Jeffrey Bunn

Jeffrey Bunn

Position: Lead Instrument Scientist

Instrument: Neutron Residual Stress Mapping Facility

Group: Engineering Materials

Division: Chemical and Engineering Materials Division

Facility: High Flux Isotope Reactor, Spallation Neutron Source

Contact: bunnjr@ornl.gov or (865) 241-6133

Oak Ridge National Laboratories, Oak Ridge, TN

  • NRSF2 Lead Instrument Scientist - Junior Research Associate (2016-present)
  • Postdoctoral Research Associate (2014-2016)


University of Tennessee, Knoxville TN

  • Graduate Research Assistant (2007-2014)


Oak Ridge Associated Universities

  • Summer Intern/ASTRO (Summer 2008)
  • Summer Intern/FaST Program Participant (Summer 2006, Summer 2007)

 

Education

The University of Tennessee - Knoxville, Knoxville, TN
Doctor of Philosophy (Civil Engineering, 2014)

The University of Tennessee - Martin, Martin, TN
Bachelor's of Science (Engineering, 2007)

Research

Jeff Bunn is the lead instrument scientist at the NRSF2 residual stress diffractometer at the High Flux Isotope Reactor. 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 XRD and ND 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 current research interests are in the areas of instrument optics, residual stress in joined parts, and mechanical testing through complex and biaxial loading using neutron scattering and imaging at HFIR an SNS.

My past and current research interests are within applied materials research of engineering materials. Some of the broad research topics I have explored are concerning material responses to complex loadings (biaxial torsion, combined tension and torsion, or proportional loadings) measured by neutron and x-ray diffraction. These responses in which I am interested are lattice strain, texture, and residual stress evolution. I also enjoy working on new data analysis tools for reduction and visualization of the aforementioned data. I have a continued interest in neutron imaging for the purpose of strain, texture and phase in engineering materials.

Selected Publications

Hempel, N., Bunn, J.R., et al. (2017). "Study on the residual stress relaxation in girth-welded steel pipes under bending load using diffraction methods." Materials Science and Engineering: A 688: 289-300.

X. YU, D. TZELEPIS, J. BUNN, A.E. PAYZANT, Z. FENG, ‘Tensile Residual Stress Mitigation Using Low Temperature Phase Transformation Filler Wire in Welded Armor Plates’, Materials Research Proceedings, Vol. 2, pp 461-466, 2017

H. Eisazadeh, J. Bunn, and D. K. Aidun, “Numerical and Experimental Investigation of Residual Stress Distribution in a Dissimilar Ferritic-Austenitic Weld”, Welding Journal, vol.96, no.1, p.21-s (January 2017)

Eisazadeh, H., Bunn, J.R., et al. (2016). "A Residual Stress Study in Similar and Dissimilar Welds" Welding Journal 95(4).

Penumadu, D., et al. (2016). "Damage of Composite Materials Subjected to Projectile Penetration Using High Resolution X-Ray Micro Computed Tomography." Experimental Mechanics 56(4): 607-616.

Cakmak, E., et al. (2016). "Mechanical Characterization of an Additively Manufactured Inconel 718 Theta-Shaped Specimen." Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science 47A(2): 971-980.

Bunn, J. R., et al. (2014). "Effect of Multi-Axial Loading on Residual Strain Tensor for 12L14 Steel Alloy." Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science 45A(9): 3806-3813.

Bunn, J. R., et al. (2013). "Detection of water with high sensitivity to study polymer electrolyte fuel cell membranes using cold neutrons at high spatial resolution." Applied Physics Letters 102(23).

Bunn, J., et al. (2010). "Residual strain evolution in steel samples: tension versus torsion." Applied Physics A 99(3): 571-578.

Lemaster, R. A., et al. (2009). "Grinding Induced Changes in Residual Stresses of Carburized Gears." Gear Technology 26(2): 42-49.​

 

 

Awards, Honors and Memberships

Awarded National Science Foundation (NSF) IMI ANSWER fellowship for travel to ISIS Facility at Rutherford Appleton Labs (U.K.) and BERII Reactor at Helmholtz Zentrum Berlin (Germany).

Awarded NSF IGERT 5-Year fellowship (Ph.D.) as part of University of Tennessee Sustainability Through Advanced Interdisciplinary Research (STAIR) program.