Application of ultrasonic guided waves for non-destructive testing of large and complex geometry engineering structures

Abstract

The wide group of large engineering constructions made from welded metal components and modern composite materials during daily exploitation under non-stationary loads, continuous influence of vibrations and complicated environmental conditions have demand of periodical tests in order to avoid appearance and evolution of the defects. All of them have one common feature - large areas to be tested and the complex geometry. The objective is to improve air-coupled and contact type testing techniques for excitation and reception of appropriate modes of ultrasonic guided waves in large and complex structures. Also, to develop inspection techniques which enable to detect required types of internal defects. The air-coupled and contact ultrasonic techniques for investigation of large and complex geometry objects, such as composites for aerospace applications and petroleum tanks, have been developed. The investigation of propagation effects of ultrasonic guided (Lamb) waves in the plates of the tank floor has indicated relation between reconstructed properties of guided waves and expected presence of corrosion deposits.