4th International Congress on 3D Materials Science (3DMS) 2018: Phase Transformations, Particle Coarsening, Grain Growth, and Recrystallization I
Program Organizers: Hugh Simons, Denmark Technical University; Henning Poulsen, Denmark Technical University; David Rowenhorst, Naval Research Laboratory; Peter Voorhees, Northwestern University; Satoshi Hata, Kyushu Univ; McLean Echlin, UC Santa Barbara

Monday 9:10 AM
June 11, 2018
Room: Store Scene
Location: Kulturværftet (Culture Yard) Conference Center

9:10 AM  Invited
Application of Characterization, Modelling, and Analytics towards Understanding Process-structure Linkages in Metallic 3D Printing: Michael Groeber1; 1Air Force Research Laboratory
    We will present methods for combining process monitoring, thermal modeling and microstructure characterization together to draw process-to-structure relationships in metal additive manufacturing. The talk discusses heterogeneities in the local processing conditions within additively manufactured components and how they affect the resulting material structure. Methods for registering and fusing disparate data sources are presented and some effort is made to discuss the utility of different data sources for specific microstructural features of interest. The talk will highlight the need for improved understanding of metallic additive manufacturing processes and show that combining experimental data with modelling and advanced data processing and analytics methods will accelerate that understanding.

9:40 AM  
Dark Field X-ray Microscopy Study of Heat Treatment of Fe-Si and Fe-Si-Sn Alloys: Can Yildirim1; Nikolas Mavrikakis2; Melanie Gauvin3; Phil Cook1; Mustafacan Kutsal1; Ashley Bucsek4; Henning Poulsen5; Wahib Saikaly3; Roger Hubert3; Carsten Detlefs1; 1European Synchrotron Radiation Facility; 2Aix-Marseille University, Institut Matériaux Microélectronique Nanosciences de Provence-IM2NP; 3Onderzoeks Centrum voor de Aanwending van Staal; 4Colorado School of Mines; 5Technical University of Denmark
    Properties of engineering materials can be improved by controlling various microstructural developments in heat treatment processes. Here, we study the effect of Sn in recovery and recrystallization of cold rolled Fe-3%Si binary and Fe-3%Si-0.1%Sn ternary alloys by means of 3D X-ray diffraction (3DXRD) and dark field X-ray microscopy (DFXM). DFXM is a non-destructive technique that allows 3D mapping of orientation and lattice strain with 100 nm spatial and 0.001° angular resolution within individual grains embedded in bulk samples. We investigate grains with the <111> direction parallel to the normal direction of cold rolling. Surprisingly, the recrystallized grains in both binary and ternary alloys show internal low angle boundary networks. We discuss the role of Sn during recovery and how it affects the subsequent recrystallization process. Our results also show that deformed grains feature sub-micron size deformation bands both in as-cold rolled and recovered states.

10:00 AM Break

10:30 AM  
Understanding the Relationship Between Microstructure Evolution and Macroscopic Behavior in NiTi Martensite Reorientation: Ashley Bucsek1; Darren Pagan2; Darren Dale2; J.-Y. Peter Ko2; Aaron Stebner1; 1Colorado School of Mines; 2Cornell High Energy Synchrotron Source
    Together with phase transformation, the diffusionless rearrangement of crystallographic twins enables the functional behaviors of the vast majority of ferroic and multiferroic materials. As a result, understanding twin mobility is critical to the success of a wide variety of society-improving technologies driven by ferroic and multiferroic materials. In the case of ferroelastic alloys, or shape memory alloys (SMAs), the mobile twins exist in the martensite phase and is thus referred to as martensite reorientation. As a study into twin reorientation, we performed stress-induced reorientation experiments on martensitic NiTi SMAs using near-field and far-field 3D X-ray diffraction (3DXRD) and digital image correlation (DIC). The results reveal the microstructure evolution behind two types of macroscopic localized deformation bands. These bands proceed through the sample in sequence, exist on a specific crystallographic plane, and both result in and are assisted by the elastic misorientation of the lattice.

