Having attended a basic course on Materials Science and Engineering (suggested)

If not done before, attending a basic course on Materials Science and Engineering during the course of Mechanical Behaviour of Materials (suggested).

This course enables the course of Composite Materials Science and Engineering (2nd year) (suggested).

The teaching is based upon lectures, exercises and team work. The students work in teams on three cases, and 40% of the final grade is based on the achievements from these cases. Laboratory exercises are included in the cases. The first case is introduced the first week of the semester, and the students are kindly asked to show up the first week. Assessment for the course is partially based on group projects. If significant differences in the contributions from group members have been documented, individual adjustment of final grading may be considered. If there is a re-sit examination, the examination form may be changed from written to oral.

1. Introduction to deformation behaviour: Concept of stresses and strains, engineering stresses and strains, Different types of loading and temperature encountered in applications.

2. Tensile Test - stress-strain response for metal, ceramic and polymer, elastic region, yield point, plastic deformation, necking and fracture.

3. Bonding and Material Behaviour, theoretical estimates of yield strength in metals and ceramics.

4. Elasticity (the State of Stress and strain, stress and strain tensor, tensor transformation, principal stress and strain, elastic stress-strain relation, anisotropy, elastic behaviour of metals, ceramics and polymers).

5. Viscoelasticity (Molecular foundations of polymer viscoelasticity. Rouse-Bueche theory, Boltzmann superposition principle, mechanical models, distribution of relaxation and retardation times, interrelationships between mechanical spectra, the glass transition, secondary relaxations, dielectric relaxations.

6. Plasticity (Hydrostatic and Deviatoric stress, Octahedral stress, yield criteria and yield surface, texture and distortion of yield surface, Limitation of engineering strain at large deformation, true stress and true strain, effective stress, effective strain, flow rules, strain hardening, Ramberg-Osgood equation, stress -strain relation in plasticity, plastic deformation of metals and polymers).

7. Microscopic view of plastic deformation: crystals and defects, classification of defects, thermodynamics of defects, geometry of dislocations, slip and glide, dislocation generation - Frank Read and grain boundary sources, stress and strain field around dislocations, force on dislocation - self-stress, dislocation interactions, partial dislocations, twinning, dislocation movement and strain rate, deformation behavior of single crystal, critical resolved shear stress (CRSS), deformation of poly-crystals, Hall-Petch and other hardening mechanisms, grain size effect - source limited plasticity, Hall-Petch breakdown, dislocations in ceramics and glasses. Effects of microstructure on the mechanics of polymeric media: deformation modes, yield, rubber toughening, alloys and blends.

8. Fracture mechanics (energetics of fracture growth, plasticity at the fracture tip, measurement of fracture toughness, - Linear fracture mechanics -KIC.  Elasto-plastic fracture mechanics - JIC, Measurement and ASTM standards, Design based on fracture mechanics, effect of environment, effect of microstructure on KIC and JIC. Application of fracture mechanics in the design of metals, ceramics, polymers and composites, damage tolerance design, elements of fractography)

9. Fatigue (S-N curves, low- and high-cycle fatigue, laboratory testing in fatigue, residual stress, surface and environmental effects, fatigue of cracked components, designing out fatigue failure, Life cycle prediction, Fatigue in metals, ceramics, polymers and composites.

10. Creep. Creep in crystalline materials (stress-strain-time relationship, creep testing, different stages of creep, creep mechanisms and creep mechanism maps, diffusion, creep and stress rupture, creep under multi-axial loading, microstructural aspects of creep and design of creep resistant alloys, high temperature deformation of ceramics and polymers.

Hertzberg, R. W. Deformation and Fracture Mechanics for Engineering Materials. New York, NY: John Wiley & Sons Inc., 1995. ISBN: 9780471012146.

Meyers, M.A., Chawla, K.K. Mechanical Behavior of Materials 2nd Edition, Cambridge UK: Cambridge University Press, 2008. ISBN: 9780521866750.

Courtney, T.H. Mechanical Behavior of Materials. 2nd ed. Long Grove, IL: Waveland Press Inc., 2005. ISBN: 9781577664253.

Dowling, N.E. Mechanical Behavior of Materials. Englewood Cliffs, NJ: Prentice Hall, 1993. ISBN: 9780135790465.

Hosford, W.M. Mechanical Behavior of Materials. 2nd ed. Cambridge, UK: Cambridge University Press, 2010. ISBN: 9780521195690.

Dieter, G. E. Mechanical Metallurgy. New York, NY: McGraw-Hill, 1986. ISBN: 9780070168930.

• Notes taken in class
• Slides given from the teacher after each class, and available on the elearning platform.

Contact the teacher for the didactical material and course information.

http://matnano.ing.unipi.it/en/

This course introduces basic concepts and principles behind material deformation, fracture, fatigue and creep. Macro-mechanical properties and microscopic analysis will be correlated whenever possible to provide insights into materials fundamentals behind the observed behaviors. The ultimate goal is to enable students to apply these principles in materials design & selection under various mechanical conditions.