Fracture Mechanics and Fatigue Design

Fatigue failure and fracture often occur in various branches of engineering being one of the main reasons of unexpected termination of anticipated service lives of mechanical components. This leads to unfortunate catastrophic structural failures resulting in loss of lives and in excessive costs. The theory behind fatigue and fracture mechanics enables the analysis of structural integrity of engineering components and helps preventing the occurrence of structural failure. Fatigue and fracture mechanics as a scientific discipline has enabled scientists and engineers to speak the same language when dealing with the design and manufacturing of mechanical components and structures.

This course deals with fundamental and technical issues associate with designing and maintaining structures that are subjected to static and cyclic mechanical loading. Students will be taught the principles of fatigue and fracture mechanics and methodologies to evaluate material’s resistance to these failures by mechanical testing, addressing the questions on how fatigue behavior is characterized, how failure due to fatigue and fracture is predicted, and ultimately how this behavior is linked to the microstructure of the material and also the design of the component. An introduction on key applications of fracture mechanics and fatigue design in industry including failure analysis, design against failure, fatigue life estimation and experimental procedures for damage detection will also be provided in the course.

Knowledge:

• Knowledge of basic fatigue and fracture mechanics theories and their physical failure mechanisms.
• Understanding of the application of fatigue and fracture mechanics to specific engineering problems.
• Detailed knowledge of experimental and FE-based numerical tools for evaluating the failure due to fatigue and fracture in materials and structures.
• Methodology for designing against fatigue.

Skills:

• Capability to use traditional and numerical methods for designing mechanical components against fatigue.
• Capability to use crack-growth analysis for load bearing and fatigue life assessment of mechanical components containing cracks, crack-like defects and geometrical complexities (also known as notch).

General competence:

To be able to evaluate fatigue damage and resistance against fracture and to design machines and structures against fatigue and fracture failure and to predict the expected life of components in service.

Lectures: Both presentations and Canvas are used in parallel for teaching. Some lectures can be performed "digitally". Teaching materials are provided through Canvas. The purchase of textbooks is not necessary for the successful completion of this course though it is encouraged for additional learning. Self-made notes during the lectures are encouraged since the lectures include the material and discussion which are hardly available in textbooks.

FE modelling training: The students are taught the basic knowledge and operation of FE analysis, as well as how to use ABAQUS as the selected FE program, as an effective tool to analyze fracture and fatigue life.