International Topical Meeting on Nuclear Research Applications and Utilization of Accelerators

4-8 May 2009, Vienna

Non-Destructive Inspection of SiC_f /SiC Composites Structure

H. Tatlisu¹, F. Hameed¹, A. Hilger², N. Kardjilov², and H. Rauch¹

¹Atomic Institute of the Austrian Universities, Vienna, Austria
²Hahn-Meitner Institut (HMI), Berlin, Germany

Corresponding Author: tatlisu@ati.ac.at

Fiber reinforced ceramic matrix composites are attractive candidate structural materials for fusion power plant because of their light weight, high temperature capability, high strength and toughness. Ceramic matrix composites made especially with silicon carbide matrix and fibers (SiC_f /SiC) are promising for nuclear and fusion technology due to excellent and endurance under high-energy particle, such as neutrons and α particles. Porosity, which is based on the manufacturing process of the SiC_f /SiC composites, is a critical issue in using of the composites in fission and fusion rector. Internal pores mitigate most of the outstanding properties of the SiC_f /SiC composites such as thermal conductivity, high strength and probability radiation stability. The pores in composites are unavoidable and significantly reduce the life time and performance of the composites under harsh environments. The aim of the study is to examine the pore structure and high-temperature induced changes within the SiC_f /SiC composite. By means of non-destructive cold neutron tomography (HMI-Berlin), Xray tomography (HMI-Berlin) and small angle neutron scattering (PSI-Villigen) techniques inner microstructure of the composites have been investigated. The cold neutron and X-ray tomography techniques have been performed in order to gain complementary information for the SiC_f /SiC composites with these methods. X-ray tomography provided information about the microstructure of these samples with high resolution. After heat treatment of the composites at 1300°C, 1400°C and 1500°C for different time the small angle neutron scattering (SANS) measurements have been carried out to understand high-temperature induced pore size changes. The two-dimensional neutron scattering patterns from the composites have been evaluated using sector analysis to determine the structure change over the range 0.002 — 0.35 Å. Scattering curves have been revealed the pore size change at elevated temperature.

The authors have assigned to the International Atomic Energy Agency a non-exclusive, royalty-free licence to publish this paper.

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