Prof. William L. Johnson
William L. Johnson is the Ruben and Donna Mettler Professor of Materials Science at Caltech. He received his B.A. in physics from Hamilton College and his Ph.D. in applied physics from Caltech. He spent two years at IBM's Thomas J. Watson Research Center (1975-77). He held a Visiting Professor appointment at the Metal Physics Institute in Göttingen, Germany (1983) and received a Von Humbolt Distinguished Scientist Fellowship in Göttingen (1988). He is the 1995 recipient of the TMS/AIME Hume Rothery Award for his experimental work.
Professor Johnson served on the editorial board of the Journal of Rapid Solidification, and serves currently as an associate editor for Journal of Applied Physics, and Applied Physics Letters. He is a principal editor of the MRS Journal of Material Science. He is author or co-author of over 230 publications in the scientific literature, and has contributed to chapters in seven books. He has held numerous consulting positions for the Department of Energy, NASA, and corporations.
Prof. Johnson's research group makes fundamental studies of materials far from equilibrium. This includes synthesis, processing, and characterization of such materials. Materials of particular interest include:
Past work included studies of the crystal to glass transformations, mechanically alloys, nanophase materials, ion solid interactions, and materials processing by rapid solidification methods.
Recent work focuses on the study of "bulk" metallic glass forming alloys. The group has developed several families of metallic alloys which exhibit unusual ability to form glass. These materials can be cast as monolithic glass samples. They carry out research on the glass forming liquids. Studies of viscosity, flow, atomic diffusion, surface tension, and crystal nucleation in the undercooled melt are performed. Fundamental studies of the glass transition and thermal properties of the liquid and glassy state are done.
Characterization techniques employed include x-ray diffraction and small angle x-ray scattering, neutron scattering (in collaboration with IPNS, at Argonne Nat. Lab), field ion microscopy, high resolution TEM, thermal analysis and calorimetry, and containerless processing by electromagnetic and electrostatic levitation of liquids. They participate in flight experiments on liquid alloys aboard the IML-2 and MSL-1 flights of the space shuttle.
The mechanical properties of the monolithic glasses are under investigation. These include measurements of strength, ductility, toughness, and quasi static and dynamic deformation behavior. Collaborative research with faculty in the Applied Mechanics option (e.g. Prof. A.J. Rosakis) is part of this work. Studies of deformation and failure as a function of strain rate are done using high speed imaging and temperature measurement methods. Metallic glass matrix composites have been synthesized in which ceramic reinforcement or ductile metal reinforcement is used to strengthen, toughen, and otherwise improve the engineering properties of metallic glasses. The work includes studies of impact, fatigue, and other important engineering properties of the composites.
Development of casting and processing methods for producing near net shape components of metallic glass is performed. Methods for synthesis of composite materials are explored. This program has a strong emphasis on applications and technology transfer.
A bar of some of the first bulk metallic glass.
