Materials Modelling - AE3-409
This course provides additional theory needed for modelling failure of materials in modern high performance structures, e.g. aircraft. Part A of the course covers basic theory and computational approaches for fracture mechanics and fatigue, while part B covers the causes of failure of composite laminates and design methods for such materials.
- The definition of stress intensity factors and energy release rates as fracture criteria.
- The basics of linear elastic fracture mechanics in 2-D and 3-D components, including the Westergaard equations and relationships between the components and fracture criteria.
- The effects of geometry on stress intensity factor, and examples of 2-D and 3-D geometries including mixed-mode fracture. The use of finite element methods for calculating fracture criteria.
- A description of fatigue crack growth, Paris’ law, and finite element usage.
- Basic post-yield fracture mechanics, plasticity fundamentals, Irwin’s plastic zone size around crack tips, crack opening displacement, thickness effects, HRR fields, fracture criteria, and use of finite elements.
- A description of viscoelastic models.
- To describe the phenomenon of creep, including the different types of creep curves, constitutive laws, hardening effects.
- Causes and effects of impact damage on composite materials.
- Failure criteria for notched and impacted composite laminates.
- Failure of composite plies and its evaluation in different coordinate systems
- Failure of laminates and design methods to prevent failure.
- Interlaminar stresses and delamination growth in composite laminates.
- Bending and buckling of orthotropic plates and laminates.