Weld Flaw Detection Using Various Ultrasonic Techniques: A Review

Ultrasonic Flaw Detection by Using Pc Based Correlation Techniques

An on-line random signal flaw detection system was described. It has an increased sensitivity relative to the pulse echo detection system. The system demonstrates random signal correlation and time integration to enhance the signal to noise ratio (SNR). The experimental results show that the range resolution of the system is independent of the signal duration. This allows detection operations w...

Ultrasonic Flaw Detection in Ceramics

Experiments in Ultrasonic Flaw Detection using a MEMS Transducer

In earlier work we developed a MEMS phased array transducer, fabricated in the MUMPs process, and we reported on initial experimental studies in which the device was affixed into contact with solids. We demonstrated the successful detection of signals from a conventional ultrasonic source, and the successful localization of the source in an off-axis geometry using phased array signal processing...

A MEMS Transducer for Ultrasonic Flaw Detection

Metal structures can fail because of fatigue crack propagation or because of section loss from corrosion. Regular inspection is required to intercept such failures, and in situ sensors would be a superior technology for that purpose. We have designed and fabricated arrays of MEMS capacitive diaphragm transducers and we report on their performance as pulse-echo detectors in direct contact with s...

Groundwork for Rail Flaw Detection Using Ultrasonic Phased Array Inspection

An apparent increase in the detectability of certain flaws results when the ultrasonic inspection beam was oriented off the longitudinal axis of railroad rail. Here, artificial reflectors were used to better define the extent of material "seen" by inspection beams, and determine how surface curvature might affect the inspection. Presumably, such information could be useful for suggesting optimu...