The effects of addition of La on the microstructure of as-cast ADC12 A1-Alloy were investigated by using optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscope （SEM）, and energy disperse ...The effects of addition of La on the microstructure of as-cast ADC12 A1-Alloy were investigated by using optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscope （SEM）, and energy disperse spectroscopy （EDS）. The experimental results showed that the a-A1 and eutectic Si crystals were modified with the addition of 0.3 wt% La. The eutectic Si crystals showed a granular distribution. At the same time, the alloy possessed the best mechanical property. When more than 0.3 wt% La was added to ADC12 aluminum alloy, the microstructure of as-cast alloy was coarsening gradually with the increase of the content of La and the mechanical property decreased. The effect of rare earth La which was added in ADC 12 A1-Alloy for up to 0.9 wt% had been investigated in this study. The dendrites ofADC12 Al-alloy was refined obviously and the morphology of Si crystals showed a particle structure when the addition of La reached 0,3 wt%. Besides, the acicular La-rich intermetallics in the alloy deteriorated the mechanical property of alloy： To avoid this unwanted phase, the amount of added rare earth La must be less than 0.6 wt%.展开更多
基金Supported by the National Natural Science Foundation of China(No.51165032)the Innovative Group of Science and Technology of College of Jiangxi Province(No.00008713)
文摘The effects of addition of La on the microstructure of as-cast ADC12 A1-Alloy were investigated by using optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscope （SEM）, and energy disperse spectroscopy （EDS）. The experimental results showed that the a-A1 and eutectic Si crystals were modified with the addition of 0.3 wt% La. The eutectic Si crystals showed a granular distribution. At the same time, the alloy possessed the best mechanical property. When more than 0.3 wt% La was added to ADC12 aluminum alloy, the microstructure of as-cast alloy was coarsening gradually with the increase of the content of La and the mechanical property decreased. The effect of rare earth La which was added in ADC 12 A1-Alloy for up to 0.9 wt% had been investigated in this study. The dendrites ofADC12 Al-alloy was refined obviously and the morphology of Si crystals showed a particle structure when the addition of La reached 0,3 wt%. Besides, the acicular La-rich intermetallics in the alloy deteriorated the mechanical property of alloy： To avoid this unwanted phase, the amount of added rare earth La must be less than 0.6 wt%.
