NEW:Update 2001

This year the National Educator's Workshop (NEW:Update 2001) was held in College Park, Maryland from October 14-17, 2001.  This workshop gives instructors a chance to share tips, tricks and experiments used in the materials science laboratory courses being taught at universities, community colleges and technical schools and even high schools across north America.  It was organized by Jim Jacobs at Norfolk State University and was sponsored by the NASA-Langley, Norfolk State University, University of Maryland at College Park, MSEL (NIST), and the Department of Energy.


The Onset of Plastic Instability
By: Mike Meier and Amiya K. Mukherjee
This paper describes in detail what happens during a tensile test, how many mechanical properties can be obtained from the stress strain curve, and several methods of predicting/representing the point where deformation becomes unstable (specimen begins to neck). It begins at the start of deformation and covers everything that happen up to final fracture, including methods of determining the value of Young's modulus, criteria for yielding, strain hardening, strain rate hardening, moduli of resilience and toughness, and the onset of necking. The experiment that is done emphasizes doing the tensile test correctly, getting as much data from it as possible, and thinking hard about the conditions that exist when necking begins.

Click here to view the paper or right-click and "Save As" to download it.

Three methods of representing strain hardening.
A plot showing three different strain
hardening behaviors: Hollomon, Ludwick,
and Ludwick with prior strain.

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Lüders Band Formation Video
By: Mike Meier and Aaron Broumas
This paper described the making of a video that shows Lüders bands forming during the tensile deformation of a low-carbon steel.  The video clearly shows something many of us have difficulty describing or illustrating on the blackboard.

In the video shows a polished tensile sample as it is tensile tested.  The first half of the video shows the whole specimen.  The second half zooms in to show in more detail a few Lüders bands growing and branching across the sample.  The specimen was illuminated obliquely, causing it to appear dark with bright edges and with bright Lüders bands.

We have made the smallest format version of the video available from this site. The files for the 640x480 format videos are larger than 150 MB so we won't offer these or the 320x240 format videos here.  If you'd like to have a copy of either of these videos please email us to request one.

This video is no longer available for downloading but you can see it on Vimeo and in the embed above. If you'd like a DVD containing this plus the Underlying Structures videos just drop me an email and I'll send you one.

Click here to view the paper or right-click and "Save As" to download it.

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Acknowledgements
The authors would like to acknowledge Teaching Resources Center and the Department of Chemical Engineering and Materials Science at U. C. Davis for their support in attending the conference.

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