Alwyn Eades Research
Professor Eades' interest is in electron microscopy. Although he has worked applying electron microscopy to solving materials problems, his main interests have been in the development of new techniques in microscopy more than in the applications. Transmission electron microscopy has been and continues to be a very powerful tool for the study of materials and this strength arises from the fact that the images obtained can be linked to diffraction information from the same small regions of the specimen. Although he continues to conduct research in transmission electron microscopy (TEM), his current research is also focusing on developing new techniques for diffraction analysis in the scanning electron microscope (SEM). Until recently there were no easy techniques for doing diffraction in the scanning electron microscope. There is now a technique called “electron backscattering diffraction” (EBSD) which makes it possible to find the crystal orientation of specimens in the scanning electron microscope. Professor Eades and his group are working to extend and increase the power of this technique so as to be able to learn more about the sample than just its orientation. If this work is successful the SEM will be able to resolve many classes of materials analysis problems, which currently fall outside its scope.
Convergent-beam diffraction pattern obtained in transmission electron microscopy. The symmetry of such patterns is used to determine the symmetry of the crystal structure of the sample.