Search Results for atom probe tomography

As high-entropy alloys become more complex in terms of microstructure, phase stability, and intermetallics, the advent of sophisticated analytical instruments is helping scientists to develop new materials with the most desirable properties. The analysis techniques described in this article include electron energy loss spectroscopy, electron probe microanalysis, atom probe tomography, and x-ray absorption spectroscopy.

This article reviews the analytical techniques used for phase identification in components, including x-ray diffraction, metallography/microscopy, electron backscatter diffraction, trasmission electron microscopy,and atom probe tomography. The article addresses the advantages and disadvantages of each technique compared to the other approaches.

Researchers at Pacific Northwest National Laboratory (PNNL) use a combination of scanning and transmission electron microscopy, atom probe tomography, and focused ion beam milling to analyze corrosion and crack structures in light-water reactor components with near-atomic spatial resolution.

This article explains how SEM, TEM, and atom probe tomography are being used in the development of additively manufactured high-entropy alloys (HEAs), revealing critical features such as anisotropic microstructure and metallurgical defects. It also discusses ongoing efforts to improve the predictability and analysis of HEA microstructure using data-driven approaches.

Using advanced characterization techniques on surface hardened steels builds a richer understanding of the underlying metallurgical phenomena.

Development of new, radiation-tolerant materials that maintain the structural integrity and safety margins over the course of a nuclear power reactor’s service life requires the ability to predict degradation phenomena. Modern post-irradiation examination methods make use of specialized high-flux test reactors and dedicated characterization facilities to limit occupational exposure and prevent the spread of radioactive contamination. This article illustrates the use of these advanced techniques to characterize precipitates in neutron-irradiated Fe-Cr-Al alloys.

Optimizing the integrity and performance of highly engineered surfaces and structures requires the ability to visualize and understand material behavior over multiple length and time scales from a three-dimensional perspective. The Electron Microscopy Centre at the University of Manchester is equipped for such work as demonstrated in problem-solving scenarios involving multiscale imaging and analysis of the progression of intergranular corrosion in Al alloy 2024, the catalytic effect of silver nanoparticles in seawater, recrystallization in a volume element of a bronze alloy, and defect progression on graphene surfaces.

There is growing interest in steels microalloyed with titanium, niobium, and molybdenum for use in high-temperature carburizing applications. This article describes methods for control of grain coarsening and work to commercialize microalloyed coarsening-resistant steels.

Affordable bulk production of a newly developed nanostructured bainitic steel is possible without using severe deformation or complex heat treatments. This article discusses the characteristics and significance of nanostructured bainite in terms of the transformation mechanism.

A mixed-reality application called HoloMicroscope helps microscopists make decisions and analyze data efficiently while using transmission electron microscopes. In the context of materials research, using mixed reality augments a user’s interaction by allowing them to see a TEM column and its control panels, while also interacting with three-dimensional holograms that are projected into their field of view. Introduction of mixed reality into a data-intensive research workflow could help accelerate scientific discovery. This article provides background about technology and a case study in its use.

Neutron-based imaging and measurement techniques are an ideal complement to x-ray methods for characterizing additively manufactured materials and components. This article presents examples showing how neutron radiography and residual strain measurements reveal the internal structure and stress distributions in highly engineered turbine blades produced by additive processes. It also discusses the development of neutron characterization tools at ORNL and a recent effort in which they were used to evaluate stress-relief treatments for large-scale metal AM structures.

Given the demonstrated antimicrobial properties of copper, it is incumbent upon materials scientists to design potent antimicrobial copper-containing stainless steels as an economical option.

Wavelength-dependent or hyperspectral imaging is a novel nondestructive characterization technique in the field of neutron radiography and computed tomography. A dedicated facility named VENUS is currently being built at Oak Ridge National Laboratory to provide these characterization capabilities for academia, industry, and other national laboratories. This feature article describes the VENUS capabilities for materials science and engineering, provides a quick overview of the modes of access of the facility, and illustrates the nondestructive measurements and interpretation of results.

Terahertz time-domain spectroscopy is a powerful and nondestructive analytical characterization technique for investigating ceramics, glasses, and composites.

Structural features, spatial locations, and morphological measures not readily attainable with 2D methods are now accessible using 3D microstructure characterization techniques.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: ASM announces 2019 award recipients; ASM Historical Landmark designation for the Ferreria Mirandaola Ironworks, Legazpi, Guipúzcoa, Basque Country, Spain; contributor profile for George E. Totten; professional profile for Brenda L. Garcia-Diaz.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: ASM names 2015 award recipients; Park Metallurgical/Heatbath Corporation in Detroit is selected for a 2015 ASM Historical Landmark Award; ASM student board members for 2015-2016 announced; Stan Theobald, former ASM Managing Director, retires from ASM; author spotlight for George Krauss; volunteer profile for Steve Brubaker.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: Appointment of 2021-2022 ASM Committee and Council chairs; ASM's new Executive Director, Sandy Robert; contributor spotlight for Roch J. Shipley.