Modification of primary a-Al, eutectic silicon and β-AlsFeSi phases in as-cast AISil0Cu3 alloys with （La＋Yb） addition

• Published in: 中国稀土学报：英文版 2015, Vol.33 (9), p.995-1003
• Main Author: 李正华 闫洪
• Format: Article
• Language: English
• Subjects: X射线衍射仪; 中间合金; 共晶硅; 原铝; 扫描电子显微镜; 改性
• ISSN: 1002-0721; 2509-4963

The study systematically investigated the effects of master alloy addition containing rare earth elements La and Yb on the microstructures characteristic and tensile properties of A1Sil0Cu3 alloy. It was studied by means of optical microscopy, X-ray diffraction, scanning electron microscopy, energy diffraction spectnam and differential thermal analyzer. The results showed that the ad-dition of （La＋Yb） obviously reduced the sizes of the primary a-Al phase and eutectic Si particles as well as 13-A15FeSi phase and im- proved the morphology of the primary a-A1 phase and eutectic Si particles. The optimum addition of（La＋Yb） addition was 0.6 wt.%. Comparing the 0.6 wt.% （La＋Yb） modified A1Sil0Cu3 alloy with the unmodified alloy, it was found that the mean diameter, mean area and SADS of primary a-A1 phase were decreased by 50.80%, 75.74% and 50.83% respectively; the aspect ratio, size （length） and mean area of eutectic Si particles were decreased by 66.30%, 81.78% and 78.99%, respectively, and the average size of the β-AlsFeSi phase was 16.4 pro. In addition, the addition of （La＋Yb） greatly improved the tensile properties ofA1Si 10Cu3 alloy, especially in the ultimate tensile strength and elongation as a result of the significant improvement in microstructure.