Kevin J. Hemker


		Faculty


Kevin J. Hemker Associate Professor of Mechanical Engineering Joint Appointment in Materials Science and Engineering Postdoctoral Fellow, École Polytechnique Fédérale de Lausanne, Switzerland, 1990-93 Ph.D. Materials Science and Engineering, Stanford University, 1990 M.S. Materials Science and Engineering, Stanford University, 1987 B.S. Metallurgical Engineering, University of Cincinnati, 1985
Professor Hemker's research interests lie in the areas of high temperature deformation, physical metallurgy, transmission electron microscopy (TEM), and mechanical properties of high temperature structural materials. While at the NASA Lewis Research Center and Stanford University, Prof. Hemker used monotonic and transient mechanical testing to measure and model creep and yielding behavior of Ni-base superalloys and intermetallic alloys. At the École Polytechnique Fédérale de Lausanne, Switzerland, he used high resolution (HREM)weak-beam TEM, and computer-generated image simulations to identify and characterize dislocation core structures at an atomic scale. A large part of Prof. Hemker's current research combines mechanical properties experiments, TEM observations, and image simulations to identify fundamental mechanisms that control deformation in a variety of metals and alloys. In a more general sense, Prof. Hemker is promoting an interdisciplinary teaching and research approach that will give students the tools to bridge the macroscopic, continuum, mesoscopic, microscopic, and atomic length scales that currently bound the physical theories and models that have been developed to describe materials behavior.


		Selected Publications Hemker, K.J. and M.J. Mills. "Measurements of Antiphase Boundary and Complex Stacking Fault Energies in Binary and B-doped Ni3Al Using TEM." Phil Mag A, 68 (1993): 305. Viguier, B., K.J. Hemker, J. Bonneville, F. Louchet and J.L. Martin. "Modeling the Flow Strength Anomaly in Gamma TiAl. Part I: Experimental Observations of Dislocation Mechanisms." Phil Mag A, 71(1995):1295. Viguier, B. and K.J. Hemker. "Characterizing Faulted Dipoles in Gamma TiAl." Phil Mag A, 73 (1996): 575.		Hemker, K. J. "Correlating Dislocation Positions with Intensity Peaks in Weak-beam TEM Images." Phil Mag. A, 76 (1997): 241. Lu, M. and K. J. Hemker. "Intermediate Temperature Creep Properties of Gamma TiAl." Acta Materialia, 45 (1996): 3573. Chichili, D., K. T. Ramesh and K. J. Hemker. "Deformation mechanisms associated with high rate deformation of alpha Ti." Acta Materialia (1996): in press. Kumar, M. and K. J. Hemker. "Dislocation core dissociation in the intermetallic Al3Ti." J. of Materials Research (1996): in press. Lu, M. and K. J. Hemker. "The influence of prestrain on the flow strength of polycrystalline gamma TiAl." Phil Mag. A (1996): in press. Zupan, M. and K. J. Hemker. "Tensile/compressive properties of single crystal gamma Ti-55.5% Al." Metallurgical and Materials Transactions (1997): in press. Hemker, K. J., M. Lu and M. Zupan. "Deformation Processes and Dislocation Motion in Gamma-TiAl." Structural Intermetallics, Eds, Nathal et al., TMS Publications (1997): 147. Hemker, K. J. and W. D. Nix. "Mechanisms of Dislocation Creep in Intermetallic Alloys of the Ni-Al-Ti System." Structural Intermetallics, Eds. Nathal et al., TMS Publications (1997): 21.