Fracture Mechanics 1

Garant předmětu:

Lecturer:

Tutor:

Supervisor:

Department of Materials

Synopsis:

Mechanisms and modes of fracture. Stress and strain field in the vicinity of notch or crack tip. Parameters of linear elastic fracture mechanics. Total energy balance approach. Fracture toughness of materials and crack stability examination. Application in research and engineering practice.

Requirements:

Engineering Mechanics.

Theory of Elasticity.

Syllabus of lectures:

1.Fracture modes and crack growth mechanisms

2.Stress and strain field around notches and cracks - theoretical background

3.Loading of cracked body - opening, sliding, and tearing modes, criterion of crack stability

4.Stress intensity factor - definition, calculation, influence of finite dimensions of body, boundary conditions, etc., fracture toughness - significance in practice, standard testing methods

5.Crack tip plastic zone under plane stress and plane strain conditions - analytical calculation and experimental determination of size and shape

6.Total energy balance approach - energy release rate, Griffith's criterion, R-curves

7.Sih's strain energy density factor - mixed mode problem, prediction of crack growth direction

8.Relations between parameters of linear elastic fracture mechanics

9.Examples and case studies

Syllabus of tutorials:

Calculation of stress intensity factor, fracture toughness and crack tip plastic zone size. Determination of ct¨ritical crack length or critical stress. Calculation of crack growth direction in the case of mixed mode.

Study Objective:

Knowledge: To obtain basic theoretical knowledges from linear fracture mechanics.

Skills: Ability to solve simple practical problems dealing with the bodies with cracks in elastic stress state.

Study materials:

Key references:

[1] Kunz, J.: Applied Fracture Mechanics. Praha, Vydavatelství ČVUT 2005 (in Czech).

Recommended references:

[1] Anderson, T.L.: Fracture mechanics. Fundamentals and Applications. Boca Raton and New York, CRC Press 1995.

Media and Tools:

Murakami, Y. et al.: Stress Intensity Factors Handbook. Oxford, Pergamon Press 1987.

Calculator or Notebook.

Note:

Further information:

No time-table has been prepared for this course

The course is a part of the following study plans: