Investigation on the Inspection Technology of GH3535 Alloy Butt Weld With Linear Array Probe

The critical problem to accurately characterizing defects in GH3535 alloy weld is the deflection of the acoustic beam and scattering due to the coarse columnar grains. Signal-to-noise ratio is an important index to indicate whether the grain scattering is severein the ultrasonic inspection. In this paper, the phased array ultrasonic testing of GH3535 alloy butt weld was studied using sector scan mode with linear array probe. The soundfield characteristics of the linear array probe with different focusing parameters were analyzed, and the signal-to-noise ratio in the detection was calculated. The results show that: the acoustic beam of the linear array probe can cover the weld,based on the removal of weld reinforcement. The signal-to-noise ratio of transverse hole with φ3mm located at the weld-fusion lineis more than 15dB, when the front end ofthe probe is located directly above the transverse hole of weld-fusion line.