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ENGINEERING 232 - Engineering of Materials

Go to Semester: Spring 2001, Spring 2002, Spring 2003, Spring 2004, Spring 2006

Analytical electron microscopes are used to teach principles of high-precision engineering design and microcharacterization of materials.

Scanning electron microscopy (SEM) of materials.
Below are SEM micrographs of the broken ends of metal slugs of various compositions. The slugs were prepared during a lab session demonstrating mechanical properties of materials using the Instron to stretch the slugs to their breaking point. The SEM reveals that the materials have different microstructure that, in part, accounts for their different behavior under strain.
Brass (below left), Steel (below right)

 

Copper (below left), Aluminum (below right)

 

Transmission electron microscopy (TEM) and X-ray energy dispersive spectroscopy (EDS).
This is an x-ray EDS spectrum from a 200um latex sphere coated with gold, as visualized in the transmission electron microscope, that demonstrates the presence of gold (Au) and copper (Cu). The copper signal arises from backscattered electrons striking the support grid. The background continuum displays the typical contribution from Brehmstrahlung (braking radiation) x-rays. The x-axis displays x-ray energies; the y-axis displays the number of counts per channel.