Search Results for scanning electron microscopy

In cold spray characterization, scanning electron microscopy is used to analyze feedstock powders for particle size, distribution, shape, and chemical composition prior to spraying. SEM is used extensively to characterize coating chemistry via energy-dispersive x-ray spectroscopy (EDS). Coating thickness and interface contour can be characterized in a manner that makes SEM an indispensable and versatile tool for evaluating coating integrity in the as-sprayed condition, as well as in developing an understanding of bonding to the substrate.

This study presents a comprehensive scale-bridging characterization approach to investigate acicular ferrite nucleation in electron beam welded S355 ML steel, demonstrating the critical role of titanium oxide particles in promoting fracture-resistant microstructures for offshore wind monopile applications. Using a multi-technique methodology spanning light microscopy, scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and transmission Kikuchi diffraction (TKD), the researchers identified and analyzed particles that serve as nucleation sites for acicular ferrite formation. This entry won the prestigious 2024 Jacquet-Lucas Award for Excellence in Metallography at the International Metallographic Contest held during IMAT in Cleveland, October 2024.

Scanning electron microscopy and energy dispersive x-ray spectroscopy open new windows into glassmaking processes.

3D laser microscopy is opening new areas of study for metallic alloys and coatings in power generation applications. This article describes some case studies where laser microscopy has augmented, and in some cases replaced, metallic alloy characterization using optical microscopy or scanning electron microscopy.

Many broken parts look similar at a glance, but examination of the failed part using advanced equipment and methods such as scanning electron microscopy (SEM) reveals much more about the origins of the failure. This article presents a case history involving SEM analysis of a trailer hitch fatigue failure.

This article describes traditional methods for identifying particle contamination in manufacturing processes as well as a new alternative method that uses scanning electron microscopy combined with energy-dispersive x-ray spectroscopy. The new system provides efficient, accurate microanalysis to identify the size, shape, and chemical composition of particles. A case study in automobile manufacturing is presented.

This new article series explores the indispensable role of characterization in the development of cold spray coatings and illustrates some of the common processes used during coatings development. This article provides a list of techniques to be covered in subsequent articles.

Focused ion beam (FIB) systems are selectively used in cold spray coating characterization to gather information on the nature of splat formation, single splats, multiple splats, or the coating-substrate interface. Electron probe microanalysis has been used in cold-sprayed coating characterization primarily to understand the bonding mechanism at the coating-substrate interface.

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.

Two case studies highlight the strengths and weaknesses between traditional metallurgical techniques and 3D micro-computed tomography, as well as the interplay between the two.

New electrical, mechanical, and chemical testing capabilities give scanning electron microscopes the feel of a self-contained “nano-laboratory.” Several developments in SEM technology allow new and more flexible approaches to the analysis of novel systems, such as Li battery-related materials, nanostructured and nanoporous materials, and novel approaches to 3D analysis.

Researchers at the University of Michigan are investigating the complex heterogeneous phase transformations associated with deformation in shape memory alloys by means of in-situ tensile loading in combination with SEM, EBSD, and digital image correlation. This article describes the general approach and presents and interprets test results.

The ability to produce bulk metallic nanolaminates has greatly expanded the potential structural applications for these materials, motivating investigations into formability, joining techniques, and deformation behavior. This article presents an overview of both the accumulative roll bonding process and the deformation behavior for copper-niobium nanolaminates. This entry won the Jacquet-Lucas Award for Best in Show at the 2014 International Metallographic Contest.

Automated mineralogical analysis using near-infrared spectroscopy and X-ray diffraction can improve ore control and process efficiency resulting in reduced processing costs and higher yields.

This entry won the prestigious Jacquet-Lucas Award for Best in Show in the 2020 International Metallographic Contest. In the research discussed in this article, light microscopy was applied to a Co28Cr6Mo alloy for a biomedical application processed by laser bed powder fusion (LPBF) additive manufacturing.

A pin used to hold the side plates together in a conveyor chain system fractured and failed, prompting a metallurgical failure analysis. This case study reviews the analytical steps and conclusions from the study of the failed pin.

In this study, 316L stainless steel samples were plasma nitrided for 64 h at 370-420 °C then subjected to surface hardness and pitting corrosion testing. The results show that interstitial hardening with nitrogen significantly improved the surface hardness as well as the pitting corrosion resistance of the austenitic stainless steel.

Characterizing ice and snow is important not only for building accurate climate models, but also for activities such as relating the mechanical properties of sea ice to its microstructure so that the interaction of ice with ships and structures can be better understood. This article describes the microstructural characterization of ice. Many microstructural characterization techniques that can be applied to other materials also can be used to examine ice.

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.

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