atoms which seem to participate in a cluster-assisted heterogeneous nucleation of the 􀀃􀀂 phase at the interface of the 􀀂-Sn. For ageing at 200 °C, this process is complete within 180 sec.

Sign in / Sign up

Export Citation Format

Share Document