Microstructure and Mechanical Properties of Mullite Composites via Pressure Molding and by Oxidation of an Al-Si Alloy Powder

Abstract:

A novel technique to synthesize mullite by the oxidation of Al-Si alloy powder was used for the manufacture of mullite via pressure molding. The mixed powder was consisted of powders of Al-Si alloy, Al2O3 and SiO2 and additives or powders of Al-Si alloy, Al2O3, SiO2 and ZrO2 and additives. Those mixed powders were milled in nonaqueous slurry in order to prevent the oxidation of Al-Si alloy. Then the green bodies were pressureless sintered in air at ≥1380 °C. The Oxidation caused an internal volume expansion, resulting in reducing shrinkage stresses during reaction- bonding of composites, which minimized the sensitivity to crack formation. Comparing with non zirconia reinforced mullite composites, the effect of the microstructure and mechanical properties of mullite composites were studied.

• Periodical: Key Engineering Materials (Volumes 368-372)
• Pages: 815-817
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.368-372.815
• Online since: February 2008
• Authors: Shun Li, Jia Chen Liu, Zhong Qiu Li, Wei Fan, Peng Yu Zhang
• Keywords: Aluminium Silicon Alloy, Mullite Composite, Reaction Bonding, Zirconia

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