Gao Ka, Zhang Zan, Zhao Junliang, Sun Dejian, Wang Fu
School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou 450015, China.
Henan Key Laboratory of Aeronautical Material and Application Technology, Zhengzhou 450015, China.
Materials (Basel). 2020 Feb 24;13(4):1004. doi: 10.3390/ma13041004.
In an abruptly changing velocity under directional solidification, microstructures and the growth orientation of Al-AlCu eutectic lamellar were characterized. The change in solidification rate led to an interfacial instability, which results in a bifurcation of the eutectic lamella into new, refined lamellae. The growth orientation of the eutectic AlCu phase was also only in its (001) direction and more strongly oriented to the heat flow direction. The results suggest that the eutectic lamellar Al-AlCu bifurcation and the spacing adjustment may be caused by the rate determining lateral diffusion of the solutes after interfacial instability.
在定向凝固过程中速度突然变化的情况下，对Al-AlCu共晶片层的微观结构和生长取向进行了表征。凝固速率的变化导致界面不稳定，从而使共晶片层分叉成新的细化片层。共晶AlCu相的生长取向也仅在其(001)方向，并且更强烈地取向于热流方向。结果表明，共晶片层Al-AlCu的分叉和间距调整可能是由界面不稳定后溶质的速率决定横向扩散引起的。
