Julie Cairney | The University of Sydney (original) (raw)

Papers by Julie Cairney

Research paper thumbnail of Effect of ion irradiation on tensile ductility, strength and fictive temperature in metallic glass nanowires

Research paper thumbnail of Site-specific specimen preparation for atom probe tomography of grain boundaries

Physica B Condensed Matter

Atom probe tomography is a powerful technique that is highly suited to the study of low-level gra... more Atom probe tomography is a powerful technique that is highly suited to the study of low-level grain boundary segregation. However, difficulties in preparation of the required needle-shaped specimens containing the area of interest have precluded detailed studies of this nature to date. Two new methods are presented to manufacture atom probe tips from site-specific areas using a dual-beam focused ion beam (FIB)/scanning electron microscope (SEM). One involves the use of electropolished blanks, which are resharpened using the ion beam, and the second utilises micromanipulators to lift the area of interest directly from a bulk specimen before ion beam fabrication of the tip. The advantages and drawbacks of each technique are compared.

Research paper thumbnail of Atom probe specimen fabrication methods using a dual FIB/SEM

Ultramicroscopy

A dual FIB/SEM provides solutions to many challenges in atom probe specimen preparation. When com... more A dual FIB/SEM provides solutions to many challenges in atom probe specimen preparation. When combined with an in situ lift-out capability, the versatility of this tool allows almost any region of interest, in almost any geometry, to be placed at the apex of a specimen tip. Several preparation techniques have been developed in response to specific application requirements; for example, in cases where materials are not suitable for electropolishing, or where site-specific analysis is required. Two general techniques, with wide-ranging potential applications, are described in detail here. The first is a 'cut-out' technique that provides a relatively quick means of micro-tip specimen preparation from bulk material samples. The second method is a 'lift-out' technique that can be used in an in situ or ex situ mode and does not require the preparation of pre-sharpened mounting points.

Research paper thumbnail of Recent Advances in FIB-based Site-specific Atom Probe Specimen Preparation Techniques

Microscopy and Microanalysis

Research paper thumbnail of New atom probe approaches to studying segregation in nanocrystalline materials

Ultramicroscopy

Atom probe is a technique that is highly suited to the study of nanocrystalline materials. It can... more Atom probe is a technique that is highly suited to the study of nanocrystalline materials. It can provide accurate atomic-scale information about the composition of grain boundaries in three dimensions. In this paper we have analysed the microstructure of a nanocrystalline super-duplex stainless steel prepared by high pressure torsion (HPT). Not all of the grain boundaries in this alloy display obvious segregation, making visualisation of the microstructure challenging. In addition, the grain boundaries present in the atom probe data acquired from this alloy have complex shapes that are curved at the scale of the dataset and the interfacial excess varies considerably over the boundaries, making the accurate characterisation of the distribution of solute challenging using existing analysis techniques. In this paper we present two new data treatment methods that allow the visualisation of boundaries with little or no segregation, the delineation of boundaries for further analysis and ...

Research paper thumbnail of Mining information from atom probe data

Research paper thumbnail of The effect orientation of features in reconstructed atom probe data on the resolution and measured composition of T1 plates in an A2198 aluminium alloy

Ultramicroscopy, Jan 14, 2015

Artefacts in atom probe tomography can impact the compositional analysis of microstructure in ato... more Artefacts in atom probe tomography can impact the compositional analysis of microstructure in atom probe studies. To determine the integrity of information obtained, it is essential to understand how the positioning of features influences compositional analysis. By investigating the influence of feature orientation within atom probe data on measured composition in microstructural features within an AA2198 Al alloy, this study shows differences in the composition of T1 (Al2CuLi) plates that indicates imperfections in atom probe reconstructions. The data fits a model of an exponentially-modified Gaussian that scales with the difference in evaporation field between solutes and matrix. This information provides a guide for obtaining the most accurate information possible.

