The 7th International Congress on 3D Materials Science (3DMS 2025): Poster Session
Program Organizers: Henry Proudhon, Mines Paris Centre Des Materiaux; Can Yildirim, European Synchrotron Radiation Facility
Tuesday 4:40 PM
June 17, 2025
Room: Platinum Ballroom 6
Location: Anaheim Marriott
Cancelled
3D Large Volume Non-Destructive Grain Structure Characterization in Metallic Alloys Using Lab-Based Diffraction Contrast Tomography (LabDCT): Kaushik Yanamandra1; Nathan Johnson1; Hrishikesh Bale1; Jette Oddershede2; Jun Sun2; 1Carl Zeiss Microscopy; 2Xnovo Technology
The grain boundary(GB) are essential information to analyze grain boundary related behaviors such as preferential precipitation or intergranular cracking in polycrystalline materials. Accessing the necessary parameters to describe a GB on the mesoscopic scale is beyond the reach of 2D characterization techniques and is only achievable through a 3D approach. With the capability to map the grain morphology and crystallographic orientation non-destructively in 3D, lab-based diffraction contrast tomography (DCT) using X-rays provides the necessary information to analyze the crystallographic parameters describing grain boundaries on the mesoscopic scale, including grain boundary misorientation angle/axis and plane inclination. In this work, we will present the results of using lab-based DCT to investigate the grain boundary characters in polycrystalline materials including ceramic examples, with further discussion of how the grain boundary properties are related to grain boundary behaviors such as grain boundary wetting and cracking.
4D Multimodal Testing and Numerical Simulations Applied to the Study of Incipient Crystal Plasticity: Clement Ribart1; Aldo Marano2; Wolfgang Ludwig3; Henry Proudhon1; 1Centre des Materiaux - Mines Paris; 2ONERA; 3ESRF
We present a multimodal analysis of incipient polycrystalline plasticity from a titanium tensile sample. The dataset was generated from experimental acquisitions involving synchrotron DCT and conventional EBSD at the initial and deformed state. The DCT allows to generate a 3D digital twin (1 cubic mm) on which a full field FFT simulation was performed with a finite strain continuum crystal plasticity formalism. Following a careful registration of the modalities, a detailed comparison was performed at the mesoscopic, intergranular and intragranular (1 cubic µm voxel resolution) scales. Results demonstrated the higher performance of DCT over EBSD to track orientations while revealing in bulk new sub-grains mechanisms from the computation of GND fields. In addition the numerical results show good agreement with experiment at every scale while offering extra information to interpret the link between disorientation fields and plastic slip activity.
A Novel Method for Microstructure Prediction of Austenitic Stainless Steel Based on Machine Learning: Yuqing Du1; Jun Sun2; Håkon W. Ånes2; Fei Chen1; 1Shanghai Jiao Tong University; 2Xnovo Technology ApS
The prediction of mixed grains is crucial for determining whether austenitic stainless steel achieves excellent mechanical properties after solution treatment. In this presentation, machine learning approach is adopted to predict the microstructure evolution of austenitic stainless steel during hot deformation and solution treatment. Five different machine learning models are compared, using experimental data from large-area EBSD measurements covering mixed grain areas. Shapley Additive exPlains (SHAP) method was found to be most accurate interpreting the model to find key factors affecting the formation of mixed grains in hot deformation and solid solution treatment. Moreover, a time series 3D grain data about these key factors was researched from lab-based diffraction contrast tomography (Lab-based DCT) characterizing the grain coarsening processing during solution treatment. Various aspects coupling 2D and 3D experimental data to machine learning will also be discussed.
