Abstract
A digital image processing method to analyze the fringes of a modified caustic is described. The experiment is easy to perform and simple, and the image processing technique and detecting system can operate automatically, precisely, and quickly. Recording with two video cameras two sets of caustic images during crack growth, the computers process data with a specified fringe counting algorithm. We obtained two complete sets of data, one providing a full field view of the distribution of stress and the other providing the stress intensity factor.
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Lin, C.S., Chang, RS. Digital image processing of crack growth using a modified caustic set-up. J Nondestruct Eval 15, 61–70 (1996). https://doi.org/10.1007/BF00729135
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DOI: https://doi.org/10.1007/BF00729135