Research paper thumbnail of Cover Picture: Revealing the Distribution of the Atoms within Individual Bimetallic Catalyst Nanoparticles (Angew. Chem. Int. Ed. 42/2014)

Angewandte Chemie International Edition, 2014

ABSTRACT To be able to correlate the catalytic properties of nanoparticles with their structure, ... more ABSTRACT To be able to correlate the catalytic properties of nanoparticles with their structure, detailed knowledge about their make-up on the atomic level is required. Herein, we demonstrate how atom-probe tomography (APT) can be used to quantitatively determine the three-dimensional distribution of atoms within a Au@Ag nanoparticle with near-atomic resolution. We reveal that the elements are not evenly distributed across the surface and that this distribution is related to the surface morphology and residues from the particle synthesis.

Research paper thumbnail of Titelbild: Revealing the Distribution of the Atoms within Individual Bimetallic Catalyst Nanoparticles (Angew. Chem. 42/2014)

Angewandte Chemie, 2014

ABSTRACT To be able to correlate the catalytic properties of nanoparticles with their structure, ... more ABSTRACT To be able to correlate the catalytic properties of nanoparticles with their structure, detailed knowledge about their make-up on the atomic level is required. Herein, we demonstrate how atom-probe tomography (APT) can be used to quantitatively determine the three-dimensional distribution of atoms within a Au@Ag nanoparticle with near-atomic resolution. We reveal that the elements are not evenly distributed across the surface and that this distribution is related to the surface morphology and residues from the particle synthesis.

Research paper thumbnail of A new systematic framework for crystallographic analysis of atom probe data

Ultramicroscopy, Jan 18, 2015

In this article, after a brief introduction to the principles behind atom probe crystallography, ... more In this article, after a brief introduction to the principles behind atom probe crystallography, we introduce methods for unambiguously determining the presence of crystal planes within atom probe datasets, as well as their characteristics: location; orientation and interplanar spacing. These methods, which we refer to as plane orientation extraction (POE) and local crystallography mapping (LCM) make use of real-space data and allow for systematic analyses. We present here application of POE and LCM to datasets of pure Al, industrial aluminium alloys and doped-silicon. Data was collected both in DC voltage mode and laser-assisted mode (in the latter of which extracting crystallographic information is known to be more difficult due to distortions). The nature of the atomic planes in both datasets was extracted and analysed.

Research paper thumbnail of Increasing the strength of nanocrystalline steels by annealing: Is segregation necessary?

Scripta materialia, Jan 15, 2015

Hardening phenomena in nanocrystalline metals after annealing have been widely reported, and the ... more Hardening phenomena in nanocrystalline metals after annealing have been widely reported, and the subject of much recent debate. Solute segregation to grain boundaries and dislocation source hardening have been proposed to cause the strengthening. To shed light on the dominant mechanisms, we present results from mechanical experiments and atom probe tomography on samples with similar grain size but different amounts of solute segregation and different boundary chemistries.

Research paper thumbnail of Application of FIB-EBSD Tomography for Understanding Annealing Phenomena in a Cold Rolled Particle-Containing Nickel Alloy

Materials Science Forum, 2007

Research paper thumbnail of Martensitic transformation in an intergranular corrosion area of austenitic stainless steel during thermal cycling

Research paper thumbnail of MECHANICAL BEHAVIOUR AND THE ROLE OF MICROSTRUCTURE IN CONTACT LOADING OF TiN COATINGS

Research paper thumbnail of STUDY OF RECRYSTALLIZATION IN COLD ROLLED IF STEEL and NICKEL USING 3-D FIB-EBSD TOMOGRAPHY

Research paper thumbnail of GENERATING 3-D MICROSTRUCTURES USING FIB-EBSD TOMOGRAPHY

Research paper thumbnail of Micro-sized Artificial Muscles for Bio-inspired Applications

Research paper thumbnail of Applications for atom probe crystallography

Research paper thumbnail of THE APPLICATIONS OF FOCUSED ION BEAM TECHNOLOGY TO NANOSCALE MATERIALS

Research paper thumbnail of Using Small Angle Scattering and Atom Probe Tomography as Complementary Tools for Characterising Precipitate Microstructures at the Nanoscale