Design and Construction of an Native Water Atomizer for Metal powder Feedstock
Production toward Sustainable Corrosion Protection Applications
: Ayodele Daniyan1; IreOluwa Salami1; Emmsnuel Lamikanra1; Olalekan Ayodele1; Charles- Mbohwa2; 1Obafemi Awolowo University; 2University of South Africa
In the modern engineering designs, powder feedstock has been recognized to successfully use as an anticorrosion coating in oil and gas pipelines against corrosion attack and water atomization has been discovered to be a unique route of manufacturing these protective metals’ powders. This work developed a water atomizer equipment for metal powder manufacturing. The machine was designed such that temperature gradient could be adjusted. Zinc metallic powder was successfully produced with the water atomizer. The capacity of the molten metal is about 4kg. The diameter of the exit nozzle’ diameter where the molten metal flows out from is 5mm. The water atomizer was designed to use a separate furnace for scraps’ meltingThe result obtained shows that the developed atomizer was able to produce the proposed metallic powders from zinc, with a particle size of 0.3 mm
Design Considerations for Printed Functional Prototypes: Mark Patterson1; Mathew Kuttolamado2; Carlos Mora Salcedo2; Herman Neid3; Chris Stricklan4; ANdy Bujanda5; Paul Allison6; Rachael Swinney6; Robert Amaro1; Paul Brune1; Madison Parks1; James Tucker1; Jason Benoit7; Victor Yun8; Grace Kim8; 1Kratos SRE; 2Texas A&M; 3Lehigh University; 4Kraetonics; 5US Army DEVCOM; 6Baylor University; 7Sciperio; 83D Flexible
Additive manufacturing allows the printing of multi-material systems containing metals, polymers, ceramics and functional electrical circuits allowing the printing of fully functional prototypes. Design considerations are required to combine both interfaces between dissimilar materials and the use loads and environments that can introduce complex and directional loads. The design of polymer-metal and metal-ceramic interfaces has been investigated with respect to the load dependent failure mechanisms. The failure of printed electrical circuits has also been characterized highlighting the need for design improvements and process improvements based on the failures identified.
Experimental and Modelling Study of Mechanical Failure in 400 nm Porous Glass Using In Situ Nanoscale 3D X-Ray Microscopy: Stephen Kelly1; Sebastian Schafer2; François Willot3; Hrishikesh Bale1; Mansoureh Norouzi Rad1; Dirk Enke4; Juliana Martins de Souza e Silva5; William Harris6; 1Carl Zeiss RMS; 2Martin-Luther-Universität Halle-Wittenberg; 3Mines ParisTech; 4Universität Leipzig; 5Fraunhofer Institute for Microstructure of Materials and Systems IMWS; 6Carl Zeiss Microscopy
Porous glasses find uses in optics, heterogeneous catalysis, sensors, chromatography, and as hosts for nanoparticles and biocompounds mainly due to their high specific surface area and high thermal and chemical resistances. For these uses, the mechanical stability of porous silica is a requirement to guarantee resilience, load-bearing capacity, and fatigue resistance. With pore and strut sizes in the nanometer to micrometer range and a bicontinuous 3D structure, understanding the relationship between structure, processing, and mechanical properties is challenging. In this study, we used nanometer resolution X-ray computed tomography (nano-CT) to image a controlled pore glass (CPG) with 400 nm-sized pores under in-situ uniaxial compression. Critically, by combining 3D imaging data with computational tools, we quantitatively analyze the microstructural changes within the CPG sample, mapping displacements and strain fields, and show agreement with FFT/Phase Field simulations in explaining the appearance of cracks and brittle failure.
Grain Structure Evolution During Heat Treatment of a Semisolid Al-Cu Alloy Studied With Lab-Based Diffraction Contrast Tomography: Jun Sun1; Jules Dake2; Jette Oddershede1; 1Xnovo Technology; 2Ulm University
3D experimental data of simultaneously high temporal and spatial resolution is key to validation of computational modelling of materials phenomena. In this study, we exploit lab-based X-ray imaging, combining absorption contrast tomography and diffraction contrast tomography, to capture the evolution of grain structure over a series of interrupted in-situ heat treatments of a semisolid Al-Cu alloy. Multiple aspects of the microstructure are characterised comprehensively on the meso-scopic scale, including grain coarsening driven by Ostwald ripening, grain rotation driven by grain boundary energy as well as grain boundary wetting. With the time resolved response of the selected Al-Cu model alloy system, the present work provides insights into the rearrangement, densification and coarsening of powder compacts at late-stage sintering, revealing the crucial impact of crystallography upon the microstructural evolution.
