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Current News and Honors
Judi Cockrum retires from the MEEP department
Viscoelastic Effects in Glass Fiber Drawing
By
Dr. William Schultz
J.W. Chen Lecture
Monday, September 10th, 2007
Mechanical Engineering & Energy Processes
Dr. Dale E. Wittmer, Dr. Asghar Esmaeeli, Dr. William W. Schultz, Dr.’s H. Lin and Juh W. Chen
Dr. William Schultz is presently the director of the Fluid Dynamics program under the Chemical, Engineering, Environmental, and Transport Systems (CBET) directorate of National Science Foundation. He received his Ph.D. from Northwestern University in 1982 in the area of Applied Mathematics and Engineering Sciences and has had positions at FMC Corporation, Owens-Corning Fiberglas Corporation, Rutgers University before coming to the University of Michigan Department of Mechanical Engineering where he has been there for the past two decades. Dr. Schultz's area of expertise is very broad and covers subjects such as wave dynamics, fluid structure interactions, theoretical and numerical methods. He has published numerous archival papers and his research has been supported by national funding agencies such as NSF, ONR, and NASA. Prof. Schultz is an ASME fellow.
Abstract: Draw resonance is a common phenomenon that causes undesirable feedback between the winder at the end of the process and the flow near the nozzle resulting in fiber diameter variations. However, draw resonance occurs less frequently than that predicted by previous models. Another unexplained phenomenon is why the ultimate tensile strength (UTS) is one to two orders of magnitude higher in glass fibers than in bulk glass. We show that viscoelastic effects can describe draw resonance inhibition and the attainment of high UTS in glass fibers. Interestingly, this can happen as a modeling post-processing step of Newtonian model and so the typical one-dimensional model is still valid. We also show glass is not thermo-rheologically simple and present a two-component Jeffrey model that shows some promise in modeling fiber spinning.
More Banquet Photos
 
 
SIUC scientist helps Caterpillar study ergonomics
SIUC professor has article published in NASA Tech Briefs
In-Situ Electron Microscopy Testing of Nanostructures
Presented by
Dr. Horacio D. Espinosa
Department of Mechanical Engineering
Northwestern University, Evanston, IL
Abstract: Over the past decade, there has been a substantial thrust to reduce the size of electronic and electromechanical systems to the nano scale by fabricating devices out of thin films, carbon nanotubes (CNTs) and nanowires (NWs). In these applications, a thorough understanding of material mechanical, electrical and thermal properties as well as device performance and reliability requires the development of novel experimental approaches. In this seminar, two such experimental methodologies will be introduced and discussed. The first one addresses the development of MEMS devices for in-situ electron microscopy mechanical testing of thin films and one dimensional (1-D) nanostructures. The design, microfabrication and operation of a MEMS based nanoscale material testing system (n-MTS) will be presented. Results obtained from in-situ SEM and TEM tensile testing of NWs and CNTs will be discussed. The second experimental methodology addresses the in-situ SEM testing of NEMS to assess device electro-mechanical performance (pull-in voltage, I-V curves, and time response) and reliability. A carbon nanotube NEMS bistable switch with feedback control, developed in our lab, will be used to demonstrate the method and highlight present and future research challenges.
About the speaker: Horacio D. Espinosa is Professor of Mechanical Engineering at Northwestern University. He received his undergraduate degree in Civil Engineering from the Northeast National University, Argentina, his M.Sc. in Structural Engineering from Politecnico di Milano, Italy, and his Ph.D. in Applied Mechanics from Brown University, in 1992. He subsequently joined the Purdue University faculty and later moved to Northwestern University in 2000. He has made contributions in the areas of dynamic failure of advanced materials, micro and nanomechanics. He has published over 150 technical papers in these fields. Professor Espinosa has received numerous awards and honors recognizing his research and teaching efforts, including two Young Investigator Awards, NSF-Career and ONR-YIP, the American Academy of Mechanics (AAM) 2002-Junior Award, the Society of Engineering Science (SES) 2007 Junior Medal, and recently the Society of Experimental Mechanics 2005 Hetenyi Award (Best Paper of the Year Award). He is also a Fellow of the AAM and ASME. He was the editor of Mechanics, a publication from AAM, and currently serves as Editor-in-Chief of the Journal of Experimental Mechanics, and Associate Editor of the Journal of Applied Mechanics. His research interests are on size scale plasticity and fracture of nanostructures, MEMS and NEMS, in-situ electron and atomic probe microscopy testing of nanostructures, and the development of devices for massively parallel atomic probe microscopy writing with chemicals and bio-molecules.
At the International 2007 ASME Graduate Student Research and Innovations Conference held in Tulsa, OK, our graduate student, Mr. Serdar Celik won one of the best paper awards. The award includes a certificate and the sum of $200. The paper he presented which was also published in the proceedings of the conference is:
Acoustic Analysis of Flow inside an Evaporator by Celik, S. and Nsofor, E. C.
The 2006 J.W. Chen Lecturer
Dr. Terry N. Tiegs
Senior Distinguished Research Staff (Retired)
Oak Ridge National Laboratory
&
Fellow of the American Ceramic Society
Seminar:
Development of a Family of Ceramic-Metal Composites Through Collaborative Research
Abstract: In the 1980’s, ordered intermetallics were researched because of their excellent mechanical properties and based on those studies, intermetallic bonded ceramic (IBC) composites have been developed over the last 15 years to further improve mechanical and physical properties. In this time period, these composites have evolved from laboratory testing to pilot-plant production for commercial applications. The development path included scoping of the initial property envelope, studies to understand the microstructure/property relationships, scaling up fabrication for cost-effective fabrication, and finally prototype testing. The development effort has been a collaborative one involving a national laboratory, a university, an industrial manufacturer, and an end-user. In particular, Southern Illinois University has been a strong collaborator in this endeavor and several students have based their thesis research on IBC composites. Much like the initial intermetallic research leading to development of IBC composites, SIU has applied this earlier research for a new innovation of intermetallic bonded diamond composites.
Dale E. Wittmer, Chair Dean Emeritus J. W. Chen Dr. Terry N. Tiegs Dean William Osborne
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