Diffraction microcomputed tomography of an Al-matrix SiC-monofilament composite

The structure of an SiC-monofilament-reinforced Al-matrix composite was reconstructed using diffraction rings from these two phases. A 65 keV X-ray beam with 15 mu m width (horizontal) and 150 mu m length (vertical) was scanned across the specimen in 15 mu m steps. A 2 degrees rotation about the vertical rotation axis was used between projections, and filtered back projection reconstructions were created with 15 x 15 mu m in-plane and 150 mu m out-of-plane volume elements (voxels). The integrated intensities of the 11.0, 10.1 and 10.2 SiC and the 111, 200 and 220 Al diffraction rings were used to produce six independent reconstructions. The transmitted-intensity reconstruction agreed with that of higher resolution, absorption-contrast synchrotron microcomputed tomography. The Al reconstructions showed the effect of large grains, and the SiC reconstructions revealed the two microstructural zones in the fibers.