Micron最新文献

{"title":"Optimizing sample preparation for In situ TEM heating studies of aluminum alloys","authors":"Longhui Chen ,&nbsp;Chunhui Liu ,&nbsp;Jianshi Yang ,&nbsp;Peipei Ma ,&nbsp;Jun He","doi":"10.1016/j.micron.2025.103891","DOIUrl":"10.1016/j.micron.2025.103891","url":null,"abstract":"<div><div>Aluminum-copper-lithium (Al-Cu-Li) alloy is a key structural material in the aerospace field. Its mechanical properties are closely related to the dynamic evolution of T₁ phase during the aging process. To accurately capture this dynamic process, the <em>in situ</em> transmission electron microscope (TEM) combined with the microelectromechanical system (MEMS) heating chip was used to observe the T₁ precipitation behavior in an Al-Cu-Li alloy in real time. All experimental samples were solution treated at 510 °C for 30 min and water quenched externally, and then heated to 180 °C on a MEMS heater chip at a heating rate of 1 °C/s. This study presents an improved sample preparation and transfer protocol to mitigate Ga infiltration. High-angle annular dark-field scanning TEM (HAADF-STEM) and energy-dispersive X-ray spectroscopy (EDS) were used to evaluate the effects of preparation methods, transfer techniques, and sample thickness (80–300 nm) on gallium (Ga) and platinum (Pt) contamination and precipitation behavior. The results show that Ga segregation, in the form of ∼10 nm intragranular particles and grain boundary enrichment, significantly distorts the intrinsic precipitation of T₁ phases. However, combining an external transfer method with low-energy ion milling at an accelerating voltage of 3 kV effectively suppresses Ga/Pt contamination. Furthermore, sample thickness critically influences precipitation kinetics in Al-Cu-Li alloys: sub-100 nm samples exhibit surface-driven abnormal coarsening of T₁ precipitates, while samples exceeding 250 nm suffer from reduced imaging resolution due to limited electron transparency. A thickness range of 150–200 nm optimally balances resolution fidelity with representative precipitation dynamics.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103891"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144695356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive evaluation method for the effect of multiple environmental disturbance sources on scanning electron microscopy imaging by calculating distance correlation coefficients","authors":"Junhyeok Hwang ,&nbsp;In-Yong Park ,&nbsp;Takashi Ogawa","doi":"10.1016/j.micron.2025.103876","DOIUrl":"10.1016/j.micron.2025.103876","url":null,"abstract":"<div><div>A scanning electron microscope (SEM), an essential tool for high-resolution imaging at the nanometer scale, frequently suffers from the harmful effects of various environmental disturbance sources, such as magnetic, acoustic, and mechanical vibrations. Because these disturbance sources appear as similar defects on SEM images, identifying the major source is not straightforward but remains crucial for implementing countermeasures. This study presents a comprehensive evaluation method for assessing and analyzing the impact of these environmental disturbance sources on imaging. The method uses multiple sensors around the SEM, measures 10 channel signals in real time, analyzes frequency, and estimates the impact of the disturbance. Together with Fourier transform using Welch’s method, the distance correlation coefficient (DCC) analysis demonstrates the capability of the method to identify the major disturbance sources and assess their influence on SEM images. In particular, the DCC method is effective in determining the major disturbance source even in complex conditions in which multiple disturbance sources have a common frequency component or mixed influence on SEM imaging. This comprehensive approach to evaluating the impact of environmental disturbance on SEM imaging offers significant insights into maximizing SEM performance by mitigating harmful effects from the environment, thereby contributing to the improvement of not only image quality but also measurement accuracy based on SEM.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103876"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144605782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterizing α-phase variants in titanium alloys via EBSD: Understanding colour indexing challenges.","authors":"S L Lu, T T Wang, T Song, A E Medvedev, S D Luo, D Qiu, M Brandt, M Qian","doi":"10.1016/j.micron.2025.103893","DOIUrl":"10.1016/j.micron.2025.103893","url":null,"abstract":"<p><p>Electron Backscatter Diffraction (EBSD) inverse pole figure (IPF) maps are indispensable techniques for visualizing grain orientations in titanium alloys. However, differentiating the twelve α-phase variants formed during the β → α phase transformation, following the Burgers orientation relationship, presents a challenge due to overlapping colours in IPF maps. This study systematically investigates how α-phase variants are coloured in IPF X, Y, and Z maps, using a Ti-6Al-2Sn-4Zr-2Mo alloy sample fabricated via laser-based directed energy deposition of metals. By analysing the orientations of prior-β grains and their α-phase variants with Burgers orientation relationship, we illustrate why multiple variants share similar colours in IPF maps. Additionally, the correlation between IPF map colour distributions and Schmid factors for basal, prismatic, and pyramidal slip systems is explored, providing insights into slip activation and deformation behaviour. This work clarifies how α-phase variants are represented in IPF maps and addressing common ambiguities in interpreting EBSD data, providing a framework for accurate microstructural characterization. These findings highlight the need for complementary techniques to resolve colour-based limitations of IPF maps and support the design of tailored microstructures for improved mechanical performances.