Study of columnar-equiaxed transition and anaxial columnar dendrites growth of hypoeutectic alloy with synchrotron radiation

11th International Conference on X-ray Microscopy

Li, F.G.^1 ; Zhang, J.^1 ; Dong, Q.^1 ; Dai, Y.B.^1 ; Sun, B.D.^1 ; Xie, H.L.^2

School of Materials Science and Engineering, Shanghai Jiaotong University, Dongchuan Rd. 800#, Minhang District, Shanghai, 200240, China^1

Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Shanghai 215600, China^2

关键词: Columnar dendrites;    Columnar to equiaxed transition;    Columnar-equiaxed transition;    Dendrite morphology;    Hypoeutectic alloys;    Shanghai synchrotron radiation facilities;    Solidification process;    Thermal disturbance;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/463/1/012050/pdf
DOI  :  10.1088/1742-6596/463/1/012050

来源: IOP

【 摘 要 】

Among solidification processes, the columnar to equiaxed transition (CET) is critical component for formation either of microstructure or macrostructure. Directional solidification of Al-Cu alloy was performed at the BL13W beamline of Shanghai Synchrotron Radiation Facility (SSRF). The imaging results reveal that CET was provoked by external thermal disturbance. The fragment of dendrite tips were come from solute-rich-zone. And they floated to the mushy zone to form the equiaxed dendrites. As the conditions are suitable, a new dendrite morphology sprout and grow up, in which dendrites grow alongdirections in a binary Al-Cu alloy. These dendrites have no obvious primary arms and were named anaxial columnar dendrites.