Nuclear microbeam study of advanced materials for fusion reactor technology

The Oxford scanning proton microprobe was used to study SiC fibres, SiC/SiC ceramic composites and Be pebbles, which are some of the most important ma terials for fusion technology. For the SiC materials, although the results reveal a high degree of homogeneity and purity in the composition of the fi bres, some grains containing heavy metals were detected in the composites. Rutherford backscattering analysis further allowed establishing that at lea st some of these grains are not on the surface of the material but rather d istributed throughout the bulk of the SIC composites. The two different typ es of Be pebbles analysed also showed very different levels of contaminants . The information obtained with the microbeam analysis is confronted with t he one resulting from the broad beam PIXE and RES analysis. (C) 1999 Elsevi er Science B.V. All rights reserved.