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Aircraft fuselage material corrosion problems have been major aviation security issues, which hinder the development
of aviation industry. How can we use non-destructive testing methods to detect the internal corrosion defects from the
outside of the fuselage, to find the hidden safety problems in advance and update the defective equipment and materials,
has great significance for the prevention of accidents. Nowadays, the active infrared thermal imaging technology as a
new nondestructive technology has been gradually used on a wide variety of materials, such as composite, metal and so
on. This article makes use of this technology on an aircraft cargo door specimen to detect the corrosion defects. Firstly,
use High-energy flash pulse to excite the specimen, and use the thermal image processing software to splice the thermal
images, so the thermal images of the overall specimen can be showed. Then, heat the defects by ultrasonic excitation,
this will cause vibration and friction or thermoelastic effects in the places of defects, so the ultrasonic energy will
dissipate into heat and manifested in the uneven temperature of surface. An Infrared camera to capture the changes of
temperature of material surface, send data to the computer and records the thermal information of the defects. Finally,
extracting data and drawing infrared radiation-time curve of some selected points of interest to analyze the signal
changes in heat of defects further more. The results of the experiments show that both of the two ways of heat excitation
show a clear position and shape of defects, and the ultrasonic method has more obvious effect of excitation to the
defects, and a higher signal to noise ratio than the flash pulse excitation, but flash pulse method do not contact the
specimen in the process of excitation, and shows the location and shape of defects in the overall of the specimen has its
advantages.
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