2017 | AFC ACCOMPLISHMENTS 93 Project Description SiC/SiC composites offer a set of properties that make these mate- rials highly attractive for cladding applications in light water reactors with enhanced accident tolerance. However, the deployment and commercialization of components for nuclear applications manufactured using SiC/SiC composite require several important considerations. Of particular, a qualified database of the properties of SiC/SiC composite will be needed for performing rigorous design qualification. Such qualified database is one which is generated using procedures that comply with standards associated with the design code of the component of interest. The current database of mechanical properties for nuclear grade SiC/SiC composite is limited and inadequate for the purposes stated above. Although various properties of nuclear grade SiC/SiC composites have been measured, tubular test specimens were not used in those studies.The ASTM standard test method for axial tensile properties (ASTM C1773- 13) of continuous-fiber reinforced ceramic composite tubes has been developed only recently.This ASTM standard currently lacks the precision and bias statements which convey important information to the users of the standard about the quality of their test results. The present work fills these gaps in the development process of SiC nuclear fuel cladding technology through coordinating an interlaboratory round robin study on the tensile properties of SiC/SiC tubular specimens with participation of laboratories from government institutions, academia and industry.This interlaboratory study served multiple objectives: 1) understand the statistical properties of prototypical SiC/SiC composite tubes for fuel cladding applications, 2) develop a precision statement for the ASTM C1773 StandardTest Method (Monotonic AxialTensile Behavior of Continuous Fiber-Reinforced Advanced CeramicTubularTest Specimens at AmbientTemperature), and 3) expand the limited database of mechanical properties of SiC/SiC composite tubular structures. Accomplishments An interlaboratory round robin testing program was carried out for the axial tensile properties of SiC/SiC cladding tubes with the architecture prototyp- ical to LWR fuel cladding.The tubular specimens were specifically designed for this interlaboratory round robin Round-robin testing campaign across leading national laboratories helped complete an ASTM standard and establish properties database for SiC/SiC composite fuel cladding.