| COMPUTATIONAL SIMULATION |
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| Study on Flow Field and Process of New Stirrer for Stir Casting of SiCp/Al Composites |
| ZHANG Zhenlin1,2, ZHANG Zhifeng1, XU Jun1, ZHANG Hao1, MAO Weimin2
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1 National Engineering & Technology Research Center for Non-ferrous Metal Matrix Composite, General Research Institute for Non-ferrous Metals, Beijing 100088;
2 School of Materials Science and Engineering,University of Science and Technology Beijing, Beijing 100083 |
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Abstract Preparing SiCp/Al composites by stir casting process has the advantage of low cost and near-net shape. However, it is difficult to make SiC particles uniformly distribute in Al alloys, which is strongly dependent on the stirrer configuration and its casting process. In this study, a new paddle-grid compound stirrer was investigated to achieve powerful and uniform stirring by numerical and experimental methods. The velocity and flow field of the paddle-grid compound stirrer and the single stirrers were nume-rically compared, and then the optimal stir process using paddle-grid compound stirrer was experimentally done. The results showed that more uniform stir and more intense shear in large volume slurry could be achieved for the paddle-grid compound stirrer than the single stirrers. The flow field of paddle-grid compound stirrer was axial and radial circulation and the liquid level was smooth. The maximal fluid velocity was 3.9 m/s with the rotating speed of 500 r/min. The SiCp uniform distribution without pore was obtained in the production of 20wt%SiCp/A357 composites at the conditions of the optimal process parameters of stir temperature 610 ℃, stir speed 500 r/min and stir time 20 min.
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Published:
Online: 2018-05-08
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2017, Vol. 31 
