Education and professional history
2001-Present: Senior Research Associate, California Institute of Technology
Dr. Rhim is a senior research associate of Caltech Materials Science
Department. He has been using the High Temperature Electrostatic Levitator
(HTESL) measuring properties of refractory materials in their molten
and undercooled states. Working with Professor William Johnson and his
group members he has been measuring various thermophysical properties
and solidification processes of bulk glass-forming alloys. Currently
he is also a principal investigator of a NASA's microgravity material
science program under the title 'Measurement of Thermophysical Properties
of Molten Silicon and Germanium'.
Selected ESL Related Publications
W. K. Rhim, M. Collender, M. Hyson and D. D. Elleman, "Development of an Electrostatic Positioner for Space Materials Processing," Rev. Sci. Instrum. 56(2): 307, 1985
W-K. Rhim, M.T. Hyson, S.K. Chung, M.Colvin , M. Chang, "Containerless Polymeric Microsphere Production for Biomedical Applications," Mat. Res. Soc. Proc. 87: 225, 1987.
W-K. Rhim, S.K. Chung, and D.D. Elleman, "Experiments on Rotating Charged Liquid Drops," Proc. 3rd International Colloquium on Drops and Bubbles, AIP Conf. Proc. 197: 91, 1988.
Won-Kyu Rhim and Sang K. Chung, “Isolation of Crystallizing Droplets by Electrostatic Levitation,” METHODS: (A Companion to Methods in Enzymology) 1(1): 118-127, 1990.
G. Sridharan, W. K. Rhim, D. Barber, and S. K. Chung, “Axial-Gap Induction Motor for Levitated Specimen,” NASA Tech Briefs 16: 32, 1992.
W. K. Rhim, S. K. Chung, D. Barber, K. F. Man, Gary Gutt, A. Rulison, R. E. Spjut. "An Electrostatic Levitator for High Temperature Containerless Materials Processing in 1-g," Rev. Sci. Instrum .64: 2961, 1993.
A. Rulison and W. K. Rhim, "Containerless Measurements of Specific Heat and Hemispherical Total Emmissivity of Refractory Materials" Rev. Sci. Instrum. 65, 695-700, 1994
A. Rulison and W. K. Rhim, "Constant Pressure Specific Heat to Hemispherical Total Emissivity Ratio for Undercooled Liquid Nickel, Zirconium and Silicon" Metall. & Mat. Trans. 26B: 503-508, 1995
R. Busch, Y. J. Kim, W. L. Johnson, A. J. Rulison, W. K. Rhim, and D. Isheim, "Hemispherical total emissivity and specific heat capacity of deeply undercooled Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 melts", Appl. Phys. Letts. 66: 3111-3113, 1995
S. K. Chung, D. Thiessen, and W. K. Rhim, "A Non-Contact Measurement Technique for the Density and Thermal Expansion of Molten Materials,” Rev. of Sci. Instrum. 67(9): 3175-3181, 1996. S. K. Chung, D. Thiessen, and W. K. Rhim, Erratum on "A Non-Contact Measurement Technique for the Density and Thermal Expansion of Molten Materials,” Rev. of Sci. Instrum., 68, 2597, 1997
Y. J. Kim, R. Busch, W. L. Johnson, A. J. Rulison, and W. K. Rhim, "Metallic Glass Formation in Highly Undercooled Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 during Containerless Electrostatic Levitation Processing", Appl. Phys. Letts. 68: 1057, 1996
Y. J. Kim, R. Busch, W. L. Johnson, A. J. Rulison and W. K. Rhim, "Experimental determination of a time-temperature-transformation diagram of the undercooled Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 alloy using the containerless electrostatic processing technique" Appl. Phys. Lett. 68, 1057-1059, 1996
A. J. Rulison, W. K. Rhim, R. Bayuzick, W. Hofmeister, and C. Morton, "Containerless liquid to solid nucleation pathway in two representative grades of commercially available zirconium", Acta Materialia 45(3): 1237-1245, 1997
W. K. Rhim, S. K. Chung, A. J. Rulison, and R. E. Spjut, "Measurements of Thermophysical Properties of Molten Silicon by a High Temperature Electrostatic Levitator", Int. J. Thermophysics 18(2): 459-469, 1997
W. K. Rhim, "Present Status of the Electrostatic Levitation Technology for Containerless Materials Processing", Microgravity Quarterly 6: 79-83, 1997
K. Ohsaka, S. K. Chung, and W. K. Rhim, A. Peker, D. Scruggs, and W. L. Johnson, "Specific volumes of the Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 alloy in the liquid, glass, and crystalline phases", Appl. Phys. Lett. 70 (6), 726-728, 1997.
