Corrosion detection in aircraft by X-ray backscatter methods

A limited-scan backscatter technique for detecting hidden corrosion and oth er flaws in aircraft has been demonstrated. Both simulation and experimenta l results indicate that as little as 5% material loss at depths up to 0.508 cm (0.200 in.) and 10% material loss at depths up to 0.635 cm (0.250 in.) beneath aircraft skin surfaces can be realiably detected. The technology in volves analysis of backscattered photon data to yield a figure-of-merit who se value as a function of position indicates with high probability of detec tion whether or not flaws - such as corrosion, disbonding, macro-cracks, or voids - exist within scanned samples. (C) 2000 Elsevier Science Ltd. All r ights reserved.