High-Fidelity 3D Microstructural Characterization of ZrB2 During Hot-Pressing: Randi Swanson1; Darko Kosanovic2; Michael Chapman3; Ashley Hilmas3; Lisa Rueschhoff3; Michael Uchic3; Wei Xiong4; Hessam Babaee4; William Fahrenholtz2; Scott McCormack1; 1University of California Davis; 2Missouri Science and Technology; 3Air Force Research Laboratory; 4University of Pittsburgh
Standard ultra-high temperature ceramic (UHTC) manufacturing results in components with large differences in properties due to variability in microstructural “critical flaw” distributions. Critical flaws can be any irregularity in a component, such as a secondary phase, cracks, pores, etc. This is problematic when designing reproducible UHTC components. The goal of this project is to understand how these critical flaws evolve during hot pressing of ZrB2 (a UHTC) by examining them in 3D. This study incorporates 3D imaging such as: (i) ex-situ X-ray µ-CT and (ii) 3D electron imaging and backscattered diffraction data collected at different stages of densification. 3D microstructure statistics along with unique observations of individual pore and secondary phase evolution will be presented. This data is brought together to give a holistic view of the densification of ZrB2 during hot pressing at multiple length scales.
High Accurate Modelling and Large-Scale Simulation of Melt Pool Dynamics in Metal Additive Manufacturing Using Phase-Field Lattice Boltzmann Method: Konosuke Ikeda1; Shinji Sakane1; Takayuki Aoki2; Tomohiro Takaki1; 1Kyoto Institute of Technology; 2Institute of Science Tokyo
Material structures in metal additive manufacturing are formed through melting and solidification in laser scanning. The melt pool flow plays important role for the formation of the solidification structures. In this study, a phase-field lattice Boltzmann (PF-LB) model was developed to numerically reproduce the melt pool flow with high accuracy. In addition, since high-resolution is required for the high-accurate melt pool flow simulation, we implemented multiple GPU parallel computing to achieve large-scale simulations. Then, we validated the developed simulation method by comparing the results with experimental results, such as melt pool and keyhole shapes.
In-Situ Characterization of Martensitic Phase Transformation Interfaces in CuAlNi During Mechanical Cycling Using Dark-Field X-Ray Microscopy: Edith Celeste Perez-Valenzuela1; Adam Creuziger2; Sangwon Lee1; Evan Rust2; Raquel Rodriguez Lamas3; Albert Zelenika3; Can Yildirim3; Carsten Detlefs3; Ashley Bucsek1; 1University of Michigan; 2National Institute of Standards and Technology; 3European Synchrotron Radiation Facility
A reversible martensitic phase transformation is the deformation mechanism behind the functional properties of many multiferroic materials including shape memory alloys. During forward and reverse transformation, interfacial stress fields emerge at phase interfaces, leading to a hysteresis and the formation of undesirable dislocations. Here, we use in-situ dark-field X-ray microscopy (DFXM) to characterize the nucleation and growth of these phase interfaces during mechanical cycling of a CuAlNi shape memory alloy. The results show the 3D emergence and evolution of individual phase interfaces and spatially-mapped orientation and elastic strain, including the interfacial elastic strain fields at the phase interfaces. These findings will contribute to an improved fundamental understanding of the origins of hysteresis and functional fatigue in functional materials that undergo reversible martensitic phase transformations.
