Reinforced Radiation Resistant SiC-SiC Composites for Nuclear Reactors and Fuel Cladding
To address the Department of Energy (DOE) need in nuclear-grade silicon carbide (SiC)–SiC composites and methods of joining them to produce complex-shaped components, Physical Optics Corporation (POC), a Mercury Systems company, has developed a new Reinforced Radiation-Resistant SiC–SiC Composites for Nuclear Reactors and Fuel Cladding (RADCOM) technology. RADCOM is based on a unique reinforced and radiation-resistant SiC–SiC composite material fabricated into reactor components using a low-cost manufacturing method: (1) chemical vapor infiltration (CVI) coating SiC onto individual layers of a 2D SiC preform; (2) laying up the fabric on an expandable graphite mold; (3) infiltrating a SiC preform with SiC, yttrium oxide (Y2O3), and TiC using the nanoinfiltration and transient eutectic-phase (NITE) method; and (4) sintering at 25 MPa for densification of the composite to 99% and the formation of in situ SiC whiskers. In Phase IIA, this technology has been optimized to enable future mass production. POC has demonstrated the fabrication of porosity-free, full-density SiC composite material with very high initial thermal conductivity (approximately 100 W/(m·K)), similar to high-grade material fabricated by chemical vapor deposition (CVD). In Phase IIA, POC completed radiation testing of RADCOM components, which produced promising results. The ultimate failure strength (UFS) remained similar before and after irradiation. The irradiated RADCOM material possesses a high room-temperature thermal conductivity of approximately 10 W/m·K, comparable to that of irradiated CVD SiC. The thermal conductivity is a significant advantage of the POC material compared with current nuclear-grade CVI SiC/SiC composites. Using RADCOM joining technology, POC has fabricated and radiation-tested several parts with complex geometries. The joined parts proved to remain consistently robust upon irradiation, with high torsion strength (approximately 100–150 MPa) that was found to actually increase following the part irradiation. Oak Ridge National Lab (ORNL) has concluded that the RADCOM joint technology could be one of the options for the fabrication of SiC-based components for nuclear reactor applications and recommended further development of this technology, specifically for the joining of complex-shaped components, which requires a pressure-less joining technology.
- Research Organization:
- Physical Optics Corporation – A Mercury Systems Company
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- SC0013214
- OSTI ID:
- 1820473
- Type / Phase:
- SBIR (Phase II)
- Report Number(s):
- DOE-POC-0013214; 10186
- Country of Publication:
- United States
- Language:
- English
Similar Records
Freeze Casting SiC-SiC Composites
SiC/SiC Cladding Materials Properties Handbook