Size effects in elastic-plastic functionally graded materials
arXiv:1807.08170 · doi:10.1016/j.compstruct.2018.07.048
Abstract
We develop a strain gradient plasticity formulation for composite materials with spatially varying volume fractions to characterize size effects in functionally graded materials (FGMs). The model is grounded on the mechanism-based strain gradient plasticity theory and effective properties are determined by means of a linear homogenization scheme. Several paradigmatic boundary value problems are numerically investigated to gain insight into the strengthening effects associated with plastic strain gradients and geometrically necessary dislocations (GNDs). The analysis of bending in micro-size functionally graded foils shows a notably stiffer response with diminishing thickness. Micro-hardness measurements from indentation reveal a significant increase with decreasing indenter size. And large dislocation densities in the vicinity of the crack substantially elevate stresses in cracked FGM components. We comprehensively assess the influence of the length scale parameter and material gradation profile to accurately characterize the micro-scale response and identify regimes of GNDs relevance in FGMs.
arXiv commentComposite Structures (2018)
References in corpus (10)
- Abaqus2Matlab: A suitable tool for finite element post-processing
- Strain gradient plasticity-based modeling of hydrogen environment assisted cracking
- On fracture in finite strain gradient plasticity
- Strain gradient plasticity modeling of hydrogen diffusion to the crack tip
- Modeling damage and fracture within strain-gradient plasticity
- Numerical analysis of quasi-static fracture in functionally graded materials
- A finite element framework for distortion gradient plasticity with applications to bending of thin foils
- Gradient plasticity crack tip characterization by means of the extended finite element method
- Non-local plasticity effects on notch fracture mechanics
- Elastic-plastic analysis of functionally graded bars under torsional loading