Inspection And Special Transducer For Aerial Special-shaped Structure By Ultrasonic Testing

As the ultrasonic wave have the abilities of high penetrating force, gathering and carrying amount of information and it is easy to implement on-line non-destructive testing and non-destructive diagnosis fast and accurately. So ultrasonic has been used in industry, agriculture, defense, biomedical and scientific research, etc. Ultrasonic transducer, as the ultrasonic emission and echo reception device, is the most important component in the whole process. How to choice and use the transducer have been worthy to research in non-destructive, especially for special shapes and materials, This paper researches the special transducer including piezoelectric chip choice, shape design and impedance matching and uses the Feature Scan Imaging System to get defects and the useful information of materials from ultrasonic echo and get characteristics and defects from the waveform characterized by the amount of for signal extraction and reconstruction, then signal amplitude characteristics of echo in each layer have been showed up and the ultrasonic tomography image have been constituted.The main tasks on the study are as following:For several types of special-shaped structural parts, we analysis of the structural features of acoustic communication theory to design a suitable transducer; study the methods to improve transducer waveforms, the main method is adding backing block to adjust chip waveforms, and to study different ratio to find a suitable preparation of the corresponding ratio of the sound backing, and further by adding matching inductor to get ideal vibration waveform; study the technology of special transducer and method of performance testing; choose the appropriate transducer and ultrasonic testing methods to detect special-shaped structural parts.The study realizes that as following: 1.A study of acoustic backing material for different piezoelectric materials to improve the ultrasonic waveform effectively; 2.it developed self-focusing ultrasonic transducer with high-frequency and wideband narrow pulse, solved the detection to special-shaped components such as the hole; 3.For several kinds of composite materials, stainless steel tube, the defects can be showed by the image reflected in the form of visual defect location and quantification.