FRACTURE-TOUGHNESS AND FATIGUE-CRACK PROPAGATION IN A ZR-TI-NI-CU-BE BULK METALLIC-GLASS
by Gilbert-CJ Ritchie-RO Johnson-WL, APPL-PHYS-L v71 (4) : pp476-478 (1997 Jul 28) Article
CHARACTERIZATION OF BULK METALLIC GLASSES WITH THE ATOM-PROBE
Miller-MK Russell-KF Martin-PM Busch-R Johnson-WL,
J-PHYS-IV v6 (C5) : pp217-222 (1996 Sep) Article
NONCONTACT MODULATION CALORIMETRY OF METALLIC LIQUIDS IN LOW-EARTH-ORBIT
by Wunderlich-RK Lee-DS Johnson-WL Fecht-HJ, PHYS-REV-B v55 (1) : pp26-29 (1997 Jan 1) Article
EVIDENCE OF HEXATIC PHASE-FORMATION IN 2-DIMENSIONAL LENNARD-JONES BINARY ARRAYS
by Li-M Johnson-WL Goddard-WA, PHYS-REV-B v54 (17) : pp12067-12072 (1996 Nov 1) Article
SMALL ATOM DIFFUSION AND BREAKDOWN OF THE STOKES-EINSTEIN RELATION IN THE SUPERCOOLED LIQUID-STATE OF THE ZR46.7TI8.3CU7.5NI10BE27.5 ALLOY
by Geyer-U Johnson-WL Schneider-S Qiu-Y Tombrello-TA et al., APPL-PHYS-L v69 (17) : pp2492-2494 (1996 Oct 21) Article
INCIPIENT CHEMICAL INSTABILITIES OF NANOPHASE FE-CU ALLOYS PREPARED BY MECHANICAL ALLOYING
by Fultz-B Ahn-CC Spooner-S Hong-LB Eckert-J et al., MET-MAT-T-A v27 (10) : pp2934-2946 (1996 Oct) Article
PRECIPITATION OF BCC NANOCRYSTALS IN BULK MG-CU-Y AMORPHOUS-ALLOYS
by Liu-WS Johnson-WL, J-MATER-RES v11 (9) : pp2388-2392 (1996 Sep) Article
BULK METALLIC GLASSES - A NEW ENGINEERING MATERIAL
by Johnson-WL, CURR-OP-SOL v1 (3) : pp383-386 (1996 Jun) Review
INVESTIGATION OF BERYLLIUM DIFFUSION IN THE SUPERCOOLED LIQUID AND GLASSY STATES OF THE AMORPHOUS ALLOY ZR41.2TI13.8CU12.5NI10BE22.5 BY HIGH-ENERGY HELIUM ELASTIC BACKSCATTERING
by Qiu-YX Geyer-U Schneider-S Macht-MP Johnson-WL et al., NUCL-INST-B v117 (1-2) : pp151-155 (1996 Aug) Article
SURFACE MICROSTRUCTURE OF ZR41.25TI13.75CU12.5NI10.OBE22.5, A BULK METALLIC-GLASS
by Lamadrid-MA Oconnor-SD Peker-A Johnson-WL Baldeschwieler-JD, J-MATER-RES v11 (6) : pp1494-1499 (1996 Jun) Article
SUPERCOOLED MELTING IN MULTICOMPONENT ZR-AL-CU-NI DIFFUSION COUPLES
by Busch-R Bakke-E Johnson-WL, APPL-PHYS-L v68 (21) : pp2945-2947 (1996 May 20) Article
EXPERIMENTAL-DETERMINATION OF A TIME-TEMPERATURE-TRANSFORMATION DIAGRAM OF THE UNDERCOOLED ZR41.2TI13.8CU12.5NI10.0BE22.5 ALLOY USING THE CONTAINERLESS ELECTROSTATIC LEVITATION PROCESSING TECHNIQUE
by Kim-YJ Busch-R Johnson-WL Rulison-AJ Rhim-WK, APPL-PHYS-L v68 (8) : pp1057-1059 (1996 Feb 19) Article
THE DYNAMIC COMPRESSIVE BEHAVIOR OF BERYLLIUM BEARING BULK METALLIC GLASSES
by Bruck-HA Rosakis-AJ Johnson-WL, J-MATER-RES v11 (2) : pp503-511 (1996 Feb) Article
FORMATION OF NANOCRYSTALS BASED ON DECOMPOSITION IN THE AMORPHOUS ZR41.2TI13.8CU12.5NI10BE22.5 ALLOY
by Schneider-S Thiyagarajan-P Johnson-WL, APPL-PHYS-L v68 (4) : pp493-495 (1996 Jan 22) Article
FORMATION OF TI-ZR-CU-NI BULK METALLIC GLASSES
by Lin-XH Johnson-WL, J-APPL-PHYS v78 (11) : pp6514-6519 (1995 Dec 1) Article