The NDT of austenitic stainless steel using ultrasound is difficult because the grains divert the direction of the ultrasound and scatter it. The effect is particularly severe in welds because of the weld grain pattern. Thus reliable ultrasonic measurements are difficult to obtain, and there is a need to improve confidence in sizing defects. Significant research progress was made in the early 1990s in the context of the inspection of civil nuclear power plant, using computer simulation models, but there has been little funding since. This project aims to revisit this topic, exploiting new techniques in multi-path ultrasound signal processing, increased computing power, and growth of array transducer technology. This project is being done in collaboration with Andrew Temple (Visiting Professor at Imperial) who was a key contributer in the earlier proprammes of research in this topic.
Sponsors
EPSRC and RCNDE
References
GD Connolly, MJS Lowe, JAG Temple, SI Rokhlin, "Correction of ultrasonic array images to improve reflector sizing and location in inhomogeneous materials using a ray-tracing model", J. Acoust. Soc.Am., vol 127, 2802-2812, 2010.
GD Connolly, MJS Lowe, JAG Temple, SI Rokhlin, "The application of Fermat's principle for imaging anisotropic and inhomogeneous media with application to austenitic steel weld inspection", Proc R Soc Lond A, vol 465, pp. 3401-3423, 2009.
GD Connolly, MJS Lowe, SI Rokhlin, JAG Temple, "Imaging of defects within austenitic steel welds using an ultrasonic array", in Ultrasonic Wave propagation in Non Homogeneous Media, eds A Leger, M Deschamps, Springer, pp. 25-38, 2009.