Flaw inspection of ultrasonic testing by Angle Probes / Halimatun Fazaiana Abdullah

Non-destructive testing is useful to detect internal failure of any material without damaged the material. Nowadays many types of non destructive testing are applied such as radiography, magnetic particle inspection and ultrasonic testing. Ultrasonic testing is one of the best methods of non-destructive testing, where use the frequency above 20 kHz This method are very effectively and excellent to detect crack or flaw in the material by using the small sensor or probe ad detect on the material. In this paper I would use stainless steel as my sample or material. Since there are also many types of flaw may occur like sub surface flaw, root crack, center line crack and lack of root fusion. All that crack can be detected by use all the types of angle probe such at angle 45°, 60° and 70°.that would be use in this paper. Pulse echo technique is the one of technique to detect the flaw where the probe would be link to OSK (oscilloscope).Its the technique using the echo appear on the OSK's screen and simultaneously know the length and the width of the flaw. Its amazing technique can be use engineers and inspector and actually already by them. What this focus is what angle of certain flaw are effectively can be detected. From the result got, the high of the amplitude and the lowest of decibel be use for echo be appear are the best angle for that flaw. It can been seen in chapter 4 for any crack, at 45 degree, have the highest amplitude compare to 60 degree and 70 degree. The most important is since the crack in the internal of the stainless stain is not change and permanently inside the sample, so whether it use the different angle at one sample. The length and width would unchange. It can also can be seen in chapter 4, for example centre line crack at different angle approximately same. Where at 40°, 60°, and 70°, the length are 8.0mm, 8.9mm, and 8.0mm respectively and the width are 6.0mm, 6.0mm and 6.9mm respectively. The main objective this be written are to determine and investigate the best angle could be use to each sample to make sure engineer and research are more easier to done other testing for future.