Characterization of Materials through High Resolution Coherent Imaging: Coherent Imaging and Phase Contrast I
Sponsored by: TMS Structural Materials Division, TMS: Advanced Characterization, Testing, and Simulation Committee
Program Organizers: Ross Harder, Argonne National Lab; Xianghui Xiao, Argonne National Laboratory; Richard Sandberg, Los Alamos National Laboratory; Saryu Fensin, Los Alamos National Laboratory; Brian Abbey, LaTrobe University; Ana Diaz, Paul Scherrer Institut

Tuesday 8:30 AM
February 28, 2017
Room: 25B
Location: San Diego Convention Ctr

Session Chair: Xianghui Xiao, Argonne National Laboratory

8:30 AM  
Biomimetic CaCO3 Complex Morphologies Studied by Coherent X-ray Diffraction Imaging: Yuriy Chushkin1; Thomas Beuvier2; Federico Zontone1; Oxana Cherkas2; Alain Gibaud2; 1European Synchrotron Radiation Facility; 2UniversitÚ du Maine
     We present a study of the growth mechanism and self organization processes observed during the formation of biomimetic CaCO3 micro-particles from a liquid solution by using coherent X-ray diffraction imaging (CXDI).Calcium carbonate (CaCO3) can be found in rock minerals and is widely used in industry. Also it is the main constituent of shells of marine organisms. Marine organisms form complex morphologies using CaCO3 and organic macromolecules. Yet little is know how these macromolecules direct precipitation and recrystallization of CaCO3. By analyzing the 3D structures of around 20 samples we could shed light on the pathway leading to the formation of complex morphologies down to the nanometer length scale. In particular, we discuss the role of macromolecules and concentration in the formation of micro-spheres and crystal growth and the connection between micro-particle shape and self-organization of the nano-crystals.

9:00 AM  
Biological and Bio-inspired Multifunctional Structural Materials: Ling Li1; 1Harvard University
    Biological systems have evolved many material designs for various mechanical purposes with additional properties such as lightweight, transparency, photoreception, and flexibility. In this talk, I will discuss my research on biological and bio-inspired multifunctional structural materials. In particular, the advantages of utilizing high-resolution synchrotron x-ray tomography techniques for this study are highlighted. First, we investigate the structural basis for the highly transparent yet damage tolerant bioceramic material from the windowpane oyster Placuna placenta. Combining quantitative indentation and synchrotron tomographic measurement, I show that the shell’s 3D integrated laminate structure leads to its remarkable damage resistance. Secondly, we explore the dual-functional design of the biomineralized armor of the chiton Acanthopleura granulata, which incorporates an integrated sensory system based on hundreds of mineral lenses. We demonstrated that these microscopic, mineralized lenses are able to form images, correlating well with ray-trace simulations by incorporating the quantitative structural information obtained from tomography data.

9:30 AM  
Biological Imaging Using Combined Ptychography and X-ray Fluorescence: Karolina Stachnik1; Martin Warmer1; Pawel Wrobel2; Felix Marschall3; Istvan Mohacsi3; Pontus Fischer1; Ismo Vartiainen4; Christian David3; Marek Lankosz2; Alke Meents1; 1Deutsches Elektronen-Synchrotron DESY; 2AGH University of Science and Technology; 3Paul Scherrer Institut; 4University of Eastern Finland
    Pathogenesis of many diseases is initiated by a number of cellular processes which are unquestionably affected by minor and trace elements, mainly metals. Studies of their contribution require knowledge of their spatial distributions within structures of biological tissue in relation to its (sub-)cellular morphology. Consolidation of ptychographic CDI and nanoscale X-ray fluorescence yields simultaneously complementary information on morphology and elemental distribution of investigated specimen. It therefore facilitates correlative study of radiation-sensitive biomedical samples. We present the application of simultaneous ptychography and nano-XRF of biological tissue sections and cells using fly-scan acquisition mode at beamline P11 at the PETRA III, DESY, Germany. With photon energies up to 8.5 keV, we could access XRF signal from majority of first-row transition metals, obtaining ptychographic reconstructions and corresponding XRF maps. Resolution of obtained images will be discussed and challenges in high-throughput imaging of weakly phase-shifting biomedical samples will be addressed.

