Issue 41

P. Lopez-Crespo et alii, Frattura ed Integrità Strutturale, 41 (2017) 203-210; DOI: 10.3221/IGF-ESIS.41.28 209 3. A outer radius of at least the size of the plastic zone was needed. 4. Little advantage was obtained by excluding the plastic zone. 5. To get accurate results the number of data points/number of terms should be φ ≥40. Of course in our case the plastic zone is not especially well developed (i.e. it is still well within the LEFM regime) different conclusions may apply in the case of extensive plastic deformation local to the crack. A CKNOWLEDGEMENTS he authors would like to acknowledge financial support of Junta de Andalucía through Proyectos de Excelencia grant reference TEP-3244, Campus de Excelencia Internacional del Mar (CEIMAR) and Ministerio de Economía y Competitividad through grant reference MAT2016-76951-C2-2-P. PJW acknowledges European Research Council Funding (CORREL-CT grant number 695638 and EPSRC Funding under the following grants EP/M010619, EP/K004530, EP/F007906, EP/F028431 and EP/I02249X/1. The authors are also grateful to the ESRF for ID15 beamtime awarded under MA-1483. R EFERENCES [1] Nurse, A.D., Patterson, E.A., Determination of predominantly mode II stress intensity factors from isochromatic data. Fatigue and Fracture of Engineering Materials and Structures, 16 (1993) 1339–1354. [2] Nicoletto, G., Experimental crack tip displacement analysis under smallscale yielding conditions. International Journal of Fatigue, 8 (1986) 83–89. [3] Diaz, F.A., Yates, J.R., Patterson, E.A., Some improvements in the analysis of fatigue cracks using thermoelasticity. International Journal of Fatigue, 26 (2004) 365–376. [4] Shterenlikht, A., Díaz-Garrido, F.A., Lopez-Crespo, P., Withers, P.J., Patterson, E.A., Mixed Mode (KI + KII) Stress Intensity Factor Measurement by Electronic Speckle Pattern Interferometry and Image Correlation, Applied Mechanics and Materials, 1-2 (2004) 107–112. [5] Yoneyama, S., Morimoto, Y., Takashi, M., Automatic evaluation of mixed-mode stress intensity factors utilizing digital image correlation, Strain, 42 (2006) 21–29. [6] Lopez-Crespo, P., Shterenlikht, A., Patterson, E.A., Withers, P.J., Yates, J.R., The stress intensity of mixed mode cracks determined by digital image correlation, Journal of Strain Analysis for Engineering Design, 43 (2008) 769–780. DOI: 10.1243/03093247JSA419. [7] Lopez-Crespo, P., Withers, P.J., Yusof, F., Dai, H., Steuwer, A., Kelleher, J.F., Overload effects on fatigue crack-tip fields under plane stress conditions: surface and bulk analysis, Fatigue and Fracture of Engineering Materials and Structures, 36 (2013) 75–84. [8] de-Matos, P.F.P., Nowell, D., Experimental and numerical investigation of thickness effects in plasticity-induced fatigue crack closure, International Journal of Fatigue, 31 (2009) 1795–1804. [9] Yusof, F., Lopez-Crespo, P., Withers, P.J., Effect of overload on crack closure in thick and thin specimens via digital image correlation, International Journal of Fatigue, 56 (2013) 17–24. [10] Garcia-Manrique, J., Camas, D., Lopez-Crespo, P., Gonzalez-Herrera, A., Stress intensity factor analysis of through thickness effects, International Journal of Fatigue, 46 (2013) 58–66. [11] Camas, D., Lopez-Crespo, P., Gonzalez-Herrera, A., Moreno, B., Numerical and experimental study of the plastic zone in cracked specimens, Engineering Fracture Mechanics, (2017). DOI:10.1016/j.engfracmech.2017.02.016. [12] Withers, P.J., Lopez-Crespo, P., Kyrieleis, A., Hung, Y.-C., Evolution of crack-bridging and crack-tip driving force during the growth of a fatigue crack in a Ti/SiC composite, Proceedings of the Royal Society A Mathematical, Physical and Engineering Sciences, 468 (2012) 2722–1743. [13] Maire, E, Withers, P.J., Quantitative X-ray tomography. International Materials Reviews, 59 (2014) 1–43. DOI: 10.1179/1743280413Y.0000000023. [14] Withers, P.J., Use of Synchrotron X-ray Radiation for Stress Measurement. In: M E Fitzpatrick AL, editor. Analysis of Residual Stress by Diffraction using Neutron and Synchrotron Radiation, London: Taylor & Francis; (2003) 170–189. [15] Lopez-Crespo, P., Mostafavi, M., Steuwer, A., Kelleher, J.F., Buslaps, T., Withers, P.J., Characterisation of overloads in fatigue by 2D strain mapping at the surface and in the bulk, Fatigue & Fracture of Engineering Materials & Structures, 39 (2016) 1040–1048. T