Course detail

Fractography

FSI-WFR Acad. year: 2020/2021 Winter semester

Failure causes and effects. Methods of fractographic analysis. Systematization of the concepts. Fracture micromechanisms. Cleavage and ductile fractures. Quasi-cleavage. Fatigue fractures. Creep fractures. Specific types of fracture. Examples of fractures occurring in operation, and procedures used in their examination.

Language of instruction

Czech

Number of ECTS credits

3

Learning outcomes of the course unit

The knowledge of failure micromechanisms and methods of studying them. Understanding the relations between the properties of materials, the causes of their failures, and ways of preventing failures. The application of fractography as an important tool in solving production problems and breakdowns.

Prerequisites

The basic knowledge in the field of materials engineering, with emphasis on the relations between the real structure and performance of materials. In-depth knowledge of limit states, in particular the problems of testing mechanical properties and failure mechanisms. The knowledge of the following experimental methods is also assumed: metallography, scanning electron microscopy, X-ray spectral microanalysis (EDS and WDS), Auger spectroscopy.

Planned learning activities and teaching methods

The course is taught through lectures explaining the basic principles and theory of the discipline. Teaching is suplemented by practical laboratory work.

Assesment methods and criteria linked to learning outcomes

Graded course-unit credit in the form of presenting an assigned or chosen problem before the group of fellow-students.

Aims

The course focuses on the explanation of the causes of machine-part failures, failure micromechanisms, methods of macrofractographic and microfractographic studies, classification and description of fracture appearance with the aim of making students familiar with the potentials of applying fractography to the solution of practical production problems, breakdowns and their causes, optimisation of materials selection, etc.

Specification of controlled education, way of implementation and compensation for absences

Compulsory attendance at exercises. Absence from exercises is dealt with by assigning a topic for a written presentation (usually selected papers from literature).

The study programmes with the given course

Type of course unit

 

Lecture

26 hours, optionally

Teacher / Lecturer

Syllabus

1. Fracture causes and results.
2. Methods of fractographic analysis.
3. Methods of fractographic analysis.
4. Systematisation of fractographic concepts and failure micromechanisms.
5. Systematisation of fractographic concepts and failure micromechanisms.
6. Transcrystalline fractures.
7. Intercrystalline fractures.
8. Fatigue fractures.
9. Creep fractures.
10. Corrosion under stress.
11. Special cases of fractures.
12. Special cases of fractures.
13. Methodology for solving the causes of fractures during operation.

Laboratory exercise

13 hours, compulsory

Teacher / Lecturer

Syllabus

1. Preparation of fracture surfaces for examination by REM and TEM.
2. TEM – Analysing the replicas from preceding exercises.
3-4. Illustration of fracture surfaces on REM.
5. Writing a test on failure micromechanisms.
6. Examples of fractures occurring during operation, and their examination.
7. Course-unit credit.