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An improved photoelastic visualisation system has been developed. A brief description of the equipment is made and a video is prepared for publication on NDT.net. Basic principles of a 5MHz compression wave pulse are illustrated in the video. An NDT.net video collection is planned.

To meet the inspection requirements, all ultrasonic (UT) probes, used for pressure tube inspection in CANDU reactors, should perform according to specification at various temperatures within range from 200C to 500C. However, temperature variations affect several inspection parameters such as the UT wave incidence, refraction and reflection angles, geometrical parameters of tube, UT pulse trajectory and time-of-flight, probe parameters and other characteristics. All these factors change performance of the UT probes and ability of the inspection system to detect, characterize and size flaws. All UT probes can detect and size calibration notches and meet the inspection requirements within the whole required range of temperatures from 200C to 500C. However, probes do not provide uniform detection sensitivity within this temperature range and do not maintain sensitivity balance between flaws located at the inside and outside tube surfaces.

It is well known the use of ultrasonic waves in weld testing. The most popular ultrasonic techniques are the transversal waves with a single transducer and longitudinal waves for the case of TOFD. One alternative is the use of fundamental Lamb waves with the advantage that they can be used far from the weld. However, the low frequencies associated with these fundamental modes are not suitable for high resolution testing. In this paper the use of overtones modes in weld testing, with high phase velocities were studied. A phase velocity method was used to identify the different Lamb mode echoes obtained from edges, weld and a notch in a 5 mm thickness plate.

With measuring the volume fraction of martensite, the destruction of the samples would be considered. In this work a 304L AISI austenitic stainless steel was rolled from 10 to 80 % reduction then the formation of martensite phase was monitored by X-ray diffraction, image analysis of optical, SEM microscopy and eddy current investigation. Also eddy current was carried out in the wide range of frequencies from 50 to 10000 Hz to figure out the effect of it on structural changes then the outputs were calibrated by XRD. By comparing the data of these methods relationship between them was found to be a function of exponential regression. In spite, some researchers have previously reported a linear relationship.