Research Interests

• Process-structure-properties relationships in metals and alloys
• Additive manufacturing of metals
• Alloy design
• Dynamic transmission electron microscopy to study materials phenomena with high spatio-temporal resolution
• In-situ techniques in the transmission electron microscope

Ph.D., Materials Science and Engineering, University of California at Berkeley, 2007

M.S., Materials Science and Engineering, University of California at Berkeley, 2003

B.S., Materials Science and Engineering, University of California at Berkeley, 2000

• V. Bathula, C. Liu, K. Zweiacker, J.T. McKeown, J.M.K. Wiezorek, “Interface velocity dependent solute trapping and phase selection during rapid solidification of laser melted hypo-eutectic Al-11at.%Cu alloy,” Acta Materialia 195 (2020) 341.
• R.G. Mariano, A. Yau, J.T. McKeown, M. Kumar, and M.W. Kanan, “Mapping the grain structure of nanoparticles using a scanning electron microscope,” ACS Omega 5 (2020) 2791.
• T. Pinomaa, J.T. McKeown, J.M.K. Wiezorek, N. Provatas, A. Laukkanen, and T. Suhonen, “Phase field modeling of rapid resolidification of Al-Cu thin films,” Journal of Crystal Growth 532 (2020) 125418.
• R. Shi, S.A. Khairallah, T.T. Roehling, T.W. Heo, J.T. McKeown, and M.J. Matthews, “Microstructural control in metal laser powder bed fusion additive manufacturing using laser beam shaping strategy,” Acta Materialia 184 (2020) 284.
• B.W. Reed, A.A. Moghadam, R.S. Bloom, S.T. Park, A.M. Monterrosa, P.M. Price, C.M. Barr, S.M. Briggs, K. Hattar, J.T. McKeown, and D.J. Masiel, “Electrostatic subframing and compressive-sensing video in transmission electron microscopy,” Structural Dynamics 6 (2019) 054303.
• G.H. Campbell, J.T. McKeown, and M.K. Santala, “High-speed electron microscopy,” in Handbook of Microscopy, P. Hawkes and J.C.H. Spence, eds. (New York: Springer, 2019).
• N.J. Ray, J.-H. Yoo, J.T. McKeown, S. Elhadj, S.H. Baxamusa, M.A. Johnson, H.T. Nguyen, W.A. Steele, J.M. Chesser, M.J. Matthews, and E. Feigenbaum, “Enhanced tunability of gold nanoparticle size, spacing, and shape for large-scale plasmonic arrays,” ACS Applied Nanomaterials 2 (2019) 4395.
• R. Shi, S. Khairallah, T.-W. Heo, M. Rolchigo, J.T. McKeown, and M.J. Matthews, “An integrated simulation framework for additively manufactured Ti-6Al-4V: melt pool dynamics, microstructure, solid state phase transformation, and micro-elastic response,” JOM 71 (2019) 3640.
• J.-H. Yoo, H.T. Nguyen, N.J. Ray, M.A. Johnson, W.A. Steele, J.M. Chesser, S.H. Baxamusa, S. Elhadj, J.T. McKeown, M.J. Matthews, E. Feigenbaum, “Scalable light-printing of substrate-engraved free-form metasurfaces,” ACS Applied Materials & Interfaces 11 (2019) 22684.
• Z. Li, T. Voisin, J.T. McKeown, J. Ye, T. Braun, C. Kamath, W.E. King, and Y.M. Wang, “Tensile properties, strain rate sensitivity, and activation volume of additively manufactured 316L stainless steels,” International Journal of Plasticity 120 (2019) 395.
• J.D. Roehling, W.L. Smith, T.T. Roehling, B. Vrancken, G.M. Guss, J.T. McKeown, M.R. Hill, and M.J. Matthews, “Reducing residual stress by selective large-area diode surface heating during laser powder bed fusion additive manufacturing,” Additive Manufacturing 28 (2019) 228.
