SAXS/WAXS experiments using extreme sample environments

By using high intensity synchrotron. radiation X-ray beam lines it is possible to study the structural evolution of materials exposed to extreme conditions like high temperatures, pressure, etc. This possibility creates scope for real time investigations of structural development relevant to manufacturing conditions. The devitrification of glass with the cordierite composition is one of such processes. This process takes place,at temperatures in excess of 1000 degreesC. Combined small and wide angle X-ray scattering experiments have been performed. From these experiments we have been able to derive temperature parameters required to grow monodisperse crystalline particles in an amorphous matrix. By controlling the amount of crystallisation inducing metal ions and the temperature profile the crystalline volume fraction and particle size can be tailored to the required properties. Another example of the use of extreme conditions is the realignment behaviour of smectic-A liquid crystals under the influence of magnetic fields. This is an interesting subject since smectic liquid crystals are thought to be candidates for faster switching devices in for instance liquid crystal displays. The mechanism of reorientation is still not well understood. Time-resolved X-ray scattering experiments in fields up to 10 T will be described. All the results described in this overview have been recently obtained in collaboration with a number of groups. In this text the emphasis will be on the instrumentation aspects of the work and the importance that sample environments can have for experiments in material science. The full results will be published elsewhere. (C) 2002 Elsevier Science B.V. All rights reserved.