Effects of Growth Rates on Directionally Solidified Microstructure of Al-Ni-Y Ternary Alloy

Rui Xu

doi:10.4028/www.scientific.net/AMR.562-564.477

Paper Titles

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Hard Thermosetting Polyurethane Plastic Degradable Test and its Influential Factors
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Effects of Growth Rates on Directionally Solidified Microstructure of Al-Ni-Y Ternary Alloy
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Preparation of La_1-xSr_xMnO₃ Materials by High Temperature Solid Phase Method
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The Microstructures and Mechanical Properties of a Novel Biomaterial Mg-Zn-Sr Alloy Sheet during Aging Treatment
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Synthesis of CuO Microspheres by the Simple Hydrothermal Method and their Optical Absorption Properties
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The Influence of the Hydrothermal Conditions on the Morphologies of β-Ni(OH)₂
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HomeAdvanced Materials ResearchAdvanced Materials Research Vols. 562-564Effects of Growth Rates on Directionally...

Effects of Growth Rates on Directionally Solidified Microstructure of Al-Ni-Y Ternary Alloy

Abstract:

The directional solidification of the ternary Al alloy with composition of 2.6 at%Ni, 0.9 at%Y and 96.5 at% Al was carried out under the temperature gradient of 5 K/mm and the droping velocities of 0.5 mm/min, 1 mm/min, 5 mm/min, 10 mm/min, and 25 mm/min. The microstructure of the Al-Ni-Y ternary alloy was also analyzed by X-ray diffraction and optical microscope. The experimental results show that the microstructures of the Al-Ni-Y ternary alloy are consisted of ª-Al₂, Al₃Ni and Y₄Ni₆Al₂₃ phase when the alloy was directionally solidified in all directionally solidified rates in the experiments. No primary -Al can be found in the sample with directionally solidified rate of 0.5 mm/min. When the rates higher than 1 mm/min, the primary ª-Al can be observed. The microstructure of the directionally solidified alloy becomes finer and the primary ª-Al is smaller gradually with the increasing of growth velocities when the dropping rate of directional solidification is higher than 5 min/min. Two eutectic structures, Y₄Ni₆Al₂₃ andª-Al eutectic and Al3Ni and ª-Al eutectic, can be found when the dropping rate is higher than 10 mm/min.