10:50 AM  
Understanding Grain Growth in 3D: Microstructural Evolution of Nickel during Multiple Annealing Stages Using Three-dimensional X-ray Microscopy: Aditi Bhattacharya1; C.M. Hefferan2; S-F. Li3; J. Lind4; Y-F. Shen1; R.M. Suter1; G.S. Rohrer1; 1Carnegie Mellon University; 2R. J. Lee Group; 3Ditto Inc.; 4Lawence Livermore National Laboratory
     Near-field High Energy X-ray Diffraction Microscopy(nf-HEDM), a non-destructive, synchrotron based 3D characterization technique was used to track the microstructural evolution of high purity polycrystalline Nickel annealed at 800°C and measurements were taken at five different times separated by 30 minute intervals. The temporal changes in crystallographic orientation, grain size and misorientation in the microstructure were measured over the different anneal states. Our algorithm tracks each grain during annealing and matches them based on orientation and spatial location, thereby allowing detailed analysis of the grain boundary (GB) character distribution, the relative GB energies, and the GB curvature distribution at each step during the interrupted thermal annealing. Our results have been compared with established theories of grain growth and we discuss the topological nature of grain boundary network like the Aboav-Weaire law, but in 3D. The present work attempts to demonstrate a correspondence between a grain’s growth trajectory and its neighborhood.

11:10 AM  
Nanoscale 4D Microstructural Evolution of Precipitates in Aluminum Alloys using Transmission X-ray Microscopy (TXM): C. Shashank Kaira1; Tyler Stannard1; Vincent De Andrade2; Francesco De Carlo2; Nikhilesh Chawla1; 1Arizona State University; 2Advanced Photon Source
    The complex distribution of different precipitate morphology can play a significant role in controlling the mechanical response of precipitation-strengthened alloys. It is well known that conventional characterization techniques like transmission electron microscopy and atom probe tomography have significant shortcomings in terms of their destructive nature and inability to sample a statistically relevant region. In this study, 3D X-ray nanotomography using Transmission X-ray Microscopy (TXM) has been employed to quantify, in detail, the evolution of the microstructure in an Al-3.5Cu alloy. Owing to its high spatial resolution, non-destructive nature and quick acquisition time, high temperature in situ studies were conducted to better understand the aging phenomena and the transformation reactions involved, in 3D. This technique was coupled with techniques like EBSD and micropillar compression, that allowed us to establish accurate structure-property relationships to better predict the alloy’s deformation behavior.

11:30 AM  
Parameter Estimation for Multi-phase-field Simulation Using Ensemble Kalman Filter: Akinori Yamanaka1; Yuri Maeda1; Kengo Sasaki1; 1Tokyo University of Agriculture and Technology
    In order to simulate the microstructure evolutions quantitatively using the multi-phase-field (MPF) model, we need to identify material parameters used in the MPF simulations from experimental data. Recently, direct observation of microstructure evolution processes has been possible using new experimental techniques like X-ray tomography. If the material parameters used for the MPF simulations can be estimated from the data obtained by such experimental techniques, the accuracy of the MPF simulations will be significantly improved. In this study, we propose a data assimilation (DA) methodology for estimating material parameters used for the 3D MPF simulation using the ensemble Kalman Filter (EnKF). The EnKF-based DA methodology is applied to estimate the anisotropic grain boundary mobility used in the 3D MPF simulation of polycrystalline grain growth. In this presentation, we show that our DA methodology can estimate the cusp of grain boundary mobility from a time-evolving 3D polycrystalline grain distribution.

11:50 AM  
The Dynamics of Complex Two-phase Mixtures During Coarsening: From Dendritic to Bicontinuous Mixtures: Yue Sun1; William Andrews2; Katsuyo Thornton2; Peter Voorhees1; 1Northwestern University; 2University of Michigan
    A combined theoretical and experimental approach is used to examine the nature of the coarsening process in morphologically and topologically complex two-phase microstructures found following dendritic solidification and in nanoporous gold. We examine the coarsening dynamics in three dimensions as a function of time using X-ray tomography and simulation. Using the two-point spatial correlations of the solid-liquid interfacial curvature, we show why dendritic solid-liquid mixtures exhibit classical t1/3 kinetics for the average length scale, yet are not self-similar as theory predicts. Large-scale simulations of coarsening in bicontinuous mixtures under both surface or bulk diffusion have been performed to determine the interfacial shape distributions that can then be compared to the experimentally measured distributions to understand the nature of the coarsening process in these systems.