Synthesis of an Al{sub 2}O{sub 3}/Al co-continuous composite by reactive melt infiltration
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China)
The route for the fabrication of an Al{sub 2}O{sub 3}/Al co-continuous composite by reactive melt infiltration was investigated using scanning electron microscopy, energy dispersive X-ray microanalysis and X-ray diffraction analysis. It was found that in the process of molten aluminium infiltration into the SiO{sub 2} preform, the chemical reaction of 3SiO{sub 2} + 4Al {sup {yields}} 2Al{sub 2}O{sub 3} + 3Si occurred at the infiltration front, and generated a transition zone containing a new type of continuous porosity about 100 {mu}m in width. The reaction continued with further infiltration of molten aluminium alloy into this porosity which reacted with the residual SiO{sub 2} until all the SiO{sub 2} was transformed into Al{sub 2}O{sub 3}. A comparison was made between this route and that by direct infiltration of molten aluminium alloy into the open porosity of an Al{sub 2}O{sub 3} preform. As a result of the increased wetting ability of the molten aluminium alloy by the chemical reaction, reactive melt infiltration took place at a higher rate for the SiO{sub 2} preform than that for the direct infiltration of the Al{sub 2}O{sub 3} preform. A fracture surface examination demonstrated a toughening effect provided by the continuous aluminium alloy in the composite.
- OSTI ID:
- 21003553
- Journal Information:
- Materials Characterization, Vol. 58, Issue 5; Other Information: DOI: 10.1016/j.matchar.2006.06.006; PII: S1044-5803(06)00200-2; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
- Country of Publication:
- United States
- Language:
- English
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