Stress, Damage and Failure Mechanisms
Fatigue, stress corrosion, creep and brittle fracture are some of the ways materials fail. To live safely with damage in structures from aircraft to power stations, we need accurate and reliable predictive models to plan inspection, repair and retirement from service.
These models depend on understanding the failure and damage mechanisms and the driving forces for damage, such as stress. For example, the microstructure may change during lifetime with thermal aging or neutron irradiation. Stress may be from externally applied forces, such as pressure, or residual stresses from welding or fabrication. Uncertainty in models may cause over-conservative structural integrity assessments and unnecessarily large safety margins. This can lead to too-frequent inspection or early retirement, with very significant economical consequences for society.
Our research spans theoretical models of damage nucleation to engineering structural integrity assessment codes, using advanced materials characterisation and stress measurement techniques. Multi-scale modelling is applied from the level of irradiation-assisted segregation of alloying elements up to the effects of plastic constraint in large ductile structures. Much of our work is associated with the Materials Performance Centre.
Research interests
- Measurement and modelling of residual stress and damage interactions
- In-situ high resolution tomography of failure mechanisms
- Irradiation damage and sensitisation
- Stress corrosion cracking (SCC)
- Nucleation and propagation of short cracks (fatigue and SCC)
- 3D modelling of crack behaviour