This year the National Educator's Workshop (NEW:Update 2005) was held October 16-19, 2005 at NIST and the University of Maryland. 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 sponsored by NASA-Langley, the Air Force Office of Scientific Research, MSEL (NIST), Norfolk State University, University of Maryland, The Boeing Company, BIMat (NASA), TiiMS (NASA), the National Institute of Aerospace, and ASM Materials Education Foundation.
Implementation of the Ferguson and Stoebe's "Hysteresis Loops and Barkhausen Effects in Magnetic Materials"
By: Mike Meier and Mei Lin Chan
A paper presented at the NEW workshop in 1996 described an interesting and economical experiment where one could obtain the B-H curves for magnetic materials. This paper describes an implementation of this experiment which uses an inexpensive USB-based digital oscilloscope to record the B-H curves which can then be analyzed using spreadsheets. In addition, the circuit boards, mechanical drawings, and parts lists will be available from our web site for anyone who wants to build this equipment themselves.
Note - I was not able to complete the final version of the hardware before leaving UCD. If I ever get a chance to complete the work I'll make the drawings and circuit designs available here.
Click here to view the paper or right-click and "Save As" to download it.
Measuring Crystallite Size Using X-ray Diffraction, The Williamson Hall Technique
By: Mike Meier
With the current interest in nanomaterials it is nice to have an experiment where students can experience nanomaterials themselves. A basic procedure in nanotechnology is determining the size of nanocrystalline materials and there are several x-ray diffraction-based methods available for this. One, the Williamson-Hall technique, is a straight-forward implementation of the Scherrer size where broadening due to strain can also be taken into account. This paper presents an experiment that utilizes the Williamson-Hall technique. The data collection is fairly routine and the data analysis is just challenging enough to make it interesting for the students. Data from this experiment will also be available for downloading, for those who don't have access to a diffractometer, a spreadsheets-based tutorial has also be developed based on this experiment.
- Paper - Click here to view the paper or right-click and "Save As" to download it.
- Data - Click here to download the data for the micron-size powder.
- Data - Click here to download the data for the nano-size powder.