</p>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"103893"},"PeriodicalIF":2.2,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144804429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance verification of the \"ghost\"-free tomographic reconstruction method QURT","authors":"Norio Baba ,&nbsp;Hiroyuki Ishikawa ,&nbsp;Miki Ito","doi":"10.1016/j.micron.2025.103889","DOIUrl":"10.1016/j.micron.2025.103889","url":null,"abstract":"<div><div>We recently proposed a novel tomographic reconstruction method called the quantisation unit reconstruction technique (QURT) that reconstructs a tomogram by arranging grey-level quantisation units in three-dimensional image space through unique discrete processing. QURT significantly reduces artificial image “ghost” generation caused by the “missing-wedge” and the number of projection images, which are common limitations of conventional methods. Unlike other recently developed advanced methods, such as compressed sensing, QURT does not require any parameter adjustments or modeling based on prior knowledge but requires only a series of projection images and tilt-angle data. It does not select the processing target because it exploits the inherent constraints of projection theory. In this study, the practical performance and resolution of QURT were quantitatively evaluated in both real and frequency domains using Fourier ring correlation and other metrics in simulations with fine test patterns. Even in the presence of the missing-wedge, QURT generated almost no ghost image outside the test pattern region, considerably suppressing the artifacts. This advanced property was experimentally validated by applying HAADF-STEM tomography to analyse a catalyst sample (Pd/CeO₂–ZrO₂–Al₂O₃), which was particularly sensitive to ghost image generation inside pores. QURT clearly revealed the pore structure without compromising the low-contrast Al regions and without generating ghost images, even at a tilt step angle of up to 4°. In EDXS tomography, QURT also reconstructed a 3D elemental map even from a small number of 22 tilt series signal maps with the missing-wedges.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103889"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144703448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accessible and thorough magnetic field mapping of TEMs using a commercial Hall-sensor and TEM automation for in situ magnetic experiments","authors":"Sivert Dagenborg,&nbsp;Kristian Tveitstøl,&nbsp;Iryna Zelenina,&nbsp;Gregory Nordahl ,&nbsp;Magnus Nord","doi":"10.1016/j.micron.2025.103877","DOIUrl":"10.1016/j.micron.2025.103877","url":null,"abstract":"<div><div>For imaging and quantitative <em>in situ</em> experiments of magnetic materials in the transmission electron microscope (TEM), knowing the external magnetic field over the sample position and the parameters affecting it is crucial. Calibrating this thoroughly also requires an efficient method for sampling a large set of parameters. This work presents accessible solutions to both these problems, using a commercial Hall-sensor soldered onto a custom printed circuit board then inserted into a TEM biasing holder. This is enhanced by TEM automation using open-source Python scripting, enabling thorough and effective experimental measurements. The magnetic field in the sample position was measured over a range of positions, tilts and lens excitations for three different TEMs: The JEOL JEM-2100F. JEOL JEM 2100,and JEOL JEM-ARM200F. In objective lens-off mode these have remnant fields of up to respectively 19.19<!--> <!-->mT, 15.24<!--> <!-->mT and 8.95<!--> <!-->mT, all oriented downwards in the column. The magnetic fields had a strong decay in x- and y-positions of up to 13.1%. The objective lens gave a highly linear response to lens excitation up to 27.5% of max excitation. For the 2100F and 2100, fully exciting the objective lens caused a significant change in remnant field of above 4<!--> <!-->mT which was counteracted with lens relaxation. The image aberration corrector lenses in the ARM200F caused changes of 0.2<!--> <!-->mT. This magnetic field mapping enables quantitative <em>in situ</em> experiments with magnetic fields up to 2<!--> <!-->T.