| Code |
18167
|
| Year |
2
|
| Semester |
S1
|
| ECTS Credits |
6
|
| Workload |
TP(60H)
|
| Scientific area |
Engenharia Mecânica
|
|
Entry requirements |
N.A.
|
|
Learning outcomes |
This course aims to provide a deep understanding of the fundamentals of fracture mechanics, both for ductile and brittle materials, and the techniques used to analyze the behavior of materials when subjected to critical loads that can lead to structural failures. By the end of the course, students should be able to:
-Understand the historical evolution of fracture mechanics and its impact on engineering design.
- Apply fundamental concepts of fracture mechanics in the design of structural components subjected to cyclic loading.
-Analyze the influence of different types of stresses (mean and variable) on fatigue behavior and the effects of stress concentration at the crack tip.
- Use cycle counting methods to evaluate the life cycle of components subjected to multiaxial fatigue.
- Apply damage tolerance tools and structural safety concepts in engineering practices.
|
|
Syllabus |
1 – Introduction to Fracture Mechanics: Historical perspective; Fracture-focused design approach and damage tolerance.
2 – S-N Fatigue Approach: Definitions; S-N curve; Influence of mean and variable stress; Multiaxial fatigue; Palmgren-Miner rule; Cycle counting models; Stress concentration effects at the crack tip.
3 – Linear Elastic Fracture Mechanics: Definitions; Griffith's energy balance; Energy release rate; Instability and R-curve; Stress analysis at crack tips; Crack tip plasticity; Fracture controlled by the K-intensity factor.
4 – Fatigue Crack Growth: Definitions; Description of fatigue crack growth; Fatigue crack growth rate; Fatigue crack growth equations (Paris, Walker, Forman, Collipriest); Life estimation for constant amplitude loading; Life estimation for variable amplitude loading; Sequence effects.
|
|
Main Bibliography |
Anderson, T. L. (2017) “Fracture Mechanics – Fundamentals and Applications (4th edition)”
Dowling, N.E. (2013) “Mechanical Behavior of Materials: Engineering Methods for Deformation, Fracture, and Fatigue”
Broek, D (1982) “Elementary engineering fracture mechanics”
Knott, J., (1973) “Fundamental of Fracture Mechanics”
|
|
Teaching Methodologies and Assessment Criteria |
Evaluation is continuous and carried out in two stages: (i) a written test (TE); and (ii) a set of assignments (TP), evaluating different aspects of the competencies acquired by the students. The learning process classification is NFA=0.3xTE+0.7xTP. Approval occurs when, cumulatively, NFA>=10, TE>=8, and TP>=6. The condition for exam access is TE>=8 and TP>=6. The exam evaluation is based on a
written test (NE) and the assignments carried out during the semester (the assignments are only done once). The exam classification is NFE=0.3xNE+0.7xTP.
|
|
Language |
Portuguese. Tutorial support is available in English.
|