scholarly journals Mode I and II interlaminar critical energy release rates in all-carbon interlayer unidirectional fibre-hybrids based on ultrahigh-modulus and high-strength fibres

2020 ◽  
Vol 236 ◽  
pp. 111886 ◽  
Author(s):  
Sergei B. Sapozhnikov ◽  
Yentl Swolfs ◽  
Stepan V. Lomov
Keyword(s):  
Energy Release ◽  
High Strength ◽  
Critical Energy ◽  
Mode I ◽  
Release Rates ◽  
Energy Release Rates ◽  
Unidirectional Fibre

The Characterization of Mixed-Mode Energy Release Rates in Orthotropic Materials

1996 ◽  
Vol 210 (1) ◽  
pp. 33-42 ◽  
Author(s):  
C A Walker ◽  
Jamasri
Keyword(s):  
Finite Element ◽  
Energy Release Rate ◽  
Energy Release ◽  
Crack Growth ◽  
Release Rate ◽  
Mode I ◽  
Mode Ii ◽  
Finite Element Models ◽  
Release Rates ◽  
Energy Release Rates

The aim of this work was to predict, from the material constants, mixed-mode energy release rates in orthotropic materials, in particular the general cases in which the crack is aligned at a random angle to the principal material direction, normal to the plane of orthotropy. Two-dimensional finite element models with various fibre orientations were generated. The finite element models were validated by comparing two sets of contour plots of deformation, one resulting from the finite element analysis and the other from moiré interferograms of the experimental work. On comparison there was shown to be a strict similarity between experimentally determined and computational deformation fields. Variations of the energy release rates were investigated for both rapid and stable crack growth. This was accomplished by generating two-dimensional stable crack growth finite element models. In general, energy release rates were found to be strongly affected by the fibre orientation. An increase of the angle of the crack growth direction caused a decrease of the mode I energy release rate and, by contrast, an increase of the mode II energy release rate, but the mode II energy release rate was always a small fraction of the mode I value. Crack extension caused a gradual increase of the mode I energy release rate both for coplanar and non-coplanar crack growth. However, there was no significant effect found on the mode II energy release rate.

scholarly journals Geometrically Nonlinear Analysis of Adhesively Bonded Joints

1984 ◽  
Vol 106 (1) ◽  
pp. 59-65 ◽  
Author(s):  
B. Dattaguru ◽  
R. A. Everett ◽  
J. D. Whitcomb ◽  
W. S. Johnson
Keyword(s):  
Energy Release ◽  
Strain Energy ◽  
Strain Energy Release ◽  
Mode I ◽  
Mode Ii ◽  
Geometrically Nonlinear ◽  
Release Rates ◽  
Lap Shear ◽  
Energy Release Rates ◽  
Strain Energy Release Rates

A geometrically nonlinear finite-element analysis of cohesive failure in typical joints is presented. Cracked-lap-shear joints were chosen for analysis. Results obtained from linear and nonlinear analysis show that nonlinear effects, due to large rotations, significantly affect the calculated mode I, crack opening, and mode II, inplane shear, strain-energy-release rates. The ratio of the mode I to mode II strain-energy-release rates (GI/GII) was found to be strongly affected by the adhesive modulus and the adherend thickness. GI/GII ratios between 0.2 and 0.8 can be obtained by varying adherend thickness and using either a single or double cracked-lap-shear specimen configuration. Debond growth rate data, together with the analysis, indicate that mode I strain-energy-release rate governs debond growth. Results from the present analysis agree well with experimentally measured joint opening displacements.

Sign in / Sign up

Export Citation Format

Share Document