ME583 ENGINEERING FRACTURE MECHANICS
| Course Code: | 5690583 |
| METU Credit (Theoretical-Laboratory hours/week): | 3 (3.00 - 0.00) |
| ECTS Credit: | 8.0 |
| Department: | Mechanical Engineering |
| Language of Instruction: | English |
| Level of Study: | Graduate |
| Course Coordinator: | Prof.Dr. SERKAN DAĞ |
| Offered Semester: | Fall and Spring Semesters. |
Course Objectives
At the end of this course, the students will be equipped to comprehend
1. fundamentals of linear elastic fracture mechanics including the concepts of Westegaard stress function, asymptotic fields, stress intensity factor, mode-mixity, 3D crack tip fields, and fracture criteria
2. the concepts of small scale yielding, crack-tip plastic zone, fracture toughness, and micromechanical modes of fracture
3. Griffith theory, and definitions involving energy release rate, crack stability, and R-curves
4. plane strain fracture toughness and R-curve measurement methods
5. concepts involving fatigue crack propagation, Paris-Erdoğan equation, propagation of a semi-elliptical surface crack, variable amplitude loading, and Wheeler’s model
6. elastic-plastic fracture concepts such as J-integral, HRR fields, and J-estimation methods
Course Content
Basic concepts: Failure criteria, mechanisms of fracture, stress intensity factor. Energy balance and stress intensity factor approaches to fracture. Plane strain and plane stress fracture toughness of materials. Fatigue crack growth. Elastic-plastic fracture, plastic zone models, J-integral. Fail-safe and safe-life design concepts, damage tolerances. Applications to practical problems. (F)
Course Learning Outcomes
1. Ability to develop the stress function based formulation in plane elasticity
2. Ability to utilize complex Westergaard stress functions in the solution of crack problems
3. Ability to derive stresses, asymptotic fields and stress intensity factors for fundamental crack problems via Westergaard approach
4. Ability to calculate SIFs for different types of crack problems
5. Ability to calculate the SIF for the semi-elliptical surface crack
6. Ability to perform failure analysis by implementing mode I and mixed-mode fracture criteria
7. Ability to calculate and intepret crack-tip plastic zone size for plane stress and strain
8. Ability to generate approximate crack-tip stress distribution in accordance with Irwin’s model
9. Ability to calculate energy release rate for various fracture specimens considering displacement- and force control
10. Ability to perform R-curve-based stability analysis
11. Ability to carry out fracture tests following available standards for plane strain fracture toughness and R-curve
12. Ability to conduct fatigue crack propagation analysis in 2D and 3D utilizing Paris-Erdoğan equation
13. Ability to conduct fatigue crack propagation analysis for variable amplitude loading utilizing Wheeler’s model
14. Ability to calculate J-integral for materials displaying linear elasticity and deformation theory of plasticity
Program Outcomes Matrix
| Contribution | |||||
| # | Program Outcomes | No | Yes | ||
| 1 | Acquires the fundamental scientific knowledge required to analyze and solve advanced-level problems in the field of mechanical engineering. | ✔ | |||
| 2 | Gains the competence to utilize advanced engineering mathematics methods in the formulation, analysis, and solution of engineering problems. | ✔ | |||
| 3 | Conducts literature reviews using printed and online sources, analyzes the collected literature, and identifies the current state-of-the-art in the relevant scientific field. | ✔ | |||
| 4 | Demonstrates the ability to prepare and deliver a seminar on a technical subject. | ✔ | |||
| 5 | Develops the ability to conduct independent research on a specific topic and solve advanced engineering problems. | ✔ | |||
| 6 | Contributes to the national and/or international body of knowledge through original research. | ✔ | |||
| 7 | Gains the competence to effectively communicate the process and results of research conducted on a specific subject through scientifically structured written reports and oral presentations. | ✔ | |||
| 8 | Acquires the ability to publish research findings as articles in national and/or international scientific journals and/or present them as papers at conferences. | ✔ | |||
| 9 | Acts in accordance with universal principles of research and publication ethics. | ✔ | |||