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 me...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.展开更多
Nonstable growth of Al-Si eutectic in constrained condition has been investigated by means of change of the withdrawing rate in an unidirectional solidification system,In constant acceleration growth,a retarded effect...Nonstable growth of Al-Si eutectic in constrained condition has been investigated by means of change of the withdrawing rate in an unidirectional solidification system,In constant acceleration growth,a retarded effect of response of eutectic interflake spacing on the growth rate has been observed.The response mechanisms are cluster-branching and local termination extension of Si-phase.In constant deceleration growth,the cluster-branching and termina- tion mechanisms of silicon still control adjustment of the interflake spacing,but the spacing is determined by the initial growth rate and does not respond to the decreasing growth rate.展开更多
基金supported by the National Natural Science Foundation of China(51364035,51165032)Ministry of Education tied up with the Special Research Fund for the Doctoral Program for Higher School(20133601110001)Loading Program of Science and Technology of College of Jiangxi Province(KJLD14003)
文摘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.
文摘Nonstable growth of Al-Si eutectic in constrained condition has been investigated by means of change of the withdrawing rate in an unidirectional solidification system,In constant acceleration growth,a retarded effect of response of eutectic interflake spacing on the growth rate has been observed.The response mechanisms are cluster-branching and local termination extension of Si-phase.In constant deceleration growth,the cluster-branching and termina- tion mechanisms of silicon still control adjustment of the interflake spacing,but the spacing is determined by the initial growth rate and does not respond to the decreasing growth rate.
基金Projects(51971040,51701029,51671041,51531002) supported by the National Natural Science Foundation of ChinaProject(2016YFB0301100) supported by the National Key Research and Development Program of China+2 种基金Projects(2018T110943,2017M620410) supported by the China Postdoctoral Science FoundationProject(Xm2017010) supported by the the Chongqing Postdoctoral Scientific Research Foundation,ChinaProject(2018CDGFCL005) supported by the Fundamental Research Funds for the Central Universities,China