In-Situ Characterization of Supercritical Martensitic Phase Transformations in NiFeGaCo Single Crystals Using High-Energy Diffraction Microscopy: Timothy Thompson1; Abdulhamit Sarac1; Sangwon Lee1; Amlan Das2; Fei Xiao3; Ashley Bucsek1; 1University of Michigan; 2The Cornell High Energy Synchrotron Source (CHESS)
; 3Shanghai Jiao Tong University
Superelastic behavior, enabled by reversible martensitic phase transformations, has been observed in many multiferroic materials like shape memory alloys. Typically, martensitic phase transformations involve the formation and migration of interfacial stress fields at phase interfaces, causing hysteresis and degradation of superelastic behavior. However, recent research indicates that above a critical temperature (in a supercritical thermodynamic state), the transformation occurs with exceptional cyclic stability and no hysteresis. This study uses high-energy diffraction microscopy (HEDM) to characterize martensitic phase transformations below ("subcritical") and above ("supercritical") the critical temperature during compression of NiFeGaCo ferromagnetic shape memory alloys. In-situ HEDM experiments are supported by in-situ differential interference contrast (DIC) optical microscopy. Results reveal the evolution of martensite within single crystals and changes in phase interfaces. These findings will enhance the fundamental understanding of supercritical martensitic phase transformations.
In Situ Measurement of Three-Dimensional Intergranular Stress Localizations and Grain Yielding Under Elastoplastic Axial-torsional Loading: Yaozhong Zhang1; 1University of Michigan
The three-dimensional grain-scale elastoplastic response of solid bar samples during non-proportional (NP) axial-torsional loading was investigated using in situ high energy diffraction microscopy (HEDM) and companion crystal plasticity finite element (CPFE) modeling. Important stress metrics were tracked for ~ 300 grains under two different loading conditions: (i) Torsion-dominated loading (low NP) and (ii) Tension-torsion loading (high NP) in equiatomic NiCoCr, a representative multicomponent face-centered cubic (FCC) alloy. NP boundary conditions led to a complex interplay between stress components resulting in grain yielding near the sample surface largely driven by shear stress, whereas internal grain yielding largely accommodated by axial stress. Overall, grain-resolved stress localization trends were well-captured by the CPFE model, although some discrepancies in magnitude occurred due to initial type II residual stress distributions which were overcome via the superposition of initial residual stress states onto CPFE grain-resolved data.
Cancelled
In Situ Synchrotron-Tomographic and -Diffraction Investigation of the Effect of Tensile Load on Mg2Y1Zn(Gd, Ag, Ca): Domonkos Tolnai1; Dietmar Christian Florian Wieland1; Gabor Szakacs1; Daria Drozdenko2; Liam Perera3; Sharif Ahmed3; Kristian Mathis4; 1Institute of Metallic Biomaterials, Helmholtz-Zentrum Hereon; 2 Charles University; 3Diamond Light Source Ltd.; 4Charles University
The addition of Y and Zn can substantially improve the mechanical properties of Mg. Further alloying elements modify the secondary phases formed by the former, enabling to tailor the properties. Samples of pure Mg1.8Y0.6Zn and modified with 1.6 wt.% Gd, 1 wt.% Ag or 0.4 wt.% of Ca, were subjected to in situ tensile testing at the Dual Imaging And Diffraction beamline, Diamond UK, with a strain rate of 10-3 s-1, 10-4 s-1 and 10-5 s-1. During testing, tomographies were acquired to follow the crack initiation and evolution in 3D and diffraction patterns alongside the acoustic emission signal from the samples were also recorded to track the microstructural changes, thus enabling a comprehensive description of the damage in the samples leading up to the failure. The results show that the additional alloying elements and the strain rate both have a significant effect on the damage process and the failure.
Incorporating Experimental Data Into Molecular Dynamics: A Method for Voxel-Atomic Structure Conversion: Meizhong Lyu1; Zipeng Xu2; Gregory Rohrer2; Elizabeth Holm1; 1University of Michigan; 2Carnegie Mellon University
Many studies on three-dimensional grain growth depend on computer simulations due to the inherent challenges of experimental methods, such as limitations in characterization resolution and impurities. Computer simulations can model grain boundary motion in pure materials and capture detailed microstructural features. Unlike other mesoscale methods, molecular dynamics (MD) simulations do not rely on assumptions about grain boundary migration mechanisms. The existing methods of constructing computational microstructures from experimental data typically involve defining a surface mesh. However, the construction of a surface mesh from data points introduces a certain level of error, which may have an impact on the precision of the constructed atomic-scale microstructure. In this study, we developed a method to convert voxel-based structures from experimental data into atom-based structures for initial configurations in MD simulations. When comparing the MD simulation results with experimental data, we observed typical features of grain growth in nickel polycrystals.
