Determination of mode I dynamic fracture toughness of IM7-8552 composites by digital image correlation and machine learning. (15th February 2019)

• Record Type: Journal Article
• Authors: Cidade, Rafael A.; Castro, Daniel S.V.; Castrodeza, Enrique M.; Kuhn, Peter; Catalanotti, Giuseppe; Xavier, Jose; Camanho, Pedro P.
• Is Part Of: Composite structures. Volume 210(2019)
• Page Start: 707
• Page End: 714
• Publication Date: 2019-02-15
• Subjects: Dynamic fracture toughness -- Digital image correlation (DIC) -- J-Integral -- Fiber-reinforced composite materials; Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2018.11.089
• Languages: English
• ISSNs: 0263-8223

Abstract

Abstract: An optical experimental procedure for evaluating the J-Integral from full-field displacement fields under dynamic loading is proposed in this work. The methodology is applied to measure the J-integral in the dynamic compressive loading of fiber-reinforced composites and to calculate the dynamic fracture toughness associated with the propagation of a kink-band. A modified J-Integral that considers inertia effects is calculated over the full-field measurements obtained by digital image correlation, for double edge-notched specimen of IM7-8552 laminates dynamically loaded in a split-Hopkinson pressure bar (SHPB). A sensibility study is conducted to address the influence of the speckle parameters. The results show good agreement with experimental observations obtained by using a different data reduction method, suggesting the existence of a rising R-curve for the studied material under dynamic loading. Furthermore, it was noticed that the inertia effect can be negligible, indicating a state of dynamic equilibrium in which quasi-static approaches may comfortably be used.