Class Information

Course Description

Mechanisms of fracture and crack growth; stress analysis; crack tip plastic zone; energy principles in fracture mechanics; fatigue-crack initiation and propagation; fracture mechanic design and fatigue life prediction. Analytical, numerical, and experimental methods for determination of stress intensity factors. Current topics in fracture mechanics.

Syllabus

Class information

  • Hours: Mondays and Wednesdays 12:40-1:55 apm ET (11:40 am -12:55 pm CT)
  • Location: UTK:  Dougherty 406                    UTSI: Main Academic Building E110

Office Hours

Meetings are scheduled by sending emails to the instructor. [one_third last=”no”]Office: B209, Main academic building, UTSI[/one_third] [one_third last=”no”]Phone: (931) 393-7334[/one_third] [one_third last=”yes”][social_links colorscheme=”” linktarget=”_self” rss=”” facebook=”” twitter=”” dribbble=”” google=”” linkedin=”” blogger=”” tumblr=”” reddit=”” yahoo=”” deviantart=”” vimeo=”” youtube=”” pinterest=”” digg=”” flickr=”” forrst=”” myspace=”” skype=”skype:rpabedi?add”][/one_third]

 Course requirements

  • Homework 35% + 5% (extra credit)
  • Term project 20%: Use commercial software to evaluate stress intensity factor; Simple computations with cohesive and damage models.
  • Report and presentation on a topic on fracture 20%: 4-page report and 10-12 minute presentation at the end of the semester. Individual topics and references will be chosen by the instructor and the student.
  • Midterm and final exams 25%

Detail of course topics

Presentations

Announcements

  • HW1: link (Due 9/24/2018).
  • HW2: link (Due 10/10/2018).
  • Term project 1: Includes (About equal weights are allocated to each part)
    • 1) An up to 4 pages paper/proposal(including references if any) on a topic related to fracture mechanics. The format of the document is either that of a a) research article mostly focusing on introducing a topic of interest and presenting related results; b) research proposal that basically introduces a problem, discusses current state of the art and research gaps, and finally proposes a new approach to address the mentioned research gaps. The choice between research article or proposal is up to the student. The topic can be related to your own research work (as long as it is related to fracture mechanics) or any other topic related to the course that is of interest to you. I can help you in choosing a topic if needed. Please confirm your research topic by the end of 10/31/2018.
    • 2) Presentation of the article on the “Presentation day”. Each student will have about 15 minutes to present the material in the article (and related to it) to the entire class.
      • Presentation day: Date to be determined (during the final’s week); Location UTK (room 409 NOT 406); UTSI F110 (Those of you who cannot attend the presentation day should contact me, if not have already done, beforehand so I can arrange your presentations in one of our regular class hours).
  • Midterm exam: link (Due 10/24/2018).
  • Term Project 2 (Ansys Term project): Due 12/03/2018.
    • Ansys_FractureMechanics: Instructions for Ansys for computing stress intensity factor (K) and J integral.
    • UTSI accounts / Ansys commercial software:
    • Installing Ansys:
      • Option 1 (free academic version, link). While this is a limited version, it is sufficient for your project and is recommended due to the ease of installation.
      • Option 2 (UTSI): This option requires a UTSI username.
        • Setting up Ansys and connecting to UTSI network. This link summarizes the following steps.
        • VPN (link) must be installed to connect to UTSI network before launching Ansys
        • Ansys can be downloaded from here (Look for Anys 15.0). Run the file Install.bat from unzipped file to install Ansys. Note: Ansys only installed on Windows and linux systems. For more information contact the instructor.
        • Contact: helpdesk@utsi.edu (Contact the instructor first).
  • HW3: link (Due 11/26/2018).
  • Final exam: link (Due 12/10/2018).

Class timeline

RA: reading assignment; Reference made to section numbers in “details of course topics”

