Přehled

This work aims to design and describe suitable methods of shrinkage compensation and/or control for the preparation of matrix composites and their effect on microstructural changes and fracture behaviour of hybrid composite materials containing such adapted matrix and ceramic fibres.

The main goal of the doctoral thesis will be the design and characterization of hybrid composites using, for example, fillers to suppress and/or control matrix shrinkage during partial pyrolysis. The work will consist of analyses of microstructural changes of hybrid materials based on polysiloxane resins, optimization of the preparation of composites and their characterization. Furthermore, from the determination of the influence of the method of compensation of shrinkage during pyrolysis on the resulting properties of the matrix. The use of matrix precursors thus prepared for the preparation of fibre-reinforced composites will also be studied. The influence of shrinkage compensation on the micromechanisms of failure and other properties of the prepared hybrid composite materials will be also studied. Due to the complicated microstructure and the number of present interfaces, it will be necessary to develop a procedure to obtain local properties describing the interfaces for numerical simulations. Simulations will result in the prediction of stress distribution formed during the material preparation. Within the work, it will be necessary to elaborate the issues related to the influence of the surrounding matrix by the presence of e.g. fillers, i.e. local changes in the microstructure, stress state and the like, and the impact of these changes on global characteristics. The involvement of advanced techniques of electron microscopy, atomic force microscopy, acoustic emission, nanoindentation, etc. will be necessary to achieve the set goals.

https://www.ipm.cz/

Základní literární prameny / Basic literature:

  1. Chavla K.K., Ceramic Matrix Composite
  2. Anderson T.L., Fracture Mechanics: Fundamentals and Applications
  3. Černý M., Chlup Z., Strachota A., Halasová M., Rýglová Š., Schweigstillová J., Svítilová J., Havelcová M.: Changes in structure and in mechanical properties during the pyrolysis conversion of crosslinked polymethylsiloxane and polymethylphenylsiloxane resins to silicon oxycarbide glass. Ceram. Int. 41 (2015) 6237-6247
  4. Chlup Z., Černý M., Kácha P., Hadraba H., Strachota A.: Fracture resistance of partially pyrolysed polysiloxane preceramic polymer matrix composites reinforced by unidirectional basalt fibres. J. Eur. Ceram. Soc. 40 (2020) 4879-4885
  5. Chlup Z., Černý M., Strachota A., Rýglová Š., Schweigstillová J., Svítilová J., Trško L., Hadzima B.: Effect of Pyrolysis Temperature on the Behaviour of Environmentally Friendly Hybrid Basalt Fibre Reinforced Composites. Appl. Composite Mater. 29 (2022) 829-843