An interface-dependent model of plateau fracture toughness in multidirectional CFRP laminates under mode I loading. (15th December 2017)

• Record Type: Journal Article
• Authors: Zhao, Libin; Wang, Yana; Zhang, Jianyu; Gong, Yu; Lu, Zizi; Hu, Ning; Xu, Jifeng
• Is Part Of: Composites. Number 131(2017)
• Page Start: 196
• Page End: 208
• Publication Date: 2017-12-15
• Subjects: Laminate -- Delamination -- Fracture toughness -- Modelling; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2017.07.077
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: Obvious R -curve behavior exists in multidirectional carbon fiber reinforced polymers (CFRP) laminates under mode I loading, in which the plateau fracture toughness represents the steady-state delamination growth behavior. By decomposing the fracture toughness into the fracture work for pure delamination at the interface and that for the intra-ply damage of adjacent layers, a mechanism-based correlation between the plateau value of interface mode I fracture toughness in multidirectional laminates and the interface angle and/or the two angles of the fiber orientations of the two layers surrounding the crack tip was developed, which is an explicitly interface-dependent formula. Static tests were performed on six types of DCB specimen with different interfaces. The analytical calculations agreed well with the experimental data, verifying the proposed correlation. The intra-ply damage and fiber bridging during delamination along different interfaces were evaluated, which provides a justification for the proposed model.