Study of the stress intensity factors in the bulk of the material with synchrotron diffraction

Lopez-Crespo et al (July 2017) Fatigue 2017 EIS 1 Study of the stress intensity factors in the bulk of the material with synchrotron diffraction P. Lopez-Crespo * , J. Vazquez-Peralta * , C. Simpson ‡ , B. Moreno * , T. Buslaps ¥ , P. J. Withers ‡ * Department of Civil and Materials Engineering, University of Malaga, C/Dr Ortiz Ramos, s/n, 29071 Malaga, Spain ‡ School of Materials, University of Manchester, Oxford Road, Manchester M13 9PL, UK ¥ ESRF, 6 rue J Horowitz, 38000 Grenoble, France A BSTRACT . In this work we present the results of a hybrid experimental and analytical approach for estimating the stress intensity factor. It uses the elastic strains within the bulk obtained by synchrotron X-ray diffraction data. The stress intensity factor is calculated using a multi-point over-deterministic method where the number of experimental data points is higher than the number of unknowns describing the elastic field surrounding the crack-tip. 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