LAUSR

Abstract The CFETR vacuum vessel (VV) main-body and ports are connected via port stub. For the benefits of deep penetration and small deformation, electron beam welding (EBW) was selected for port stub butt-joint welding. Unacceptable defects such as vertical crack, non-fusion and non-penetration might appear in this kind of large depth-to-width ratio weld. In this paper, the phased array ultrasonic testing (PAUT) method was introduced. Reference blocks with artificial defects of different lengths and heights were fabricated, and then tested by 2.5 MHz 64el dual element matrix array probe and 2.25 MHz 64el single linear array probe. Detection sensitivity of 0.2 mm in width was achieved. In the end, the above probes were successfully applied on the detection of the EBW testing blocks with natural defects. The testing results of reference and testing blocks implied the full capability of the selected probes.