Experimental determination of the notch stress intensity factor for sharp V-notched specimens by using the digital image correlation method

Abstract

Digital image correlation (DIC) method is used to experimentally determine the notch stress intensity factor for sharp V-notched samples under mode I loading conditions. First, two well-known test specimens, namely the single edge notch tension (SENT) and the single edge notch bending (SENB) specimens are chosen. The specimens are made of Polymethyl-methacrylate (PMMA) and for each specimen, five different notch opening angles are considered. Then, the experimental displacement fields in the specimens are derived by using DIC method. Afterward, the over-deterministic method is employed to derive the mode I notch stress intensity factors for the samples tested. According to the over-deterministic method, the analytical displacement field is fitted to a large amount of experimentally obtained local displacement values. Finally, the results obtained from DIC are compared with the results available in the literature. The good accuracy of the results obtained demonstrates the ability of DIC method in derivation of the stress field for sharp V-notched structures.