Influence of Porosity on the Thermal Behaviour of 3D Porous Nanocomposite Constructs: Meenal Agrawal1; Rajiv Srivastava1; 1Indian Institute of Technology,New Delhi
While the porous materials are studied for various applications, their thermal behaviour is scantly reported. Addressing this, constructs with varying porosity were fabricated using Pickering emulsion templating. Stable emulsions of ε-caprolactone (CL) were prepared using silica nanoparticles as stabilizers and silicone oil as dispersed phase, which were further in-situ polymerized to form 3D nanocomposite constructs. The extent of porosity was controlled by dispersed phase volume of emulsions and crystallization behaviour was investigated under non-isothermal conditions. It was observed that inclusion of porosity led to extremely diminished crystallization temperature and kinetics. Various crystallization models were utilized to explain their crystallization behaviour. While a 3-regime crystallization was demonstrated by nonporous construct, presence of porosity led to 2-regime crystallization behaviour. This change in crystallization kinetics of the material was further prominent in materials with higher extent of porosity (>70%). Additionally, significant changes in crystalline structure due to porosity observed in x-ray diffractometer.
Investigating the Influence of Strain Rate on Hydrogen Embrittlement in Steel Sub-size Tensile Specimens Using 3D X-Ray Tomography: Luciano Santana1; Victor Okumko2; Andrew King2; Thilo Morgeneyer1; Jacques Besson1; Yazid Madi1; 1Mines Paris PSL - Centre des Matériaux; 2Synchrotron SOLEIL
This study investigates the effect of strain rate on hydrogen embrittlement in ferritic-pearlitic E355 steel using sub-size tensile specimens and micrometer-scale 3D X-ray tomography. Tests were conducted in air and 100 bar hydrogen at varying strain rates, with some interrupted before rupture to capture damage evolution. Hydrogen reduces ductility, with losses reaching up to 62.8% at lower strain rates.3D X-ray tomography enabled the quantification of damage and the determination of its shape and orientation at different strain rates. At 5 × 10⁻⁴ s⁻¹, brittle surface cracks appear as flat ellipsoids perpendicular to the tensile axis, while ductile bulk damage consists of prolate voids aligned along it. Hydrogen-enhanced shearing promotes coalescence through slant fracture. At 1 × 10⁻⁵ s⁻¹, deeper hydrogen diffusion increases embrittlement, causing both surface and bulk damage to adopt a brittle, flat ellipsoidal morphology perpendicular to the tensile axis.
Large-Scale 3D Multi-Phase-Field Sintering Simulation of Texture Development by Templated Grain Growth: Aoi Nakazawa1; Shinji Sakane1; Tomohiro Takaki1; 1Kyoto Institute of Technology
It is well known that the properties of ceramics can be improved by tailoring the texture. For example, lamellar textured ceramics have high thermal conductivity along the lamella and good mechanical properties in the perpendicular direction. Templated grain growth (TGG) is a powerful texturing method. However, as microstructure evolution is strongly affected by various factors, such as matrix particle size, template particle size, and aspect ratio, it is difficult to experimentally determine these parameters to obtain an optimal microstructure. Multi-phase-field sintering (MPFS) simulator [Nakazawa et al. 2025], which can continuously reproduce from powder compaction to sintering for arbitrarily shaped particles, is a powerful tool to investigate effect of those parameters on TGG. Using the MPFS, we performed large-scale 3D TGG simulations by changing size and shape of matrix and template particles systematically, and investigated what is the dominant effect on the formation of texture microstructure.