Research paper thumbnail of Effect of ion irradiation on tensile ductility, strength and fictive temperature in metallic glass nanowires

Research paper thumbnail of Site-specific specimen preparation for atom probe tomography of grain boundaries

Physica B Condensed Matter

Atom probe tomography is a powerful technique that is highly suited to the study of low-level gra... more Atom probe tomography is a powerful technique that is highly suited to the study of low-level grain boundary segregation. However, difficulties in preparation of the required needle-shaped specimens containing the area of interest have precluded detailed studies of this nature to date. Two new methods are presented to manufacture atom probe tips from site-specific areas using a dual-beam focused ion beam (FIB)/scanning electron microscope (SEM). One involves the use of electropolished blanks, which are resharpened using the ion beam, and the second utilises micromanipulators to lift the area of interest directly from a bulk specimen before ion beam fabrication of the tip. The advantages and drawbacks of each technique are compared.

Research paper thumbnail of Atom probe specimen fabrication methods using a dual FIB/SEM

Ultramicroscopy

A dual FIB/SEM provides solutions to many challenges in atom probe specimen preparation. When com... more A dual FIB/SEM provides solutions to many challenges in atom probe specimen preparation. When combined with an in situ lift-out capability, the versatility of this tool allows almost any region of interest, in almost any geometry, to be placed at the apex of a specimen tip. Several preparation techniques have been developed in response to specific application requirements; for example, in cases where materials are not suitable for electropolishing, or where site-specific analysis is required. Two general techniques, with wide-ranging potential applications, are described in detail here. The first is a 'cut-out' technique that provides a relatively quick means of micro-tip specimen preparation from bulk material samples. The second method is a 'lift-out' technique that can be used in an in situ or ex situ mode and does not require the preparation of pre-sharpened mounting points.

Research paper thumbnail of Recent Advances in FIB-based Site-specific Atom Probe Specimen Preparation Techniques

Microscopy and Microanalysis

Research paper thumbnail of New atom probe approaches to studying segregation in nanocrystalline materials

Ultramicroscopy

Atom probe is a technique that is highly suited to the study of nanocrystalline materials. It can... more Atom probe is a technique that is highly suited to the study of nanocrystalline materials. It can provide accurate atomic-scale information about the composition of grain boundaries in three dimensions. In this paper we have analysed the microstructure of a nanocrystalline super-duplex stainless steel prepared by high pressure torsion (HPT). Not all of the grain boundaries in this alloy display obvious segregation, making visualisation of the microstructure challenging. In addition, the grain boundaries present in the atom probe data acquired from this alloy have complex shapes that are curved at the scale of the dataset and the interfacial excess varies considerably over the boundaries, making the accurate characterisation of the distribution of solute challenging using existing analysis techniques. In this paper we present two new data treatment methods that allow the visualisation of boundaries with little or no segregation, the delineation of boundaries for further analysis and ...

Research paper thumbnail of Mining information from atom probe data

Research paper thumbnail of The effect orientation of features in reconstructed atom probe data on the resolution and measured composition of T1 plates in an A2198 aluminium alloy

Ultramicroscopy, Jan 14, 2015

Artefacts in atom probe tomography can impact the compositional analysis of microstructure in ato... more Artefacts in atom probe tomography can impact the compositional analysis of microstructure in atom probe studies. To determine the integrity of information obtained, it is essential to understand how the positioning of features influences compositional analysis. By investigating the influence of feature orientation within atom probe data on measured composition in microstructural features within an AA2198 Al alloy, this study shows differences in the composition of T1 (Al2CuLi) plates that indicates imperfections in atom probe reconstructions. The data fits a model of an exponentially-modified Gaussian that scales with the difference in evaporation field between solutes and matrix. This information provides a guide for obtaining the most accurate information possible.

