Phased Array Ultrasonic NDE of Plasma Facing Components

Realizing the promise of nuclear fusion depends in part on effective plasma facing components (PFCs) that can withstand the intense heat loads, forces, and neutron bombardment of long-pulse high-power reactor operation. A single reactor such as ITER will require thousands of PFCs. Because imperfections in the joints of just one PFC could have disastrous consequences for reactor operation, joint quality must be evaluated nondestructively during manufacture. A suitable NDE approach must accommodate the complex geometries of the components, provide 100% inspection of the joints, yield resolutions of one millimeter or less, and operate as part of the manufacturing process. This project will investigate the use of a revolutionary new NDE technique known as phased array ultrasound for the inspection of PFC joints. In Phase I, the feasibility of using phased array ultrasound for inspecting PFCs was demonstrated by: (1) experimental detection of joining defects in representative PFC specimens using phased array transducers; and (2) the design and numerical validation of a more advanced phased array transducer customized to the actual three-dimensional PFC geometry. Phase II will develop a prototype phased array system, appropriate for in-line production inspection of PFCs. Instrumentation capable of driving this advanced system will be developed. The instrument and probes will be demonstrated on PFC mockups representative of the different stages of production. Commercial Applications and Other Benefits as described by the awardee: The NDE system should serve a long-standing unmet need for inspection of dissimilar metal bonds with complex geometry. Such scenarios arise not only in various components of fusion reactors, but also in nuclear fission reactors, petrochemical plants, aerospace vehicles, and manufacturing industries