ABSTRACT
To provide a microstructural basis for evaluating fracture toughness by an indentation test, a new method to analyse three-dimensional (3D) cracking behaviour in beta-SiC is developed. As an example, the effect of ion irradiation on crack propagation was studied. The sequential cutting-out of thinned sections by focused ion beam (FIB) processing around an indentation impression enabled the reconstruction of the 3D behaviour of cracking near the indentation impression. The FIB processing has an advantage in making finely polished thin sections for scanning electron microscopy (SEM)/transmission electron microscopy without damaging the structure near cracks. In the present work, the procedure of cross-sectioning and the results of crack propagation analysis in beta-SiC by SEM inspection are described.
Subject(s)
Image Processing, Computer-Assisted/methods , Microscopy, Electron, Scanning , Ceramics , Equipment Failure Analysis , SiliconABSTRACT
The combination of focused ion beam (FIB) micro-processing and the lift-out technique using the micro pick-up system was applied to the preparation of TEM specimens of irradiated SiC/SiC composites. The deformation caused by microstructural evolution was observed in the pyrolitic carbon interphase, and several helium bubbles and cavities were detected in the CVI matrix.
Subject(s)
Microscopy, Electron, Transmission , Silicon Compounds , Specimen Handling/methods , CeramicsABSTRACT
As a powerful tool to analyse microstructural evolution under irradiation and the interaction of moving dislocations with radiation-induced defects, a focused ion beam (FIB) method was applied to ion-irradiated SiC followed by the nano-indentation test. An FIB method has excellent capability to prepare thin foils from the area of interest with a high accuracy of location and wide flexibility in the sampling direction. These advantages are demonstrated in the application to Si ion-irradiated SiC by transmission electron microscope observation.