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103877"},"PeriodicalIF":2.2,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144780031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of scanning electron microscopy and energy-dispersive x-ray spectroscopy in the study of bronze disease on ancient copper-based artifacts","authors":"Laura A. Battista ,&nbsp;Maryam Golozar ,&nbsp;Ehsan Nikbin ,&nbsp;Dian Yu ,&nbsp;Masha Stanko ,&nbsp;Laura Lipcsei ,&nbsp;Jane Howe ,&nbsp;Doug Perovic","doi":"10.1016/j.micron.2025.103890","DOIUrl":"10.1016/j.micron.2025.103890","url":null,"abstract":"<div><div>Bronze disease is a severe type of degradation in ancient copper-based artifacts and poses challenges to their preservation. This “disease” is an active cyclic corrosion process primarily caused by chlorine, oxygen and moisture. Products formed during this process, such as cuprous chloride (CuCl), continue to spread across the artifact’s surface until all available oxygen is consumed, resulting in irreversible destruction. Bronze disease is difficult to distinguish from other corrosion processes, leading to inaccurate assessments of the degradation mechanisms affecting the artifact. Combined scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS) is a viable method for analyzing bronze disease in ancient artifacts and for differentiating it from other forms of degradation. This study investigated suspected bronze disease on a Chinese cast bronze vessel dating from the 11th – 10th century BCE, part of the collection at the Royal Ontario Museum in Toronto, Canada. Corrosion product sampled from the vessel using two different methods, was chemically and topographically analyzed using SEM-EDS. The first method involved the removal of corrosion product using a scalpel, resulting in the collection of mixed particles. The second method, involving the creation of replicas, utilized an adhesive to directly remove the corrosion product, capturing the particles in their original locations. The sampled material contained copper and chlorine, consistent with the presence of bronze disease, though further work is required for confirmation. Although both techniques can investigate bronze disease, the replica technique offers a more promising approach, as it enables more precise, site-specific analysis of the corrosion product.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103890"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144662404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Liquid-cell annular dark-field scanning transmission electron microscopy imaging of single crystal samples on a low-index zone-axis incidence condition","authors":"Masaki Takeguchi ,&nbsp;Jonathan Lueke ,&nbsp;Matthew Reynolds ,&nbsp;Baibing Zhao ,&nbsp;Ayako Hashimoto","doi":"10.1016/j.micron.2025.103888","DOIUrl":"10.1016/j.micron.2025.103888","url":null,"abstract":"<div><div>In liquid cell (LC) annular dark-field scanning transmission electron microscopy (ADF-STEM), the spatial resolution is limited by the low ratio of signals from samples to background signals from the silicon nitride window membranes and liquid. We report the development of a double-tilt LC holder for atomic-resolution LC-ADF-STEM imaging of single-crystal samples under zone-axis incidence conditions. A SrTiO₃ &lt;001&gt; lamellar sample, approximately 100 nm thick, was prepared using the focused ion beam technique and transferred onto a silicon nitride window membrane of an LC chip via a glass probe pick-up method in air, which avoids Ga ion beam-induced damage to the window membrane. The sample adhered to the high-flatness window membrane and remained immobile, even when embedded in a water droplet. The sample and pure water were enclosed in an LC and observed under &lt;001&gt; zone-axis incidence conditions using aberration-corrected ADF-STEM. Electron channeling along the atomic columns enabled atomic-resolution LC-ADF-STEM imaging with high contrast, sufficiently overcoming background signals from window membranes and liquids. This high-contrast imaging technique could lower the probe current and is expected to mitigate electron-beam-induced radiolysis and minimize undesired sample damage, particularly under high-magnification imaging conditions.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103888"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144670813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mesostructural alteration in porosity of iron tailings sand under freeze-thaw cycle studied by X-ray microcomputed tomography","authors":"Hongyue Zhang,&nbsp;Jiaxu Jin,&nbsp;Pengfei Wu","doi":"10.1016/j.micron.2025.103871","DOIUrl":"10.1016/j.micron.2025.103871","url":null,"abstract":"<div><div>After experiencing periodic freeze-thaw cycles, the mesostructure of tailings sand in the tailings pond in seasonal frozen regions deteriorates, which directly threatens the safe and stable operation of the tailings pond. In order to reveal the alterations law of the mesostructure of iron tailings sand under the action of freeze-thaw cycles, the pore structure of iron tailings sand was characterized based on industrial X-ray microtomography technology. The response and variation trends of the pore structure of tailings sand to the moisture content and the number of