Development and Performance Evaluation of Immersion Phased Array Ultrasonic Transducer for Detecting Flaw of Alloy Steel Billet

Abstract

Ultrasonic testing of an alloy steel billet in a steel mill has been conducted by multi single element by multi single element ultrasonic testing. However, single ultrasonic testing method has the problem of coupling errors caused by unstable water coupling law detections also reduced by the ultrasonic angle of incidence because of friction on the guide shoe and the billet surface during continuous inspection. In this study, an immersion phased array ultrasonic testing technique is applied to the billet to solve the problems with signal ultrasonic testing techniques and increase test reliability. To achieve this objective, the immersion array ultrasonic transducer was designed and fabricated by CIVA simulation software, and compared with artificial flaws specimens in the performance test. The performance test results show that the developed immersion phased-array ultrasonic transducer is four times more capable of confirming the signal-to-noise ratio compared with signal ultrasonic testing techniques, and is applicable to automated immersion testing of billets.