Development of a facility for evaluating characteristics of ultrasonic transducers

Non-destructive testing is all about examining materials in such a way that their intended use is not impaired. Of all the NDE techniques, Ultrasonics is the most widely used for its reliability to detect & characterize a wide range of defects in composites during both manufacturing & in-service. To acquire reliable & repeatable ultrasonic inspection results, the center frequency & sensitivity of the transducers is to be determined to ensure there is no change in them due to regular usage. Characterization of ultrasonic transducers is necessary to check for deviations if any from the original characteristics of the transducers, as the analysis and subsequent decision on the inspected components would be directly based on these characteristics. Any deviations in the characteristics would reflect on the measured parameters, as these are highly sensitive to frequency shifts in composite materials. Also, periodic . qualification of transducers would help in generating reliable and repeatable measurements within the acceptable range. Conventionally, transducer characterization in the area of NDT is carried out through pulse-echo technique. In response to the needs of improved quality assurance & reliability of inspection, evaluation of transducers that are in use for inspection was initiated. The objective of the programme was to determine the frequency response & sensitivity of transducers that are in service. This report deals with setting up of a facility for\ud evaluating characteristics of ultrasonic transducers.\u