  1. 08/22/2018 Lecture: notes           2. History; 3.1 Fracture classification.
  2. 08/27/2018 Lecture: notes           3.2 & 3.3 Ductile and brittle fracture.
  3. 08/29/2018 Lecture: notes           4. Linear Elastic Fracture Mechanics (LEFM), 4.1.1. Atomic view of fracture.
  4. 09/05/2018 Lecture: notes           4.1.2. Effect of flaws, Griffith experiment; 4.1.3. Energy equation.
  5. 09/10/2018 Lecture: notes           4.1.3. Energy equation, Fracture Resistance (R); 4.1.4. Energy Release Rate (G).
  6. 09/12/2018 Lecture: notes            4.1.5. Crack Stability, R and ∏ curve; 4.2. Stress solutions, Stress Intensity Factor K (SIF): 4.2.1. Airy stress functions, 4.2.2. Complex variables and cylindrical coordinate.
  7. 09/17/2018 Lecture: notes            4.2.3. Stress solutions, stress concentration; 4.2.4. Crack tip stress fields, SIF.
  8. 09/19/2018 Lecture: notes            4.2.4. Crack tip displacement fields, SIF; Mixed mode fracture, evaluation of KI and KII.
  9. 09/24/2018 Lecture: notes            4.2.5. Relation between K & R (SIF & Resistance); 5.2. Plastic zone models.
  10. 09/26/2018 Lecture: notes            5.2. Plastic zone models: 5.2.1. 1D models: Irwin model.
  11. 10/01/2018 Lecture: notes           5.2 Plastic zone models 5.2.2.2D models.
  12. 10/03/2018 Lecture: notes           5.3. J Integral: 5.3.1. Path independence; 5.3.2.Relation between J and G.
    Link: Derivation of the relation J = G
  13. 10/08/2018 Lecture: notes           5.3.5.Plastic crack tip fields; Hutchinson, Rice and Rosengren (HRR); 5.3.4.Energy Release Rate.
  14. 10/10/2018 Lecture: notes           5.3.4.Energy Release Rate, crack growth and R curves; 5.3.6. large scale yielding (LSY) and 5.4. Crack tip opening displacement (CTOD).
  15. 10/15/2018 Lecture: notes           5.3.7.Fracture mechanics versus material (plastic) strength; 6.1. Fracture mechanics in Finite Element Methods (FEM).
  16. 10/17/2018 Lecture: notes           6. Computational fracture mechanics, 6.1.3. Extraction of K (SIF), G.
  17. 10/22/2018 Lecture: notes          6. Computational fracture mechanics, 6.1.4. J integral.
  18. 10/24/2018 Lecture: notes           Demo of computation of K in Ansys (from displacement method and J integral).
  19. 10/29/2018 Lecture: notes         6.1.6, 7 Computational crack growth, Extended Finite Element Method (XFEM); 6.2. TSRs (part1)
  20. 10/31/2018 Lecture: notes          6.2. TSRs (part 2)
  21. 11/05/2018 Lecture: notes          4.3. Mixed mode fracture
  22. 11/07/2018 Lecture: notes           4.3.2. Nucleation criteria; 8. Fatigue; 8.1. Fatigue regimes; 8.2. S-N curves.
  23. 11/12/2018 Lecture: notes           8.3. Paris law; 8.4. Variable and random load (part 1).
  24. 11/19/2018 Lecture: notes           8. Fatigue (remaining topics);  Dynamic Fracture (part 1).
  25. 11/26/2018 Lecture: notes           Dynamic Fracture (part 2): LEFM solutions for dynamic fracture; sample mode I problem.
  26. 11/28/2018 Lecture: notes           Dynamic Fracture (part 3): Rayleigh wave speed limit for mode I fracture; damage mechanics (part 1).
  27. 11/30/2018 Lecture: notes           Damage mechanics (part 2).

Selected Bibliography

  1. T. L. Anderson, Fracture Mechanics: Fundamentals and Applications, 3rd Edition, CRC Press, USA, 2004 (main textbook).
  2. D. Broek, Elementary Engineering Fracture Mechanics, 4th Revised Edition, Springer, 1982 (or reprint 2013).
  3. B. Broek, The Practical Use of Fracture Mechanics, Springer, 1998.
  4. S. Murakami, Continuum Damage Mechanics: A Continuum Mechanics Approach to the Analysis of Damage and Fracture, Springer Netherlands, Dordrecht, 2012.
  5. S. Suresh, Fatigue of Materials. 2nd ed. Cambridge University Press, 1998.
  6. L.B. Freund, Dynamic Fracture Mechanics, Cambridge University Press, 1998.
  7. B. Lawn, Fracture of Brittle Solids, Cambridge University Press, 1993.
  8. M.F. Kanninen and C.H. Popelar, Advanced Fracture Mechanics, Oxford Press, 1985.
  9. R.W. Hertzberg, Deformation and Fracture Mechanics of Engineering Materials. 5th ed. John Wiley & Sons, Inc., 2012 (material focus).
  10. S Al Laham, Stress Intensity Factor and Limit Load Handbook, British Energy Generation Limited, 1998.
  11. H Tada, P.C. Paris, G.R. Irwin, Stress Analysis of Cracks Handbook,  3rd ed., ASME Press. 2000

Useful online courseware and links

  1. Presentation on Fracture Mechanics by Dr. N. V. Phu from University of Adelaide. With special thanks to Dr. Phu, the majority of course presentations are based on Dr. Phu’s presentations.
  2. S. Suresh, Fracture and Fatigue, MITOpen courseware.
  3. V.E. Saouma, Fracture Mechanics lecture notes, University of Colorado, Boulder.
  4. P.J.G. Schreurs, Fracture Mechanics lecture notes, Eindhoven University of Technology (2012).
  5. A.T. Zender, Fracture Mechanics lecture notes, Cornell University.
  6. K. Ramesh, Engineering fracture mechanics lecture videos, IIT, Madras, India.
  7. L. Zhigilei, MSE 2090: Introduction to the Science and Engineering of Materials, University of Virginia: Excellent lecture notes on material preliminaries such as atomic structure (ch2), crystalline solids (ch3), imperfections (ch4), mechanical properties (ch6), dislocation (ch7), and failure (ch8).