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a b s t r a c tTubular Si-infiltrated SiC f /SiC composites composed of an inner cellular ceramic and an outer dense ceramic matrix composite (CMC) skin were fabricated by the electrophoretic deposition of matrix phases followed by Si-infiltration for solar receiver applications in concentrated solar energy. Using a combined replica method with the 3D printing of polymeric inks, 3 types of the inner cellular ceramics were produced to examine the permeability and heat transfer properties depending on their structure. To form a gastight dense skin layer, SiC fibers were layered on the cylindrical cellular ceramics by filament winding. The resulting preforms were infiltrated by electrophoretic deposition with SiC and carbon black particles and then by molten Si at 1550 1C. The fabrication process, resulting microstructure, and oxidation behavior of the composites at 1400 and 1600 1C in air are explained in Part 1. The thermophysical properties will be explained in Part 2. Overall, this hybrid method is a suitable processing technology for fabricating SiC f /SiC-based solar receivers.

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Tyranno SA (SiC-polycrystalline fiber, Ube Industries Ltd.) shows excellent heat-resistance up to 2000 o C with relatively high mechanical strength. This fiber is produced by the conversion process from a raw material (amorphous Si-Al-C-O fiber) into SiCpolycrystalline fiber at very high temperatures over 1500 o C in argon. In this conversion process, the degradation reaction of the amorphous Si-Al-C-O fiber accompanied by a release of CO gas for obtaining a stoichiometric composition and the subsequent sintering of the degraded fiber proceed. Furthermore, vaporization of gaseous SiO, phase transformation and active diffusion of the components of the Si-Al-C-O fiber competitively occur. Of these changes, vaporization of the gaseous SiO during the conversion process results in an abnormal SiC-grain growth and also leads to the non-stoichiometric composition. However, using a modified Si-Al-C-O fiber with an oxygen-rich surface, vaporization of the gaseous SiO was effectively prevented, and then consequently a nearly stoichiometric SiC composition could be obtained.