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Group Alumni

Daniel W. Clark
MS-NE, Aug. 2015; conferred Dec. 2015
Ion Irradiation Characterization Studies of MAX Phase Ceramics

Daniel has a background in nuclear engineering for fission and fusion systems, with a focus on developing materials for these extreme environments.  He was the first member of Steve Zinkle’s research group, joining UTK in the Fall of 2013 after completing his BS degree in Nuclear Engineering from Texas A&M University.  He worked for 8 years as the Fusion Materials Program Manager with the U.S. Department of Energy, Office of Fusion Energy Sciences. He is currently a senior materials scientist with Type One Energy Group, a fusion startup company,. In his spare time, he enjoys playing soccer, traveling, and exploring the great outdoors.

W. Ethan Pratt
MS-MSE, Dec. 2015
Kinetic and Thermodynamic Modeling of Long Term Phase Stability in Alloy 800H Subjected to LWR Core Conditions” (Brian Wirth, coadvisor)

Ethan is currently a Research Associate at Oak Ridge Associated Universities.

Congyi Li

PhD-ESE, August 2018
Characterization of Radiation Effects and Ab Initio Modeling of Defects in a High Entropy Alloy for Nuclear Power Application” (Brian Wirth, coadvisor)

Investigating radiation effects in metals and novel alloys by integrating experimental characterization (TEM, nano-indentation, positron annihilation spectroscopy, thermal desorption spectroscopy, etc) and theoretical modeling (ab initio modeling and cluster dynamics)”

Caleb Massey
PhD-NE, Dec. 2018
Multiscale Investigations of Nanoprecipitate Nucleation, Growth, and Coarsening in ODS FeCrAl Alloys: Optimizing Sink Strength for Nuclear Applications

Caleb Massey received his BS and MS in Mechanical and Nuclear Engineering at Virginia Commonwealth University prior to joining Dr. Zinkle’s group in 2016. At the University of Tennessee, Caleb partnered with Oak Ridge National Laboratory to develop and optimize new nanostructured ferritic alloys for fission and fusion applications. After receiving his PhD in 2018, Caleb joined ORNL as a staff member in the Nuclear Fuel Materials group. His research interests include advanced manufacturing methods, irradiation effects, advanced microscopy, and data mining.

In his free time, Caleb enjoys traveling to new places, teaching group fitness, scotch, grilling, DIY projects, and spending time with friends & family – In no particular order.

Kelsa Benensky

PhD-NE, Jan. 2019; conferred May 2019
Investigation of Refractory Carbide Behavior in Flowing Hydrogen at Very High Temperatures Relevant for Nuclear Thermal Propulsion Applications

Kelsa is a nuclear systems engineer at Analytical Mechanics Associates Inc. who specializes in nuclear space systems. Her professional interests include: high temperature structural and fuels development for advanced nuclear reactor applications, as well as space nuclear reactor design and analysis. In her  free time, she enjoys traveling and hiking around the South East with her husband and their dog, Rolo.

Jamieson Brechtl
PhD-ESE, April, 2019, conferred August 2019
Effects of Irradiation and Annealing on the Microstructures and Mechanical Properties of Bulk Metallic Glass Alloys”

Jamieson currently uses the skills he learned during his doctoral work on a wide variety of technologies and applications for research projects at Oak Ridge National Lab.  In his spare time, he enjoys camping and hiking with his family.

Ling Wang

PhD-MSE, Dec. 2019; conferred May 2020
Phase Stability of Precipitates after Ion Irradiation and Creep Tests

Ling is dedicated to improving our understanding of how structural materials perform in extreme environment by utilizing advanced microstructural characterization to reveal the radiation effects, precipitate stabilities, and correlation between mechanical properties and microstructures in metal alloys. She enjoys building LEGO in her leisure time.

Peter Doyle

PhD-NE, May 2020

Evaluation of the Hydrothermal Corrosion of SiC and the Viability of Mitigation Coatings to Protect SiC Across Typical LWR Chemistry and Temperature Regimes

Peter works to understand materials science problems related to current and emerging nuclear fuels. Currently, he is a Postdoctoral Researcher at Oak Ridge National Laboratory in the Nuclear Fuel Element Performance group.

Elizabeth Lindquist

MS-NE, August 2020

“High Heat Flux Testing Facilities and an Electrothermal-Arc Plasma Source for Plasma-Material Interaction Studies and Diagnostic Development”

Elizabeth earned her B.S. in Physics from Hope College, MI. Since graduating, she has conducted research at Oak Ridge National Lab and joined Dr. Zinkle’s research group in 2017. Elizabeth earned her M.S. in Nuclear Engineering from UTK on building and improving an electrothermal-arc plasma source to deploy new laser diagnostics, digital holography and laser spectroscopy, to measure in situ gross erosion rates of plasma facing components. In her free time, she enjoys science education, classical music, and traveling.

