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Dr. John DeFouw

Originally from Grand Rapids, Michigan, I came to Northwestern University and the Dunand Research Group with an undergraduate degree (BS) in Materials Science and Engineering from Purdue University in West Lafayette, Indiana. At Purdue, I was also a Co-Op student working for a total of 24 months in research and development with a supplier in the automotive industry and did a group senior design project on the heat treatment of cast Ni-based superalloys. I completed my Ph.D. thesis work on the synthesis of superconducting magnesium diboride (MgB2) composites. I also worked on the synthesis of Ni-based foams and bulk metallic glass foams by infiltration of a removable salt pattern.

Magnesium diboride is a superconductor with a critical temperature around 39 K. While this is not as high as the high-temperature cuprate superconductors (Tc well above 100 K) it is higher than other intermetallic superconductors such as Nb3Sn that is used in magnetic resonance imaging (MRI) components. Wires of MgB2 would allow practical application near 20 K, which can be achieved with conventional refrigeration techniques and would not require the expensive liquid He that Nb3Sn requires. However, MgB2 is a brittle ceramic and wires cannot be drawn as with a ductile metal. For this reason, practical wires of MgB2 must be in combination with a ductile metal phase. We study the synthesis of MgB2 in situ both for liquid metal infiltration (reaction of commercial B fibers within liquid Mg to form a Mg/MgB2 fiber composite after solidification) and Powder-In-Tube wire making techniques (MgB2 or Mg + B powder is drawn within a metallic tube to produce a metal wire with MgB2 core).

Research

Synthesis of superconducting magnesium diboride (MgB2) composites.

Education

B.S., Materials Science and Engineering, Purdue University

Contact

e-mail: john.defouw(@gmail.com)

Publications

  1. Marcus L. Young, John DeFouw, Jon D. Almer, Dean R. Haeffner, and David C. Dunand: "Load Partitioning during Compressive Loading of a Mg/MgB2 Composite", accepted for publication in Acta Materialia 2007.
  2. Alan Brothers, Richard Scheunemann, John DeFouw, David Dunand. “Processing and Structure of Open-Celled Amorphous Metal Foams.” Scripta Materialia 52 335 2005.
    PDF
  3. James V. Marzik, Raymond J. Suplinskas, William J. Croft, Warren J. MoberlyChan, John D. DeFouw, and David C. Dunand. “The Effect of Dopant Additions on the Microstructure of Boron Fibers Before and After Reaction to MgB2.” Materials Research Society Symposium Proceedings 848 FF6.2.1 2005.
    PDF
  4. John DeFouw and David Dunand. “In situ synthesis of superconducting MgB2 fibers within a magnesium matrix.” Applied Physics Letters 83 120 2003.
    PDF

Presentations

  1. John DeFouw , David Dunand, John Quintana . “Mechanisms of MgB2 Formation from Reaction of Solid B with Liquid Mg.” Presented to the Spring Meeting of the Materials Research Society (San Francisco, CA) 2006.
  2. Marcus L. Young , John DeFouw, Jon D. Almer, Kamel Fezzaa, Wah-Keat Lee, Dean R. Haeffner, and David C. Dunand, "High Energy X-ray Diffraction Measurements and Imaging of Superconducting Mg/MgB2 Composites under Compressive Loading.” Invited to the Spring Meeting of the Minerals, Metals, and Materials Society (San Antonio, TX) 2006.
  3. Marcus L. Young , John DeFouw, Jon D. Almer, Kamel Fezzaa, Wah-Keat Lee, Dean R. Haeffner, and David C. Dunand: "In-situ Strain and Imaging Measurements of Superconducting Mg/MgB2 Composites under Compressive Loading." Presented to the Denver X-ray Conference (Denver, CO) 2005.
  4. John DeFouw , John Quintana, David Dunand . “Kinetics measurement by in-situ synchrotron diffraction of the reactive synthesis of superconducting MgB2 fiber composites.” Presented to the 107th Annual Meeting of the American Ceramic Society (Baltimore, MD) 2005.
  5. John DeFouw, David Dunand, Jim Marzik, Ray Suplinskas, John Quintana . “Processing, Microstructure, and Properties of Doped and Undoped MgB2 Fibers.” Presented to the March Meeting of the American Physical Society (Los Angeles, CA) 2005.
  6. John DeFouw, John Quintana, David Dunand . “In-situ synchrotron radiation study of reaction kinetics for bulk MgB2 synthesis.” Presented in poster form to the Spring Meeting of the Materials Research Society (San Francisco, CA) 2005.
  7. James Marzik, Raymond Suplinskas, William Croft, Warren MoberlyChan, John DeFouw, David Dunand . “The Effect of Dopant Additions on the Microstructural Characteristics of Boron Fibers.” Presented in poster form to the Fall Meeting of the Materials Research Society (Boston, MA) 2004.
  8. John DeFouw , David Dunand, John Quintana . “In-Situ Synchrotron X-Ray Diffraction Study of Reaction Kinetics for Reactively Processed Mg/MgB2 Metal Matrix Composites.” Presented to the Fall Meeting of the Minerals, Metals, and Materials Society (Chicago, IL) 2003.
  9. Cédric von Grünigen, John DeFouw, David Dunand . “Melt Processing of Superconducting MgB2/Metal Composites.” Presented in poster form to the Fall Meeting of the Materials Research Society (Boston, MA) 2002.

 

 

 

August 7, 2008