Silicon carbide based biomorphic ceramics have been fabricated by the reactive infiltration of molten silicon into carbonaceous performs derived from pyrolysis of wood (African Bubinga). The bulk microstructure and high temperature mechanical properties of these ceramics were studied. These biomorphic ceramics mimic the fibrous microstructure of the wood resulting in high strength and anisotropy. In order to study the anisotropic behavior, bulk material was deformed in compression parallel and perpendicular to the direction of fibers. The compressive strength paralel to fiber direction is 750 MPa at 1100 deg C and decreases to 300 MPa at 1350 deg C. The typical strength perpendicular to fiber direction is 215 MPa at 1100 deg C and 120 MPa at 1350 deg C, respectively. These materials were also joined using the ARCJoinT approach. The microstructure of the joints was studied by scanning electron microscopy and the high temperature strength was measured in compression, with the joint forming 45 deg with the compression axis. The joined specimens had strengths from 373 MPa at 1100 deg C to 146 MPa at 1400 deg C, which are lower than the strength of the bulk material compressed axially but higher than the strength in the perpendicular direction.
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