William Ponder

MS-NE, May 2021, conferred Aug. 2021

The Application of Laser Induced Breakdown Spectroscopy to Molten Salt Corrosion

William grew up in Sierra Vista, AZ. He earned his B.S. at UTK in Nuclear Engineering in 2018. William worked in the study of molten salt corrosion under the supervision of Steve Zinkle and Stephen Raiman. Outside of school and research, William is an active Outdoorsman and Piano Player.

Tyler Smith

PhD-MSE, May 2021

Microstructural Investigation of Hydride Reorientation in Zirconium based Spent Nuclear Fuel Cladding

He graduated with Master’s and Bachelor’s degrees in Material Science and Engineering from the University of Tennessee and the University of North Texas, respectively.

His research was  conducted at the Irradiated Fuels Examination Laboratory (IFEL) and Low Activation Materials Design and Analysis Laboratory (LAMDA) at ORNL and focused on the synergistic effects that influence hydride reorientation in spent nuclear fuel cladding. He will be working on metal hydrides as a postdoc at Los Alamos National Lab starting in the Fall of 2021.

C. Joshua Beers

PhD-ESE, August 2021, conferred Dec. 2021

“Impurity Production and Transport in the Prototype Material Plasma Exposure eXperiment

Clyde Joshua Beers received an M.S. degree in Nuclear Engineering and Radiological Science from the University of Michigan.

His work as a graduate research assistant at the University of Tennessee involved fusion relevant material exposures on the linear plasma device Prototype-Material Plasma Exposure eXperiment (Proto-MPEX) at Oak Ridge National Laboratory. His  research topics were near target plasma characterization and ceramics and refractory metal surface morphology changes under ITER divertor relevant plasma exposures. Josh is currently a staff member at Zap Energy in the Seattle area.

Adrien Terricabras

PhD-ESE, August 2021, conferred Dec. 2021

“Ion Irradiation Studies for the Development of Novel Nuclear Fuels”

Adrien graduated with an A.S. in Materials Science and Engineering from the Nîmes Institute of Technology (France), studied Chemical Engineering during his third year at the University of the West of Scotland (UK) and received a M.S. in Radiochemistry and Nuclear Materials Science from the University of Montpellier (France).

His work focuses on ion irradiation effects on advanced nuclear fuels, specifically on high thermal conductivity nuclear fuel surrogates and nitride coatings for TRISO fuel application. He enjoys photography and badminton in his spare time.

He is working on nuclear fuels R&D as a postdoc at Los Alamos National Lab.

Yan-Ru LinYan-Ru Lin

PhD-MSE, December 2021

Thesis title: “Fundamentals of Cavity Formation in α-Fe and Fe-Cr Alloys

Yan-Ru grew up in Taiwan and graduated with a B.S. and M.S. in materials science and nuclear engineering from National Tsing Hua University. While at UTK, studied microstructural evolution of helium bubbles in Fe-Cr and nanostructured alloys. Beyond radiation damage in nuclear materials, he enjoys mixed martial arts. He is currently a postdoctoral research associate at Oak Ridge National Lab.

Taylor Duffin

PhD-NE, May 2022

Thesis title: “Corrosion and Microstructural Characterization of Molybdenum-YSZ Cermets Following Hydrogen Exposure up to 2630 K

Taylor Duffin is a Ph.D. graduate of the University of Tennessee. His research focuses on nuclear thermal propulsion to enable a human mission to Mars. He studies molybdenum cermet fuel materials for the nuclear rocket, specifically their high temperature behavior in a hydrogen environment. He received a Master’s in Nuclear Engineering from Penn State in 2017 and a Bachelor’s in Chemical Engineering from the University of Utah in 2015. He also competes in tournaments playing the Pokemon card game. He is currently a staff member with X-Energy.

Michael Pagan

PhD-NE, May 2022

Thesis title: “Effects of Plastic Deformation from Ultrasonic Additive Manufacturing

Michael Pagan grew up in west Tennessee, and he earned his B.S. in Material Science and Engineering at the University of Tennessee. He worked on his Ph.D. in Nuclear Engineering, co-mentored by Dr. Zinkle and Dr. Babu, researching dissimilar metal interfaces and advanced structural materials. In his free time, Michael enjoys running, hiking, and playing video games.  He is currently a postdoctoral research associates at Georgia Tech.

