Crack detection in welded material by using pulse echo ultrasonic method / Noramyzura Abdul Kadir

This research were done in order to determine whether the crack can been seen or not by using pulse echo method of ultrasound. Their location, length and depth were determined to proved the existed of discontinuity in the test material. The angle probe with frequency 2 MHz and 4 MHz had used with angle of 45°,60°, and 70°. This traditional ultrasonic testing were done on several stainless steel of welded sample in order to investigate either the signal can be read or not by oscilloscope. From this experiment, the signal can be interpreted although the testing was done by using pulse echo ultrasonic method. Unfortunately, the signal cannot be seen by 70 angle probe with 2 MHz. The crack can clearly detected by using 2 Mhz frequency of probe compared to 4 Mhz of probe. The probe with angle 45° and 60° are the best probe that can easily interpreted the signal on oscilloscope.