Course Contents - Introduction to Fatigue (fatigue as a phenomenon; stress concentrations; residual stresses; fatigue properties of metallic and
composite materials; fatigue strength of notched specimens, residual strength).
- Fatigue damage mechanisms (initiation, crack growth, delamination growth, transverse matrix cracking, fibre failure).
- Analysis methods (stress concentration factors, stress intensity factors; energy balance approaches, strain energy release rates).
- Fatigue loading (Load Spectra, Fatigue under Constant- & Variable-Amplitude Loading).
- Special Fatigue Conditions (surface treatments; fretting corrosion; corrosion fatigue; high-temperature and low-temperature
fatigue, moisture ingress).
- Fatigue and Damage Tolerance of Aircraft Structures: Regulations, tests, scatter, application of fatigue and damage tolerance
methods.
Study Goals This course provides the students with engineering knowledge and skills to recognize and to analyse fatigue and damage
tolerance problems in aircraft structures and materials.
After the course the student must be able
1. Interpret and discuss the fatigue fracture features with respect to the characteristics of each phase in fatigue life
2. Define and determine stress concentration factors for notched structures with or without residual stresses
3. Explain and discuss S-N curves with respect to mean stress, material surface effects, and scatter, and perform fatigue life
analyses considering mean stress and notch root plasticity
4. Assess the fatigue life of tension and shear joints, and explain limitations to the similarity principles (K,I,T)
5. Explain Linear Elastic Fracture Mechanics concepts for damage growth, and perform crack growth analyses with these
concepts
6. Explain the consequences of variable- and constant amplitude loading on fatigue life and damage growth, and perform fatigue
life analyses for arbitrary load spectra
7. Explain the effect of environment on fatigue life and fatigue phenomena
8. Perform residual strength analyses.
