Application research on ultrasonic phased array detection algorithm for austenitic stainless steel with V-groove weld

Abstract

Conventional ultrasonic detection methods are commonly used for detecting austenitic stainless steel weld structure. The anisotropy and inhomogeneity of the weld produces a strong scattering and energy attenuation effect on the acoustic wave. Controlling the accurate focusing of synthetic beams by ultrasonic transducer with multi-array element can be challenging, and difficult in detecting internal defects. A multi-group sequence grain model was established according to the distribution of grain orientation (DGO) in the weld, and then the “Velocity Coefficient K” algorithm was explored and developed, which is capable of quickly determining the acoustic wave propagation in the austenitic stainless steel weld with V-groove weld. By establishing an acoustic ray-tracing model with its analysis, the focusing law can be obtained quickly. The experimental results showed that the proposed algorithm has great effectiveness in detecting the signal-to-noise ratio (SNR) and imaging quality of defects.