摘要
To build the relationship between solidification conditions and the interfacial bond strength,Al2O3f/Al-15Si composite solidified at different cooling rates were investigated by microstructure observation and mechanical testing.The results show that the interfacial bond strength of the as-cast composite is significantly enhanced after furnace-or air-cooling processes owning to the preferential nucleation and growth of the eutectic silicon on the fiber surface.The discontinuously distributed eutectic silicon on the fiber surface makes the fiber become coarse,resulting in the enhanced mechanical bond strength between fiber and matrix.However,the interfacial bond strength of the oil-cooled composite is not improved,showing that the silicon on the fiber surface is important for the improvement of the interfacial bond strength.The air-and furnace-cooled composites also have a higher tensile strength.
To build the relationship between solidification conditions and the interfacial bond strength,Al2O3f/Al-15Si composite solidified at different cooling rates were investigated by microstructure observation and mechanical testing.The results show that the interfacial bond strength of the as-cast composite is significantly enhanced after furnace-or air-cooling processes owning to the preferential nucleation and growth of the eutectic silicon on the fiber surface.The discontinuously distributed eutectic silicon on the fiber surface makes the fiber become coarse,resulting in the enhanced mechanical bond strength between fiber and matrix.However,the interfacial bond strength of the oil-cooled composite is not improved,showing that the silicon on the fiber surface is important for the improvement of the interfacial bond strength.The air-and furnace-cooled composites also have a higher tensile strength.
基金
This work is financially supported by the National Basic Research Program of China (No2006CB605203-3)
