Henan Key Laboratory of Intelligent Manufacturing of Mechanical Equipment, Zhengzhou University of Light Industry, 450002, Zhengzhou, China.
National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite, Shanghai Jiao Tong University, 200240, Shanghai, China.
Department of Materials Science and Engineering, The Pennsylvania State University, 16802, University Park, PA, USA.
Abstract.
The growth of hexagonal columnar dendrite during directional solidification with respect to the multi-controlling parameters such as anisotropy, cooling rate, temperature gradient and orientation angle were investigated by a quantitative phase-field method, respectively. The simulation results show that the increase of anisotropy, cooling rate and temperature gradient can accelerate the solidification velocity of columnar dendrites. Among them, the cooling rate has the most significant effect on the solidification velocity of columnar dendrite. In contrast, the solidification velocity of columnar dendrite slows down with the increase of the orientation angle. Meanwhile, the primary dendrite spacing decreases with the increase of cooling rates and temperature gradient, and the primary dendrite arms are smooth. The primary dendrite spacing increases with the increase of anisotropy and orientation angle, which provides space for the development of secondary dendrite arms. In addition, the effects of cooling rate and temperature gradient on the solid volume fraction were also studied.
京公网安备 11010802027423号