Course detail
Dislocations and Plastic Deformation
FSI-WDD Acad. year: 2022/2023 Summer semester
Basic mechanisms of plastic deformation in metallic crystals, specific features of plastic deformation in macromolecular substances. A physics view of ceramic plasticity. Dislocation substructure of metallic and non-metallic crystals. Mechanisms of the interaction between dislocations and structural components (grain boundaries, subgrain boundaries, point defects, precipitates, etc.). Interaction between dislocations. Hardening and dehardening processes.
Language of instruction
Czech
Number of ECTS credits
5
Supervisor
Learning outcomes of the course unit
The knowledge of the processes of plastic deformation in crystals. Relation between sub-microscopic events in solids and macroscopic manifestation of these events – i.e. changes in mechanical properties.
Prerequisites
Atomic bonds, fundamentals of crystallography, crystallographic systems, crystal symmetry, crystal lattice defects, crystalline structure of solid solutions and intermediate phases in metallic and ceramic systems.
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
Course-unit credit: Awarding the credit is conditional on attendance at all exercises and on written reports on the tasks assigned. Examination: In the written part, students answer four questions. Three questions are theoretical, one is practical. In this part of the exam, students may use available literature, with the exception of the course book. In the oral part, students explain the theoretical topics as prompted by the examiner.
Aims
The course concentrates on explaining the essence of the formation of mechanical properties of metallic and non-metallic substances, in dependence on faulted crystal lattice. Information is provided about the mechanisms of plastic deformation in single-crystal and polycrystalline materials, deformation textures, and strain hardening. In the exercises, students learn the experimental methods for studying plastic deformation.
Specification of controlled education, way of implementation and compensation for absences
Attendance at exercises is compulsory. Absence from exercises must be accounted for. Students who have missed an exercise will be given an extra assignment. They will prove in the form of a written report that they have mastered the given topic.
The study programmes with the given course
Programme N-MTI-P: Materials Engineering, Master's, compulsory
Type of course unit
Lecture
26 hours, optionally
Teacher / Lecturer
Syllabus
1. Crystallography of plastic deformation
2. Theory of critical slip stress
3. Process of strain hardening
4. Plastic deformation of non-metallic crystals
5. Dislocations
6. Slip plane, conservative and non-conservative motion of dislocations
7. Distribution of dislocations
8. Interaction between dislocations
9. Dislocations and grain boundaries (the Haal-Petch relation)
10. Dislocation sources
11. Partial dislocations
12. Stacking faults and their significance
13. Dislocations and allotropic transformation
14. Concluding the course and summarizing the most significant items of knowledge
Laboratory exercise
26 hours, compulsory
Teacher / Lecturer
Syllabus
1. Stereographic projection, orientation of crystals. 2. Reciprocal lattice (definition, application). 3. Radiographic methods of studying crystal orientation. 4. Methods for studying textures, pole figures. 5. Electron diffractography. 6. Methods for establishing dislocation density. 7. Metallography of dislocation substructure.