Comparison Between Reliability, Sensitivity and Accuracy of Nondestructive Inspection Methods

摘要

A number of inspection methods in frequent use were applied to one hundred aluminium specimens fabricated purposely by the NLR, as well as to more than 220 rejected steel components of real aircraft undercarriages. It is shown that there exists a fair amount of scatter between the results of different techniques and inspectors and also between subsequent inspections by one inspector. Corrosion has a significant influence on reliability, sensitivity, and accuracy. The results of the ultrasonic inspections turn out to be rather disappointing, whereas the results of penetrant inspections tend to depend rather heavily on the specimen configuration. Fluorescent penetrant performs far better than red penetrant. Eddy current gives good moderate results. On the steel components fluorescent magnetic ink as well as magnetic rubber achieve by far the best results, at the penalty of a fair amount of spurious indications.