Mixed-mode I + III interlaminar fracture of carbon/epoxy laminates

• Published in: Composites. Part A, Applied science and manufacturing Vol. 40; no. 4; pp. 518 - 523
• Main Authors: Pereira, A.B., de Morais, A.B.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-04-2009; Elsevier
• Subjects: A. Polymer-matrix composites (PMCs); Applied sciences; B. Delamination; B. Fracture toughness; C. Finite element analysis (FEA); Exact sciences and technology; Forms of application and semi-finished materials; Laminates; Mixed-mode; Polymer industry, paints, wood; Technology of polymers; A. Polymer-matrix composites (PMCs); Mixed-mode; B. Fracture toughness; C. Finite element analysis (FEA); B. Delamination; Mechanical measurement; Laminate; Mechanical model; Fiber reinforced material; Epoxy resin; Mechanical properties; Experimental study; Mineral fiber; Modeling; Composite material; Fracture toughness; Finite element method; Numerical simulation; Delamination; Fracture mode; Bending test; Carbon fiber
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/j.compositesa.2009.02.003

A new test was developed for measuring the mixed-mode I
+
III interlaminar fracture toughness. The specimen adopted was an 8-point bending plate (8PBP) with a cross-ply lay-up and a mid-thickness edge pre-delamination at the standard 0/0 interface. Finite element analyses (FEA) showed that a wide range of mode mix ratios can be achieved by varying the load point displacements imposed. However, the need of FEA based experimental data reduction and of a relatively complicated fixture are important drawbacks of test developed. Nevertheless, results for carbon/epoxy laminates showed a realistic evolution of initiation
G
c values with the
G
III/
G mode mix ratio.