Advanced Characterization Techniques for Quantifying and Modeling Deformation: Session VI
Sponsored by: TMS Extraction and Processing Division, TMS Structural Materials Division, TMS: Advanced Characterization, Testing, and Simulation Committee, TMS: Materials Characterization Committee
Program Organizers: Arul Kumar Mariyappan, Los Alamos National Laboratory; Irene Beyerlein, University of California, Santa Barbara; Wolfgang Pantleon, Technical University of Denmark; C. Tasan, Massachusetts Institute of Technology; Olivia Underwood Jackson, Sandia National Laboratories
Wednesday 2:00 PM
March 2, 2022
Room: 207A
Location: Anaheim Convention Center
Session Chair: Peter Hedstrom, KTH; Yuki Yamamoto, Oak Ridge National Laboratory
2:00 PM
Enhanced Predictive Modelling of Laser Weld Failure Using 3D Characterization of 304L: Andrew Polonsky1; Mary Arnhart1; Alyssa Skulborstad1; Helena Jin1; Kyle Karlson1; Jonathan Madison1; 1Sandia National Laboratories
The mechanical response of laser welds in complex load states can be highly variable, underlying the need for models that can accurately predict mechanical behavior to ensure component performance. Here we present a finite element modelling framework designed to capture this variability through the incorporation of 3D micro-computed tomography (μCT) characterization of partial penetration butt welds of 304L under a variety of weld conditions. Idealized models utilizing homogenization approaches for local material properties fail to accurately predict mechanical response trends, revealing the need to include more detailed weldment geometry obtained via μCT. The improved model demonstrates the sensitivity of mechanical response to weld geometry, as well as the role of porosity in controlling weld failure. The tradeoffs between computational complexity and predictive capability for modelling failure of highly ductile materials will also be discussed.
2:20 PM
Investigation of the Microstructure and Plastic Deformation of AM 316L Stainless Steels: Marissa Linne1; Jean-Baptiste Forien1; Nicolas Bertin1; Margaret Wu1; Sylvie Aubry1; Tatu Pinomaa2; Anssi Laukkanen2; Kirubel Teferra3; Nathan Barton1; Y. Morris Wang1; Thomas Voisin1; 1Lawrence Livermore National Laboratory; 2VTT Research Centre of Finland; 3US Naval Research Laboratory
We will present our recent investigations of the plasticity of additively manufactured 316L stainless steels (AM316L SS) at quasistatic strain rates. We will first introduce the multi-scale microstructural features that are present in the as-built and annealed AM 316L SS. The second part will present how we test, characterize, and simulate the plastic deformation of different AM316L materials, with and without post-process heat treatment. We use in- and ex-situ electron microscopy (SEM and TEM), in-situ synchrotron high energy X-ray diffraction (HEXRD), mechanical testing, crystal plasticity simulations, atom sensitive HEXRD simulations, and cellular automata. We found the AM316L to deform with both dislocation slip and twinning. We also found an unexpected dislocations configuration in the sub-grain cell walls with a significant density of stacking faults representing a new strengthening source.This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
2:40 PM Invited
NOW ON-DEMAND ONLY – Modeling Precipitation in Alloy 347H for the XMAT Project: Michael Glazoff1; Jianguo Yu1; Michael Gao2; Yukinori Yamamoto3; Q.Q. Ren3; Jonathan Poplawsky3; Michael Brady3; Laurent Capolungo4; 1Idaho National Laboratory; 2NETL; 3ORNL; 4LANL
We present efforts to develop quantitative models of precipitation in alloy 347H using PRISMA. Precipitation models provide data for the development of chemistry- and precipitation-informed creep theory (LANL) and may facilitate developing alloys for extreme environments (ORNL). Results for the XMAT-generated precipitation data (750°C) and literature sources at 600-800°C, are presented. Research sponsored by the U.S. Department of Energy, Office of Fossil Energy, the Crosscutting Technology High Performance Materials Research Program.
3:10 PM Invited
Characterization of Microstructure Evolution and Micromechanics Behavior of Steels with Metastable Austenite during Uniaxial Tensile Loading: Jan Peter Hedstrom1; Benjamin Neding1; 1KTH
Metastable austenite is a key microstructural constituent in advanced steels, and its deformation behavior is strongly related with the stacking fault energy. The stacking fault energy in turn depends on chemical composition and temperature. To better understand deformation behavior of both single-phase austenitic steels and multi-phase steels we have therefore investigated the relation between stacking fault energy, for different alloys and temperatures, and; the microstructure evolution and micromechanics behavior during tensile testing. The main experimental methodology applied is in-situ high-energy x-ray diffraction and this is supplemented with electron microscopy and modelling. We show that the deformation behavior of the austenite in the steels investigated can be rationalized through proper predictions of the stacking fault energy during deformation.
3:40 PM Break
3:55 PM
Study of Microstructure Evolution due to Solid-state Thermal Cycling during AM via Laser-integrated Scanning Electron Microscopy: Juan Guillermo Santos Macias1; Alexandre Tanguy1; Manas Upadhyay1; 1Ecole Polytechnique
A significant portion of worldwide research efforts dedicated to Additive Manufacturing (AM) of metals is focused on studying melt pool dynamics and solidification. However, it is also important to study the Solid State Thermal Cycling (SSTC) occurring after solidification because the microstructural features determining the material response such as texture, internal strains, etc. are affected by SSTC. Taking into account the difficulty of studying the AM process during manufacturing, a laser-integrated SEM system has been developed. The laser-SEM coupling allows performing SSTC under controlled conditions; thus, one can use in-situ EBSD/HR-DIC to follow microstructure changes that could be induced during AM. Preliminary results from in-situ SSTC EBSD and HR-DIC experiments carried out on DED 316L steel are presented.These first experiments show the potential of the setup, since it allows to study any laser-based method, and it could even be used in other research fields, such as welding.