Ultrasonic guide wave inspection of fillet joints with bend

The paper presentsan ultrasonic guided wave methodology for inspection of a fillet joint with a bend.Owing to the complex shape of the geometry, it is not amenable for conventional techniques. The methodology developed utilizes through-transmission ultrasonic testing. Two 90Δ angle beam (surface wave) ultrasonic transducers of central frequency 2.25 MHz, acting as a transmitter and a receiver are used. A 2.0 mm thick fillet weld joint of SS 304 with rectangular notches,in the weld, of various depths viz. 20% -50% wall thickness (WT) in the range of 0.4 mm – 0.8 mm with 10.0 mm length are considered. The amplitude drop for the notches is compared with that of defect-free locations to evaluate the sensitivity of the technique. The sensitivity of the technique is established to be 0.4 mm deep (20%WT).