• J.D. Roehling, A.W. Stokes, D. Bober, G.M. Guss, A. Perron, T.T. Li, J.-L. Fattebert, P.E.A. Turchi, A.J. Clarke, M.J. Matthews, and J.T. McKeown, “Rapid solidification in bulk Nb-Ti alloys by single-track laser remelting,” JOM 70 (2018)1589.
• G.C. Egan, T.T. Li, J.D. Roehling, J.T. McKeown, and G.H. Campbell, “In situ dynamic TEM characterization of unsteady crystallization during laser processing of amorphous germanium,” Acta Materialia 143 (2018) 13.
• A. Perron, J.D. Roehling, P.E.A. Turchi, J.-L. Fattebert, and J.T. McKeown, “Matching time and spatial scales of rapid solidification: Dynamic TEM experiments coupled to CALPHAD-informed phase-field simulations,” Modelling and Simulation in Materials Science and Engineering 26 (2018) 014002.
• K. Zweiacker, C. Liu, M.A. Gordillo, J.T. McKeown, G.H. Campbell, and J.M.K. Wiezorek, “Composition and automated crystal orientation mapping of rapid solidification products in hypoeutectic Al-4at.%Cu alloys,” Acta Materialia 145 (2018) 71.
• Y.M. Wang, T. Voisin, J.T. McKeown, J. Ye, N.P. Calta, Z. Li, Z. Zheng, Y. Zhang, W. Chen, T.T. Roehling, R.T. Ott, M.K. Santala, P.J. Depond, M.J. Mathews, A.V. Hamza, and T. Zhu, “Additively manufactured hierarchical stainless steels with high strength and ductility,” Nature Materials 17 (2017) 63.
• J.D. Roehling, D.R. Coughlin, J.W. Gibbs, J.K. Baldwin, J.C.E. Mertens, G.H. Campbell, A.J. Clarke, and J.T. McKeown, “Rapid solidification growth mode transitions in Al-Si alloys by dynamic transmission electron microscopy,” Acta Materialia 131 (2017) 22.
• J.T. McKeown, K. Zweiacker, C. Liu, D.R. Coughlin, A.J. Clarke, J.K. Baldwin, J.W. Gibbs, J.D. Roehling, S.D. Imhoff, P.J. Gibbs, D. Tourret, J.M.K. Wiezorek, and G.H. Campbell, “Time-resolved in situ measurements during rapid alloy solidification: Experimental insight for additive manufacturing,” JOM 68 (2016) 985.
• J.T. McKeown, L.L. Hsiung, J.-M. Park, H.-J. Ryu, P.E.A. Turchi, and W.E. King, “Size-dependent microstructures in rapidly solidified uranium-niobium powder particles,” Journal of Nuclear Materials 479 (2016) 1.
• K. Zweiacker, J.T. McKeown, C. Liu, T. LaGrange, B.W. Reed, G.H. Campbell, and J.M.K. Wiezorek, “Determination of crystal growth rates during rapid solidification of polycrystalline aluminum by nano-scale spatio-temporal in situ transmission electron microscopy,” Journal of Applied Physics 120 (2016) 055106.
• Verdaguer-Casadevall, C.W. Li, T.P. Johansson, S.B. Scott, J.T. McKeown, I.E.L. Stephens, M. Kumar, M.W. Kanan, and I. Chorkendorff, “Probing the active sites for CO reduction on oxide-derived copper electrocatalysts,” Journal of the American Chemical Society 137 (2015) 9808.
• J.T. McKeown, Y. Wu, J.D. Fowlkes, P.D. Rack, and G.H. Campbell, “Simultaneous in-situ synthesis and characterization of Co@Cu core-shell nanoparticle arrays,” Advanced Materials 27 (2015) 1060.
• G.H. Campbell, J.T. McKeown, and M.K. Santala, “Time resolved electron microscopy for in situ experiments,” Applied Physics Reviews 1 (2014) 041101.
• J.T. McKeown, L.L. Hsiung, H.-J. Ryu, J.-M. Park, P.E.A. Turchi, and W.E. King, “Rapidly solidified U-6wt%Nb powders for dispersion-type nuclear fuels,” Journal of Nuclear Materials 448 (2014) 72.
• J.T. McKeown, A.K. Kulovits, C. Liu, K. Zweiacker, B.W. Reed, T. LaGrange, J.M.K. Wiezorek, and G.H. Campbell, “In situ transmission electron microscopy of crystal growth-mode transitions during rapid solidification of a hypoeutectic Al-Cu alloy,” Acta Materialia 65 (2014) 56.