freeze-thaw cycles were analyzed. A numerical model considering the irregular characteristics of particles was established to explore the dynamic process of the mechanical response among tailings sand particles under the action of freeze-thaw cycles. The results show that: the freeze-thaw effect leads to a decrease in the friction angle among tailings sand particles and an increase in the number of particles with an orientation angle of 45 °. The influence of moisture content on the throat diameter and pore coordination number is greater than that of the number of freeze-thaw cycles. There is a dynamic balance between the connection of small pores and the splitting and disintegration of large pores under different numbers of freeze-thaw cycles. During the freezing process of pore water in tailings sand, the particles in the specimen expand from the center to the periphery, and a force chain discontinuity area appears in the center of the model. Moreover, the area of the force chain discontinuity region is affected by the moisture content and the number of freeze-thaw cycles. A higher moisture content results in a larger pore expansion rate, fewer inter-particle contacts and a greater volume expansion. The research results of this paper can provide a reference for the safe and stable operation of tailings dams in seasonal frozen regions, and also support the establishment of the strength deterioration mechanism of tailings sand at the mesoscale under the action of freeze-thaw and the analysis of its influencing factors.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103871"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144587447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comparison between hollow cone illumination and wavelet transform methods for chromatin fiber orientation measurement","authors":"Misa Hayashida ,&nbsp;Rinyaporn Phengchat ,&nbsp;Marek Malac ,&nbsp;Keiko Shimada ,&nbsp;Shigeo Mori ,&nbsp;Yoshio Takahashi ,&nbsp;Ken Harada","doi":"10.1016/j.micron.2025.103859","DOIUrl":"10.1016/j.micron.2025.103859","url":null,"abstract":"<div><div>Nucleosomes are proven to be the fundamental unit of chromosome structure. The stacking and folding of the nucleosome fibers within a chromosome is not fully understood. One of the reasons for the incomplete understanding of chromosome internal structure is that a nucleosome, about 11 nm in diameter, can not be resolved within the large chromatids (∼ 700 nm diameter) of a chromosome. In a transmission electron microscope (TEM), the large difference in size between the small diameter nucleosomes and a chromosome results in an extremely low contrast arising from individual nucleosomes. Consequently, the nucleosome fiber can not be detected within an intact chromosome. In this study, we compared two different methods in TEM, namely the hollow cone illumination (HCI) TEM and wavelet transform (WT) analysis on bright-field TEM (BFTEM) images, to analyze internal structure of chromosomes at length scales ranging from 10 to 30 nm. Isolated chromosomes were expanded and the orientation of the chromatin fibers was measured by HCI TEM and by WT applied to BFTEM. We demonstrated that the results obtained by the two methods are in an agreement.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"196 ","pages":"Article 103859"},"PeriodicalIF":2.5,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electron irradiation-based cleaning of the scanning electron microscope and its samples","authors":"András E. Vladár","doi":"10.1016/j.micron.2025.103857","DOIUrl":"10.1016/j.micron.2025.103857","url":null,"abstract":"<div><div>The deposition of carbonaceous material under electron beam irradiation is an old and persistent problem in scanning electron microscopy. It impedes high-resolution imaging and measurements, especially at the nanometer scale. The emergence of contamination is a complex process of adsorption, dissociation, and desorption of carbonaceous molecules. Depending on the kind and amount of precursor molecules, vacuum, sample material, temperature, and the intensity and energy of the irradiating electrons, deposition can overwhelm removal or the other way. Fortunately, with the introduction and commercial availability of low-energy, plasma-based, and other cleaning devices, contamination can be reduced to non-detectable levels. Plasma devices, working in low vacuum, which is necessary to start and sustain plasma generation, can effectively remove contamination precursor hydrocarbon molecules to the extent that a clean sample can be imaged and continuously measured for hours without deposition of any perceptible amount of carbonaceous contamination. Here, we report on the results of a new and effective cleaning device that has recently become available, which is different from plasma cleaning devices. It is based on low-energy electron irradiation and works in high and ultra-high vacuum (UHV).</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"196 ","pages":"Article 103857"},"PeriodicalIF":2.5,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144098970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}