Multiscale Qualitative and Quantitative Assessment of Microstructural Elements in the IN718 Nickel-Base Superalloy After Various Annealing Durations at 760°C: Adam Kruk1; Grzegorz Cempura1; 1AGH University of Krakow
Structural materials used in critical components in the energy and aerospace sectors operate under challenging environmental conditions, leading to gas corrosion and microstructural degradation due to high temperatures and complex stress states. Assessing the degree of microstructural degradation requires multiscale parameterization. 2D imaging using scanning and transmission electron microscopy enables phase composition identification based on TEM-SAED analysis, STEM-EDX, and high-resolution HRSTEM-HAADF imaging. To obtain information about the spatial distribution of specific microstructural elements, including their morphology, high-resolution 3D imaging techniques are required. One such technique is FIB-SEM tomography, which allows 3D reconstruction of microstructural elements with voxel resolution on the order of a few nanometers. These imaging methods and techniques enabled the analysis of microstructural changes caused by prolonged annealing at temperatures above the operating range of the IN718 alloy. Qualitative and quantitative changes in the microstructure were compared with data obtained through numerical simulations performed using Thermo-Calc 2024b software.
Observation of Damage and Fracture in Al-5Mg-2Si Cast Alloy by Means of Synchrotron Radiation Multi-Scale Tomography: Masakazu Kobayashi1; Shogo Furuta1; Pei Loon Khoo1; Yojiro Oba1; Hiromi Miura1; 1Toyohashi University of Technology
Hypoeutectic Al-Mg-Si cast alloy has a good balance of strength and ductility. However, coarse block-shaped Mg2Si surrounded by plate-shaped ones are formed depending on cooling rate and chemical composition. This characteristic shape of the particle might control ductility. In-situ observation of damage and fracture process during tensile deformation was conducted by means of synchrotron radiation multi-scale tomography to understand the role of coarse block-shaped Mg2Si particle on fracture in Al-5Mg-2Si casting alloy. It revealed that a block-shaped part that is in the center is definitely fractured when a plate in horizontal spread cracks, because plate-shape parts spread radially surrounding a block-shaped part. It is concluded that block-shaped parts were not the origin of cracking, though they can be frequently observed on fracture surfaces.
Quantitative Elemental Mapping of Bimetallic Nanoparticles From Atomic Scale STEM-HAADF Images: Adrien Moncomble1; Damien Alloyeau1; Maxime Moreaud2; Guillaume Wang1; Nathaly Ortiz-Peña1; Hakim Amara3; Riccardo Gatti3; Romain Moreau3; Christian Ricolleau1; Jaysen Nelayah1; 1Université Paris Cité, Laboratoire Matériaux et Phénomènes Quantiques, CNRS, F-75013; 2IFP Energies Nouvelles, 69360; 3Université Paris-Saclay, ONERA-CNRS, Laboratoire d’Etude des Microstructures, 92020
We propose a deep-learning method for quantifying atomic column composition in bimetallic nanoparticles (NPs) using high-angle annular dark field scanning TEM (HAADF-STEM). When traditional EDX techniques require high-brightness electron sources and are limited by noise at atomic resolution, HAADF-STEM images are promising alternative to get access to the chemical composition of NPs. In this approach, elemental composition is retrieved from HAADF signal intensities using a U-Net like deep-learning model trained on multislice-simulated images and corresponding elemental maps. Multislice simulations reveal that HAADF-STEM intensity is influenced by atomic column composition, configuration, and thickness, requiring a sophisticated model to capture these interactions. Our approach disentangles these parameters, allowing accurate predictions at atomic resolution and providing robust, high-throughput in situ quantification of elemental composition. This method offers a significant advantage over EDX by achieving non-destructive, contamination-free composition analysis, making it highly suitable for real-time experimental conditions.
