Al. Highsmith et S. Keshav, QUANTITATIVE ASSESSMENT OF FIBER FRACTURE IN DAMAGED LAMINATES USING X-RAY RADIOGRAPHY, Journal of composites technology & research, 19(1), 1997, pp. 10-19
In this paper, a new technique for extracting quantitative information
about fiber fracture from dye penetrant enhanced X-ray radiographs is
described. In this new inspection method, the observer marks fiber fr
acture zones on a digitized version of the radiograph depicting the da
mage state. Image processing routines are used to isolate the marked f
iber fracture zones, and then extract fiber fracture parameters such a
s the length of the longest fiber fracture zone and the total length o
f fiber fracture from the marked image. The technique has been used to
quantify fiber fracture in graphite epoxy laminates damaged by either
quasi-static contact loading or low-velocity impact. The residual str
engths of these specimens were found to correlate well with the fiber
fracture parameters, with specimens containing more fiber fracture exh
ibiting lower residual strength.