Jeff R Bunn

Jeffrey R Bunn

Neutron Instrument Scientist

Jeff Bunn is the lead instrument scientist at the residual stress diffractometer (HIDRA) located at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory. He obtained his B.S. in Engineering from The University of Tennessee at Martin in 2007 and his Ph.D. in Civil Engineering from the University of Tennessee at Knoxville in 2014. He first came to ORNL in 2006 as an undergraduate intern working at the High Temperature Materials Laboratory utilizing x-ray and neutron diffraction for strain determination in engineering materials. Following his Ph.D., he returned to ORNL as a postdoctoral research associate in the Chemical and Engineering Materials Division and in 2014 and was hired permanently as an instrument scientist in 2017. His past and current research interests are within applied materials research of engineering materials. Some of the broad research topics he has explored are concerning material responses to complex loadings (biaxial torsion, combined tension and torsion, or proportional loadings) measured by neutron and x-ray diffraction. His researched has been recognized for material responses to joining, such as welding. He also has worked on new data analysis tools for reduction and visualization of neutron and X-ray data. He has a continued interest in neutron imaging for the purpose of strain, texture and phase in engineering materials.

  • Published peer-reviewed articles in the areas of non-destructive characterization of engineering materials using x-rays and neutrons
  • Over 10 years of experience working in a laboratory setting performing non-destructive evaluation
  • Expert in use of neutron and x-ray diffraction for the purpose of residual stress measurements
  • Expert in use of neutron and x-ray imaging (both polychromatic and energy selective) for characterization
  • Worked extensively with industrial users to obtain useful data for use in design
  • Demonstrated ability to effectively communicate scientific output, even to non-scientific audiences
  • Demonstrated ability to work interdependently within a scientific group with various interests and specialties
  • Programming and data reduction expertise with Excel, MATLAB and python

Specific techniques of which I am proficient: XRD, SAXS, CT-Imaging (neutron and x-ray), SANS, Radiography (neutron and x-ray)

(2009-2014) National Science Foundation fellow and IGERT Trainee as part of the University of Tennessee's STAIR program for sustainability

(2015) Invited departmental talk at Colorado School of Mines in the Materials Sciences and Engineering Department

(2016) Invited to speak at the PRCIM9 international meeting in Kyoto, Japan to discuss residual stress measurement using neutrons

(2017) Invited to perform seminar at Clarkson University to detail technique of residual stress mapping using neutrons - specifically in welding

(2017) Recipient of the A.F. Davis Silver medal from the American Welding Society for being the "author of the paper which has contributed the most to the progress of welding in the field of structural design" Paper: Eisazadeh H., Bunn J.R., Aidun D.K., "Numerical and Experimental Investigation of Residual Stress Distribution in a Dissimilar Ferritic-Austenitic Weld", Welding Journal, 96, 1, 21-s (2017).

(2019) Recipient of the A.F. Davis Silver medal from the American Welding Society for being the "author of the paper which has contributed the most to the progress of welding in the field of structural design" Paper: Eisazadeh H., Payzant E.A., Cornwell P.A., Bunn J.R., Aidun D.K., "Exploring the Cooling Process for Residual Stress Reduction in Dissimilar Welds", Welding Journal, 97, (2018).

(2021) Recipient of the A.F. Davis Silver medal from the American Welding Society for being the "author of the paper which has contributed the most to the progress of welding in the field of structural design" Paper: Wu X., Wang Z., Bunn J.R., Kolbus L., Feng Z., Yu Z.Z., Liu S., "Control of Weld Residual Stress in a Thin Steel Plate through Low Transformation Temperature Welding Consumables", Welding Journal, 99, 124-134 (2020).

(2023) Winner of R&D 100 award - Additively Manufactured Thermally Conductive Collimators for Neutron Instrumentation, developed by ORNL and PolarOnyx.

Bachelors in Engineering - 2007 - University of Tennessee, Martin

Ph.D. Civil Engineering - 2014 - University of Tennessee, Knoxville

ASM International

American Welding Society

Society of Experimental Mechanics 

  • Neutron Engineering  Diffractometers (Both Continuous Wavelength and Time of Flight)
  • X-ray Diffraction, Specifically sin2psi for residual stress determination
  • Load frames for mechanical testing of mechanics of engineering materials (multiaxial tension, torsion or combined)
  • LDRD for Creep Electro Static Levitator (CrESL) for determination of micro-mechanical behavior in container-less creep measurement at extreme temperatures (>1200 C)