The evaluation of alternating current field measurement (ACFM) response on mild steel surface defect / Ahmad Zubir Zainal Abidin

Alternating current field measurement (ACFM) technique is an electromagnetic inspection method that uses hand-held probes, computerized control, data acquisition and computational model. This technique has been developed for the accurate detection and sizing of defects through coatings and know both the length and depth of the defects. Furthermore, it is more efficient than conventional inspection method for example Ultrasonic Testing (UT), Radiography Testing (RT) and Magnetic Particle Testing (MPT). This research present two case studies where the designing of ACFM calibration block with the difference depths and also to measure the maximum depth of crack on surface material that can be reached at certain condition. The mild steel material is used as sample and the defect surface is tested by using the ACFM technique. Results from the experimentally suggest that ACFM can be an extremely useful method to determine flaw size, but that a knowledge of the limitations of the technique must also be well understood.