Co-investigator: doc. Ing. Ivo Dlouhý, CSc.
Number of Project: GA106/06/0646
Agency: Czech Science Foundation
Duration: 01. 01. 2006 - 31. 12. 2008

Micro-structural effects on the fractality of cracks in brittle and quasi-brittle materials will be investigated. Irregularities of fracture surface described by self-similar or self-affine fractals will be followed in the direct relationship tomicro-mechanisms of fracture initiation and propagation and as a function of local energy release rate and crack velocity. Since the fracture surfaces correspond to conditions of self-affinity in almost all cases, new transformation of such surfaceco-ordinates will be found so that surface roughness image is scale invariant. The principal aim of the project is to formulate a fractal model for prediction of fracture damage development from its initiation to final brittle fracture instability. Themodel will be experimentally verified on selected ceramics, steels and other quasi-brittle materials. Fractal modelling of fracture surface creation in brittle materials could reveal new geometrical sources of toughening. Using an experimental data and

Řehořek, L., Dlouhý, I.: Quantification of fracture surfaces using confocal laser microscopy and selected quantitative parameters, 2008, IC London, seminar lecture –nepublik. přednáška.

Dlouhý, I., Hadraba, H., Jurášek, L.: Local approach use at solution of fracture parameters transferability; New Methods of Damage and Failure Analysis of Structural Parts, Ostrava, 2006, pp. 195-205.

Kotrechko, S., Strnadel, B., Dlouhý, I.: Fracture toughness of cast ferritic steel applying local approach, Theoretical and applied fracture mechanics, Vol. 47, Issue 2 , April 2007, pp 171-181.

Šmída, T., Babjak, J., Dlouhý, I.: Predikce referenční teploty z parametrů tahových zkoušek; Porušování a design materiálu, In Porušování a design materiálů, Sborník semináře Křehký lom 2007, ISBN 978-80-254-0725-7, Dlouhý Ivo, Brno, ÚFM AVČR, 2007, 33-46

Dlouhý, I., Strnadel, B.: The effect of crack propagation mechanism on the fractal dimension of fracture surfaces in steel; Engineering Fracture Mechanics 75, 2008, 3-4, 726-738

Kotrechko, S., Strnadel, B., Dlouhý, I.: Fracture toughness of cast ferritic steel applying local approach; Annual Proceeding of Science and Technology at VŠB-TUO, ISBN 978-80-248-1662-3, Ostrava, 2007, 62-67.

Strnadel, B., Dlouhý, I.: Fractalanisotropy and Heterogeneity of Fracture Surfaces in Steel; New Methods of Damage and Failure Analysis of Structural Parts, Ostrava, 2008, pp. 365-372.

Dlouhý, I.: Lomová houževnatost křehkých materiálů; teze přednášky k profesorskému jmenovacímu řízení v oboru materiálové inženýrství, Brno, 2008, str. 1-26.

I. Dlouhý, H. Hadraba, T. Šmída, J. Babjak: Predikce teplotní závislosti lomové houževnatosti z parametrů tahových zkoušek (Prediction of Fracture Toughness Temperature Diagram from Tensile Test Parmaeters); 22nd International conference on Heat Treatment, Brno, 2008, s. 11-20.

Hadraba, H., Dlouhý, I.: Fracture Behaviour of RAFM stee Eurofer´97 after Thermal Ageing; New Methods of Damage and Failure Analysis of Structural Parts, Ostrava, 2008, pp. 225-233.

Hadraba, H., Dlouhý, I.: Fracture Behavior of EUROFER´97 Steel After Thermal Ageing; 17th Eutopean conference on Fracture, Brno, 2008, pp. 1389-1396.