K. Ohsaka, S. K. Chung, W. K. Rhim, and J. C. Holzer "Densities of Si determined by an image digitizing technique in combination with an electrostatic levitator", Appl. Phys. Lett. 70,423-425, 1997
X. H. Lin, W. L. Johnson, and W. K. Rhim, "Effects of Oxygen Impurities on Crystallization on Undercooled Bulk Glass Forming Alloys", Materials Transactions, JIM. (Japanese Institute of Metal), 38, 473-477, 1997.
K. Ohsaka, S. K. Chung, and W. K. Rhim, "Specific volume and Viscosity of the Ni-Zr alloys and their influence on the undercooling and glass forming capability of the alloys", Acta Materialia 46, 4535-4542, 1998
W. K. Rhim and T. Ishikawa, "Noncontact Measurement of Resistivity of Molten Material", Review of Scientific Instruments, Vol. 69, page 3628-3633, 1998.
W. K. Rhim and T. Ishikawa, "Thermophysical Properties of Molten Germanium Measured by a High Temperature Electrostatic Levitator", Int. J. Thermophysics. 21, 429, 2000.
W. K. Rhim, K. Ohsaka, P-F. Paradis, and R. E. Spjut, "A Non-Contact Technique of Measuring Surface Tension and Viscosity of Molten Materials using Electrostatic Levitation", Rev. Sci. Instrum. 70, 2796-2801, 1999
P-F. Paradis and W. K. Rhim, "Thermophysical Properties of Zirconium at high temperatures", J. Mat. Research 14(9), 3713-19, 1999.
W. K. Rhim and P-F. Paradis, “Laser Induced Rotation of a Levitated Sample in Vacuum”, Rev. Sci. Instrum. 70, 4652-4655, 1999.
W. K. Rhim and K. Ohsaka, "Thermophysical Properties of Molten Silicon Measured by High Temperature Electrostatic Levitation" J. Crystal Growth 208, 313-321, 2000.
P-F. Paradis and W. K. Rhim, " Non-Contact Measurements of Thermophysical Properties of Titanium at High Temperature” J. Chem. Thermodynamics 32, 123-133, 2000.
W. K. Rhim and T. Ishikawa, “Noncontact surface tension measurement by drop rotation” Rev. Sci. Instrum 72,3572-3575, 2001.
Z. Zhou, S. Mukherjee, and W. K. Rhim, “Measurement of thermophysical properties of molten silicon using an upgraded electrostatic levitator” J. Crystal Growth 257, 350-358, 2003
Mukherjee, Z. Zhou, W. L. Johnson, and W. K. Rhim, “Thermophysical properties of Ni-Nb and Ni-Ni-Sn bulk-glassforming melts by containerless electrostatic levitation processing” J. Non-Cryst. Solids (accepted for publication)
Mukherjee, Z. Zhou, J. Schroers, W. L. Johnson, and W. K. Rhim, “Overheating threshold and its effect on Time-Temperature-Transformation diagrams of zirconium based bulk metallic glasses” Appl. Phys. Letts. (submitted)
Mukherjee J. Schroers, , Z. Zhou, W. L. Johnson, and W. K. Rhim, “High temperature viscosity and specific volume of bulk metallic glasses and their correlation with glassforming ability” Acta Met. Materialia (to be submitted)
W. K. Rhim, J. Schroer, S. Bossuyt, J. Li, Z. Zhou, and W. L. Johnson,
“Achievement of uniform temperature of a levitated spherical sample
by tetrahedral laser heating” Rev. Sci. Instrum. (to be submitted)
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