Effect of the Thickness on the Fracturing Behavior of Discontinuous Fiber Composite Structures
Autor: | Sam Douglass, James Davey, Marco Salviato, Seunghyun Ko, Mark E. Tuttle, Jinkyu Yang |
---|---|
Rok vydání: | 2019 |
Předmět: |
Materials science
Tension (physics) Composite number chemistry.chemical_element FOS: Physical sciences Fracture mechanics Physics - Applied Physics 02 engineering and technology Applied Physics (physics.app-ph) Edge (geometry) 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Finite element method 0104 chemical sciences chemistry Mechanics of Materials Aluminium Ceramics and Composites Fracture (geology) Fiber Composite material 0210 nano-technology |
DOI: | 10.48550/arxiv.1903.10539 |
Popis: | In this study, we investigate experimentally and numerically the mode I intra-laminar fracture and size effect of Discontinuous Fiber Composites (DFCs) as a function of the structure thicknesses. By testing geometrically-scaled Single Edge Notch Tension (SENT) specimens a notable structure size effect on the nominal strength of DFCs is identified. As the specimen size increases, the nominal strength decreases. For small specimens, we find a limited size effect with enhanced pseudo-ductility and a strong divergence from Linear Elastic Fracture Mechanics (LEFM). For sufficiently large specimen sizes, the scaling of the nominal strength follows closely LEFM with a strong brittle failure. As the thickness increases, the size effect decreases. We identify the fracture energy and the effective size of the fracture process zone as a function of the thickness of the structure. To do so, we integrate equivalent fracture mechanics and stochastic finite element modeling. Experimentally, we collect the nominal strength of geometrically-scaled Single Edge Notch Tension (SENT) specimens. The numerical stochastic model captures the complex, inhomogeneous mesostructure of DFCs by explicitly generating the platelets. From the integrated analysis, it is found that the fracture energy depends significantly on the structure thickness. It is shown to increase gradually up to 2 mm and saturates after 3 mm to a value of 57.77 N/mm, which is 4.81 times larger than a typical aluminum alloy. |
Databáze: | OpenAIRE |
Externí odkaz: |