• S. Mehraeen, J.T. McKeown, P.V Deshmukh, J.E. Evans, P. Abellan, P. Xu, B.W. Reed, M.L. Taheri, P.E. Fischione, and N.D. Browning, “A (S)TEM gas cell holder with localized laser heating for in-situ experiments,” Microscopy and Microanalysis 19 (2013) 470.
• J.T. McKeown, S. Irukuvarghula, S. Ahn, M. Wall, L.L. Hsiung, S. McDeavitt, and P.E.A. Turchi, “Coexistence of the a and d phases in an as-cast uranium-rich U-Zr alloy,” Journal of Nuclear Materials 436 (2013) 100.
• J.T. McKeown, N.A. Roberts, J.D. Fowlkes, Y. Wu, T. LaGrange, B.W. Reed, G.H. Campbell, and P.D. Rack, “Real-time observation of nanosecond liquid-phase assembly of nickel nanoparticles via pulsed-laser heating,” Langmuir 28 (2012) 17168.
• T. LaGrange, B.W. Reed, M.K. Santala, J.T. McKeown, A. Kulovits, J.M.K. Wiezorek, L. Nikolova, F. Rosei, B.J. Siwick, and G.H. Campbell, “Approaches for ultrafast imaging of transient materials processes in the transmission electron microscope,” Micron 43 (2012) 1108.
• N.D. Browning, M.A. Bonds, G.H. Campbell, J.E. Evans, T. LaGrange, K.L. Jungjohann, D.J. Masiel, J.T. McKeown, S. Mehraeen, B.W. Reed, and M.K. Santala, “Recent developments in dynamic transmission electron microscopy,” Current Opinion in Solid State & Materials Science 16 (2012) 23.
• J.T. McKeown, V.R. Radmilovic, R. Gronsky, and A.M. Glaeser, “Silicide characterization at alumina-niobium interfaces,” Journal of Materials Science 46 (2011) 3969.
• D.P. DePonte, J.T. McKeown, U. Weierstall, R.B. Doak, and J.C.H. Spence, “Towards ETEM serial crystallography: Electron diffraction from liquid jets,” Ultramicroscopy 111 (2011) 824.
• J.D. Sugar, J.T. McKeown, V.R. Radmilovic, A.M. Glaeser, and R. Gronsky, “Encapsulation-induced stabilization of dimensionally restricted metallic-alloy wires,” Acta Materialia 58 (2010) 5332.
• J.T. McKeown and J.C.H. Spence, “The kinematic convergent-beam electron diffraction method for nanocrystal structure determination,” Journal of Applied Physics 106 (2009) 074309.
• S.M. Hong, C.C. Bartlow, T.B. Reynolds, J.T. McKeown, and A.M. Glaeser, “Ultrarapid transient-liquid-phase bonding of Al₂O₃ ceramics,” Advanced Materials 20 (2009) 4799.
• J.D. Sugar, J.T. McKeown, T. Akashi, S.M. Hong, K. Nakashima, and A.M. Glaeser, “Transient-liquid-phase and liquid-film-assisted joining of ceramics,” Journal of the European Ceramic Society 26 (2006) 363.
• J.D. Sugar, J.T. McKeown, V.R. Radmilovic, A.M.Glaeser, and R. Gronsky, “Spatially confined alloy single crystals for model studies of volumetrically constrained phase transformations,” Applied Physics Letters 89 (2006) 173102.
• J.T. McKeown, J.D. Sugar, R. Gronsky, and A.M. Glaeser, “Effects of impurities on alumina-niobium interfacial microstructures,” Materials Characterization 57 (2006) 50.
• J.T. McKeown, J.D. Sugar, R. Gronsky, and A.M. Glaeser, “Processing of alumina-niobium interfaces via liquid-film-assisted joining,” Welding Journal 84 (2005) 41.
• J.D. Sugar, J.T. McKeown, R.A. Marks, and A.M. Glaeser, “Liquid-film assisted formation of alumina/niobium interfaces,” Journal of the American Ceramic Society 85 (2002) 2523.
• J. McKeown, A. Misra, H. Kung, R.G. Hoagland, and M. Nastasi, “Microstructures and strength of nanoscale Cu-Ag multilayers,” Scripta Materialia 46 (2002) 593.