Directly solidified eutectics

The elastic moduli vs. temperature curves of the hypoeutectic Ti-Si7.5-All alloy and of the directionally solidified eutectic a-Ti-Ti5Si3 composite with discontinuous Ti5Si3 fibers -aspect ratio of lf/df 50- are depicted in fig. 14. In comparison the temperature-dependent Young s modulus of the polycrystalline Ti5Si3 compound is also shown in the diagram. A detailed description and discussion of the elastic moduli of the pure silicides is given in section 4.3. 

FIGURE 3-21 One-hour bend stress relaxation ratio for directionally solidified eutectic YAG/alumina fibers grown by edge-defined film growth (EFG), for polycrystalline alumina-based fibers, and for c-axis sapphire fibers. Source Morscher et al., 1995. 

A particular type of fibre-reinforced composite is the directionally solidified eutectics in which matrix and reinforcement are made in one single process from one or two different materials. The reinforcement usually has the form of plates or rods and their orientation may be designed and controlled in the solidification process. Only the volume fraction of the reinforcement cannot be designed arbitrarily and is determined by the applied technological processes. 

Charles C. Sorrell, Vladimir S. Stubican, Richard C. Bradt. Mechanical Properties of ZrC-ZrB2 and ZrC-TiB2 Directionally Solidified Eutectics. Journal of the American Ceramic Society 1986 69 3I7. 

Bogomol, I., Nishimura, T., Nesterenko, Yu., Vasylkiv, O., Sakka, Y, Loboda, P. (2011). The Bending Strength Temperature Dependence of the Directionally Solidified Eutectic LaBg-ZrB2 Composite. Journal of Alloys and Compounds, 509(20), 6123-6129. doi 10.1016/j.jallcom.2011.02.176. 

Llorca, J., Orera, V. M. (2006). Directionally solidified eutectic ceramic oxides. Progress in Materials Science, 51,711-809. doi 10.1016/j.pmatsci.2005.10.002. 

Perriere, L., Valle, R., Mazerolles, L., Parlier, M. (2008). Crack propagation in directionally solidified eutectic ceramics. Journal of the European Ceramic Society, 28, 2337-2343. doi 10.1016/j.jeurceramsoc.2008.01.005. 

Ramirez-Rico, J., Pinto-Gomez, A. R., Martinez-Fernandez, J., de Arellano-Lopez, A. R., Oliete, P. B., Pena, J. I., Orera, V. M. (2006). High-temperature plastic behaviour of Al Oj-YjAl Oj directionally solidified eutectics. ActaMaterialia, 54, 3107-3116. doi 10.1016/j.actamat.2006.03.002. 

Torii, S., Kamiyama, T., Oikawa, K., Waku, Y, Fukunaga, T. (2005). Strain measurement of the directionally solidified eutectic Al Oj/YjAljOj (YAG) ceramic by neutron diffraction. Journal erf the European Ceramic Society, 25, 1307-1311. doi 10.1016/j. jeurceramsoc.2005.01.026. 

Rev] Reviere, R., Sauthoff, G., Johnson, D.R., Oliver, B.F., Microstracture of Directionally Solidified Eutectic Based Fe(Al,Ta)/Fe2Ta(Al) Alloys as a Function of Processing Conditions , IntermetalUcs, 5(3), 161-172 (1997) (Experimental, Morphology, Phase Diagram, Phase Relations, 10)... 

Sorrell, C.C., Stubican, V.S. and Bradt, R.C., Mechanical Properties of ZrC-ZrBp and ZrC-TiBp Directionally Solidified Eutectics. J. Amer. Ceram. Soc. 69 [4] 317-32111986). 

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