Neal Gaffin

PhD-NE, August 2022, conferred Dec. 2022

Thesis title: “Fabrication, Thermophysical, and Mechanical Properties of Cermet and Cercer Fuel Composites for Nuclear Thermal Propulsion

Neal Gaffin was born and raised in Las Vegas, Nevada. He received a B.S. in Chemical Engineering from Brigham Young University and a M.S. in Materials Science and Engineering from the University of Tennessee – Knoxville. He works with spark plasma sintering to fabricate, characterize, and test high-temperature composites for use in nuclear thermal propulsion. In his free time, he enjoys photography and hiking with his wife, son, and daughter. He is currently a staff member with Ultra Safe Nuclear Corporation

Yajie Zhao
PhD-MSE, December 2022, conferred May 2023

Thesis title: “Kinetics and phase stability of nano-scale precipitates in Fe-based binary alloys during ion irradiations”

Yajie Zhao is from China and joined Dr. Zinkle’s research group in the Fall 2016. She graduated with a B.S degree in materials science and engineering from the University of Science and Technology Beijing. Her PhD research focused on the formation of Cr-enriched alpha prime precipitates in Fe-Cr alloys after heavy ion irradiation. She is currently employed at Oak Ridge National Laboratory.

Pengcheng Zhu
PhD-NE, May 2023

Thesis title: “Microstructure Evolution and Mechanical Response of Thermally Aged and Irradiated Fe-Cr Alloys”

Pengcheng Zhu is from China and joined Dr. Zinkle’s group in 2017. His PhD thesis research was focused on the mechanical properties of FeCr alloys under thermal aging and ion irradiation. Before joining UTK, he graduated with a B.S and M.S in nuclear engineering from Huazhong University of Science and Technology, and Shanghai Jiao Tong University, respectively. He is currently employed at Los Alamos National Laboratory.

Samara Levine
PhD-NE, May 2023

Thesis title: “Phase Stability in Nuclear Structural Steels”

Samara was born and raised in New York. She earned a B.S. in Materials Science and Engineering from Virginia Tech in 2013. Following that, she worked at Newport News Shipbuilding on the construction and maintenance of aircraft carriers and submarines until she returned to school at the University of Michigan, where she received a M.S. in Nuclear Engineering and Radiological Sciences in 2019. For her Ph.D. at the University of Tennessee, she researched radiation damage to precipitates and dispersoids in fusion reactor first wall structural steels. Outside of work, Samara enjoys cycling, travelling, and cooking. She is currently employed as a staff member at a fusion energy startup company (Tokamak Energy) near Oxford, England.

Samuel Bell
PhD-MSE, August 2023

Thesis title: “Toward Accelerated Qualification of ATF Claddings: An In-Situ Burst Testing Framework and Insights into Zr Alloy LOCA Behavior”

Sam grew up in southern California and his hobbies include kayaking, skiing, and surfing. He received his bachelor’s degree from UC Santa Barbara where he double majored in physics and earth science. His UTK Department of Materials Science & Engineering PhD thesis research was focused on studying the mechanical behavior and corrosion properties of fuel claddings during loss of coolant. He is currently employed as a research staff member at Oak Ridge National Laboratory.

Brian Ensign
MSNE, August 2023

Project title: “Hydrogen Compatibility of Fuel Element Materials for Nuclear Thermal Propulsion”

Brian Ensign grew up in eastern Iowa and earned a Bachelor of Science degree in Materials Engineering from Iowa State University. His research interests include nuclear and materials science, health and environmental conservation, and energy policy. He is currently working on developing materials solutions for nuclear thermal propulsion. He enjoys kickboxing/MMA, landscaping, and spending time with his wife and children. He is currently employed as a technical professional staff member at Oak Ridge National Laboratory.

Ishtiaque Karim Robin
PhD-MSE, September 2023, conferred December 2023

Thesis title: “A Novel Transition Layer Structure for Integrating Tungsten and Reduced Activation Ferritic/ Martensitic Steel”

Robin was born and raised in Dhaka, the capital of Bangladesh. He earned his B.S. in mechanical engineering from Bangladesh University of Engineering and Technology and his M.S. is in nuclear engineering from Idaho State University. His PhD research focused on structural materials for fusion reactors and advanced manufacturing techniques. Outside of his academic life, his hobbies includes hiking, traveling, and reading book. He is also a chess enthusiast. He is planning to begin working at Pacific Northwest National Laboratory in the Spring of 2024.

Yao Li
PhD-NE, December 2023

Thesis title: “Temperature and Cr effect on dislocation loop formation in ion irradiated Fe and Fe-Cr model alloys”

Yao Li was born and raised in one of the oldest continuously inhabited cities, Xi’an, China. He earned his degrees at Northwestern Polytechnical University (bachelor) and the University of Massachusetts Lowell (Master). In Prof. Zinkle’s group, he studied the effects of Cr, temperature, dose, and dose rate on dislocation loop evolution in Fe-Cr alloys after ion irradiation. His hobby is photography. Starting in February, 2024, Yao will be working at Los Alamos National Laboratory.