Research paper thumbnail of Cover Picture: Revealing the Distribution of the Atoms within Individual Bimetallic Catalyst Nanoparticles (Angew. Chem. Int. Ed. 42/2014)

Angewandte Chemie International Edition, 2014

ABSTRACT To be able to correlate the catalytic properties of nanoparticles with their structure, ... more ABSTRACT To be able to correlate the catalytic properties of nanoparticles with their structure, detailed knowledge about their make-up on the atomic level is required. Herein, we demonstrate how atom-probe tomography (APT) can be used to quantitatively determine the three-dimensional distribution of atoms within a Au@Ag nanoparticle with near-atomic resolution. We reveal that the elements are not evenly distributed across the surface and that this distribution is related to the surface morphology and residues from the particle synthesis.

Research paper thumbnail of Titelbild: Revealing the Distribution of the Atoms within Individual Bimetallic Catalyst Nanoparticles (Angew. Chem. 42/2014)

Angewandte Chemie, 2014

ABSTRACT To be able to correlate the catalytic properties of nanoparticles with their structure, ... more ABSTRACT To be able to correlate the catalytic properties of nanoparticles with their structure, detailed knowledge about their make-up on the atomic level is required. Herein, we demonstrate how atom-probe tomography (APT) can be used to quantitatively determine the three-dimensional distribution of atoms within a Au@Ag nanoparticle with near-atomic resolution. We reveal that the elements are not evenly distributed across the surface and that this distribution is related to the surface morphology and residues from the particle synthesis.

Research paper thumbnail of A new systematic framework for crystallographic analysis of atom probe data

Ultramicroscopy, Jan 18, 2015

In this article, after a brief introduction to the principles behind atom probe crystallography, ... more In this article, after a brief introduction to the principles behind atom probe crystallography, we introduce methods for unambiguously determining the presence of crystal planes within atom probe datasets, as well as their characteristics: location; orientation and interplanar spacing. These methods, which we refer to as plane orientation extraction (POE) and local crystallography mapping (LCM) make use of real-space data and allow for systematic analyses. We present here application of POE and LCM to datasets of pure Al, industrial aluminium alloys and doped-silicon. Data was collected both in DC voltage mode and laser-assisted mode (in the latter of which extracting crystallographic information is known to be more difficult due to distortions). The nature of the atomic planes in both datasets was extracted and analysed.

Research paper thumbnail of Increasing the strength of nanocrystalline steels by annealing: Is segregation necessary?

Scripta materialia, Jan 15, 2015

Hardening phenomena in nanocrystalline metals after annealing have been widely reported, and the ... more Hardening phenomena in nanocrystalline metals after annealing have been widely reported, and the subject of much recent debate. Solute segregation to grain boundaries and dislocation source hardening have been proposed to cause the strengthening. To shed light on the dominant mechanisms, we present results from mechanical experiments and atom probe tomography on samples with similar grain size but different amounts of solute segregation and different boundary chemistries.

Research paper thumbnail of Application of FIB-EBSD Tomography for Understanding Annealing Phenomena in a Cold Rolled Particle-Containing Nickel Alloy

Materials Science Forum, 2007

Research paper thumbnail of Martensitic transformation in an intergranular corrosion area of austenitic stainless steel during thermal cycling

Research paper thumbnail of MECHANICAL BEHAVIOUR AND THE ROLE OF MICROSTRUCTURE IN CONTACT LOADING OF TiN COATINGS

Research paper thumbnail of STUDY OF RECRYSTALLIZATION IN COLD ROLLED IF STEEL and NICKEL USING 3-D FIB-EBSD TOMOGRAPHY

Research paper thumbnail of GENERATING 3-D MICROSTRUCTURES USING FIB-EBSD TOMOGRAPHY

Research paper thumbnail of Micro-sized Artificial Muscles for Bio-inspired Applications

Research paper thumbnail of Applications for atom probe crystallography

Research paper thumbnail of THE APPLICATIONS OF FOCUSED ION BEAM TECHNOLOGY TO NANOSCALE MATERIALS

Research paper thumbnail of Using Small Angle Scattering and Atom Probe Tomography as Complementary Tools for Characterising Precipitate Microstructures at the Nanoscale