Materials for High Temperature Applications: Next Generation Superalloys and Beyond: Poster Session
Sponsored by: TMS Structural Materials Division, TMS: Refractory Metals Committee
Program Organizers: Govindarajan Muralidharan, Oak Ridge National Laboratory; Martin Heilmaier, KIT Karlsruhe; Benjamin Adam, Oregon State University; Mario Bochiechio, Pratt & Whitney; Katerina Christofidou, University of Sheffield; Eric Lass, University of Tennessee-Knoxville; Jeremy Rame, Naarea; Sallot Pierre, Safran; Akane Suzuki, GE Aerospace Research; Michael Titus, Purdue University
Wednesday 5:30 PM
March 17, 2021
Room: RM 8
Location: TMS2021 Virtual
Session Chair: Govindarajan Muralidharan, Oak Ridge National Laboratory; Benjamin Adam, Oregon State University
Creep Deformation Behavior of Ni - 33 Co Alloy: Divya Bandla1; Atul Chokshi1; 1Indian Institute of Science Bangalore
Since the identification of dominating deformation mechanism in multi-principle elemental alloys (MPEAs) is difficult, we considered a relatively simple way to evaluate the deformation mechanisms, to approaching the MPEAs through the concentrated solid solution alloys. Ni33Co alloy with a grain size of 100 µm was prepared through the melting, casting, rolling, and recrystallization. The XRD technique confirms the FCC crystal structure with the lattice parameter of 0.3546 nm. The elastic modulus of the alloy is 215 GPa from digital image correlation in conjunction with uniaxial compression testing, nanoindentation, and an immersion ultrasonic inspection technique. The creep tests were performed at 873 and 973 K over stress levels of 30–125 MPa revealed the dislocation climb as a dominating mechanism. The increase in dislocation density level after creep deformation was determined from XRD and EBSD–KAM maps. The deformation mechanism map for Ni33Co alloy is also developed and validated with the current data.
On the Quantitative Characterization of Weld Microstructures: Noah Kohlhorst1; Govindarajan Muralidharan2; Roger Miller2; Ji-Cheng Zhao3; 1Ohio State Univerity; 2Oak Ridge National Laboratory (ORNL); 3University of Maryland, Department of Materials Science and Engineering
The quality and functionality of welds for use in the various industries are dictated by their mechanical properties which are related to their microstructures and are influenced by the weld processing parameters. Thus, there is a need to quantitatively characterize the microstructure of welds and correlate these to weld processing conditions. In this work, we present a new technique to quantitatively characterize the grain size, grain shape, and grain boundary curvature of welds. We will show that this technique can be used to quantitatively describe the spatial variations in these characteristics as a function of weld processing conditions. *Research sponsored by the United States Department of Energy (DOE) Office of Facilities Management (NE-31) at the Oak Ridge National Laboratory, managed by UT-Battelle, LLC for the U.S. DOE. Support and guidance were provided by Mary McCune of the US DOE. Primary funding was provided by the NASA Science Mission Directorate.
Reference-free Potential Development for Metal-rich Carbides: Tyler McGilvry-James1; Bikash Timalsina1; Nirmal Baishnab2; Puja Adhikari3; Saro San3; Andrew Duff4; Wai-Yim Ching3; Ridwan Sakidja1; 1Missouri State University; 2University of Missouri-Columbia; 3University of Missouri-Kansas City; 4Daresbury Laboratory
Reference-free (RF) MEAMfit code is used to generate many-body Embedded Atom Method (EAM) and Reference-free Modified Embedded Atom Method (RF-MEAM) potentials for a variety of metal rich carbides with an emphasis on the M23C6 and MC phases. Such phases are the key ingredients to strengthening Ni-based Superalloys at the grain boundaries. Transferable potentials are produced by sampling energy, force, and stress tensor information from DFT calculations. The optimized potentials were used to study the thermo-mechanical properties of the carbides. Funding from DOE (NETL) Grant No. FE0031554 (Crosscutting Research Program) is gratefully acknowledged. We also thank NERSC for the supercomputer support.