An order of magnitude makes all the difference

By Birgit Baustädter - In chemical analysis, when electron microscopes reach their limits, the field emission microprobe steps in. With this equipment, taking analysis down to the next level of magnitude is no problem. The wafer-thin black flake shines like a flattened precious stone. The flake is locked in a silver sample container sitting on a clean tray waiting to be pushed into a large machine on the opposite side of the lab. The machine is a field emission microprobe and the sample is a piece of concrete. After being ground with diamond powder and coated with carbon, even something as hum-drum as this takes on a beautiful appearance. Of course, this process is about more than just aesthetic appeal, as Florian Mittermayr of the Institute of Technology and Testing of Construction Materials at TU Graz explains: "We need to prepare our samples meticulously so that they can be accurately analysed." The samples are precisely ground so that their surfaces can be correctly measured.