Study of Three-Dimensional Granular Matter Using Tomography and Far-Field High-Energy Diffraction Microscopy: Will Hobson-Rhoades1; Yuefeng Jin1; Iñigo De Gracia1; Wenxi Li1; Janice Moya1; Amlan Das2; Katherine Shanks2; Ashley Bucsek1; Hongyi Xiao1; 1University of Michigan; 2Cornell High Energy Synchrotron Source
The general goal of this work is to understand force distributions within three-dimensional (3D) disordered contact networks of frictional granular materials. The advancement of 3D in-situ experimental techniques has made it possible to characterize the packing configurations and forces in 3D frictional stiff granular media. This study leverages X-ray tomography and far-field high-energy diffraction microscopy (ff-HEDM) to investigate different granular material topics: (1) the effect of different confinement geometries on the force and contact networks of monocrystalline ruby spheres under uniaxial compression; (2) the validation of Janssen's law in a uniaxial compression test on monocrystalline ruby spheres; (3) the packing geometry of silicon cubes, rods, and plates under uniaxial compression. Discrete element method (DEM) simulations are conducted to supplement the experimental results. The findings from this work will enhance the understanding of force distribution and contact networks in 3D granular materials and help improve the modeling of 3D granular systems.
The Dynamics of Grain Growth in Thin Specimens: The Role of Free Surfaces: Varun Srinivas Venkatesh1; Marcel Chlupsa1; Hrishikesh Bale2; Ashwin Shahani1; 1University of Michigan; 2Zeiss Research Microscopy Solutions
Optimizing the properties of polycrystalline materials requires significant microstructural design, driven by our understanding of grain growth. Studies on grain growth have focused mostly on system-wide properties like grain size and growth rate, often overlooking local geometric, topological, crystallographic, and network effects, factors that require reliable 3D measurement. Developments in laboratory-based X-ray diffraction contrast tomography (DCT) have enabled us to study the temporal evolution of an unprecedented 10,000 grains in a thin aluminum disc upon annealing, where the sample thickness is ~5x the initial grain diameter. With this data, we test the validity of the Lewis, von Neumann-Mullins, and the Aboav-Weaire laws for the ensemble of interior and surface-touching grains. Our analysis of surface and bulk grain boundary planes over time explores how curvature, crystallography, and free surface effects influence and constrain grain and grain boundary evolution. These insights deepen our understanding of microstructure evolution in thin samples.
Time-Resolved Measurement Capabilities at the Forming and Shaping Technology Beamline: Katherine Shanks1; Amlan Das1; Sven Gustafson2; 1Cornell University; 2Cornell High Energy Synchrotron Source
The Forming and Shaping Technology (FAST) beamline at the Cornell High Energy Synchrotron Source (CHESS) provides high-flux, high-energy (20-88 keV) x-rays and experimental infrastructure for the structural materials community. In particular, the beamline focuses on in-situ measurements probing material microstructure during thermomechanical loading and processing. The energy range covered by FAST allows for characterization of materials over a wide range of density and atomic weight, from lightweight composites to steels and nickel-based alloys, while the use of transmission geometry techniques (e.g. powder diffraction, absorption- and phase-contrast radiography) gives insight into the material state through the bulk of millimeter-scale specimens. Here, we describe recent developments focused on deployment of instrumentation tailored to time-resolved experiments, including high-frame rate area detectors and emerging techniques for real-time data monitoring to guide data collection strategy.
Unsupervised Learning for Structure Detection in Plastically Deformed Crystals: Armand Barbot1; Riccardo Gatti2; 1ONERA; 2CNRS
Molecular Dynamics is a powerful method allowing to simulate different materials at the particle scale such as glassy materials or metallic nanocrystals. To determine the local structure at the particle-scale, several approaches were developed, mainly relying on local order parameters to describe the surrounding environment of each particle. However, they are mostly relying on hand chosen criteria and thus only works for already known structures. In this study, we present an unsupervised learning method to automatically study and detect the different substructures appearing at the atomistic scale within a crystal under plastic deformation. This approach combines autoencoder, clustering and classification methods.By applying our method on a Nickel FCC nanocrystal plastically deformed under uniaxial compression, we were able to detect more sub-structures associated with plasticity and with a higher degree of precision than traditional hand-made criteria. This study was published on Computational Materials Science.