J. Mater. Sci. Technol. ›› 2022, Vol. 116: 83-93.DOI: 10.1016/j.jmst.2021.11.036

• Research Article • Previous Articles     Next Articles

3D morphological evolution and growth mechanism of proeutectic FeAl3 phases formed at Al/Fe interface under different cooling rates

Naifang Zhanga, Qiaodan Hua,*(), Zongye Dinga, Wenquan Lua, Fan Yangb, Jianguo Lia   

  1. aShanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, 200240 Shanghai, China
    bSchool of Mechanical Engineering, Shanghai Jiao Tong University, 200240 Shanghai, China
  • Received:2021-09-27 Revised:2021-11-22 Accepted:2021-11-24 Published:2022-01-29 Online:2022-07-26
  • Contact: Qiaodan Hu
  • About author:∗ E-mail address: qdhu@sjtu.edu.cn (Q. Hu).

Abstract:

The 3D morphologies and growth mechanisms of proeutectic FeAl3 at the Al/Fe interface under different cooling rates were studied by synchrotron X-ray tomography. With increasing cooling rate, FeAl3 crystals developed from faceted polygonal prism, plates with flat surface, thin ribbon-like with periodic undulating surface to non-faceted rods with radial dendrites in cross section, indicating a gradual interface growth mode transition from two-dimensional layer growth to continuous growth. At a higher cooling rate, twinning mechanism plays a leading role in the formation and growth of FeAl3. A link between the morphologies, twinning and crystallographic structure was established based on quantitative analyses on the 3D structures.

Key words: Solidification, 3D morphology, FeAl3 Intermetallic compounds, Cooling rate, Synchrotron radiation, Al/Fe interface