9:50 AM  
Speckle-based X-ray Imaging at Diamond Light Source: Hongchang Wang1; Yogesh Kashyap1; Kawal Sawhney1; 1Diamond Light Source
    X-ray phase and dark-field imaging techniques provide important supplementary and inaccessible information compared to X-ray absorption imaging. Recently, X-ray speckle-based technique has shown great potential for retrieving X-ray absorption, phase and dark-field images simultaneously by using a simple experimental arrangement1, 2. Importantly, the technique has also been extended from a synchrotron light source to a lab-based microfocus X-ray source3. X-ray phase and dark-field tomography can reveal subtle details and distinctive features of the internal structure of a sample4. Details of the technique and representative examples of applications in both biomedical applications and material science will be presented. 1.H. Wang, Y. Kashyap, et al, Phys. Rev. Lett. 114, 103901 (2015). 2.H. Wang, S. Berujon, et al, Scientific Reports 5, 8762 (2015). 3.H. Wang, Y. Kashyap, et al, Scientific Reports 6, 20476 (2016). 4.H. Wang, Y. Kashyap, et al, Appl. Phys. Lett. 108, 154105 (2016).

10:20 AM Break

10:40 AM  
Real-time Direct and Diffraction Hard X-ray Imaging of Ultra-fast Processes: Alexander Rack1; Margie Olbinado1; Mario Scheel2; J÷rg Grenzer3; Andreas Danilewsky4; 1ESRF; 2Synchrotron Soleil; 3Helmholtz-Zentrum Rossendorf; 4Albert-Ludwigs-University Freiburg
    The potential of hard X-ray imaging to tackle scientific questions can be substantially increased when the dimension time is accessible. Ultra high-speed X-ray imaging related to materials sciences is of special interest. Nowadays, unprecedented temporal resolution with hard X-ray imaging can be reached at synchrotron light sources thanks to indirect detection schemes combined with high-speed cameras. Storage rings like European Synchrotron Radiation Facility can be operated in so-called timing-modes with reduced bunch number but increased electron bunch charge density per singlet. The polychromatic photon flux density at insertion-device beamlines during timing-modes is sufficient to capture hard X-ray images exploiting the light from one singlet. Hence, X-ray imaging depicting processes on the picosecond scale is nowadays accessible. Additionally, direct transmission with diffraction imaging can be combined to track crack propagation in crystals. Future developments and their potential in the frame of the proposed upgrade of storage rings will be discussed.

11:20 AM  
Some Recent Advances in the Theory and Modeling of Phase Contrast Imaging: John Barber1; 1Los Alamos National Laboratory
    Phase contrast imaging (PCI) is a transmission-based technique, usually thought of as a near-field method for weak phase samples. In PCI the exit wave leaving the sample consists of pure phase variation. This constitutes a profound constraint on the form of the exit wave and the characteristics of the diffracted field on a distant detector. We will describe how to leverage this constraint via a number of novel, non-iterative methods for analyzing the diffracted field and recovering information about the sample. These include texture-analysis techniques for reconstructing the distribution of length scales of, e.g. voids and damage within the sample, as well as mathematical methods that extend PCI theory to include any experimental geometry, from the near-field to the far-field. Finally, we will describe techniques for even highly-diffracted images that allow recovery of the exit wave for even strong phase objects.

11:50 AM  
Nanoscale 4D Microstructural Evolution of Precipitates in Aluminum Alloys Using Transmission X-Ray Microscopy (TXM): C. Shashank Kaira1; S.S Singh1; C Kantzos1; A Kirubanandham1; V De Andrade2; F De Carlo2; Nikhilesh Chawla1; 1Arizona State University; 2Argonne National Lab
    The complex distribution of different precipitate morphologies 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 and to better predict the alloy’s deformation behavior.