摘要
A modified Bridgman directional solidification technique was used to prepare Fe-Al-Ta eutectic in situ composites at different growth rates ranging from 6 to 80 gm/s. The directionally solidified Fe- Al-Ta eutectic composites are composed of two phases: Fe(Al,Ta) matrix phase, and Fe2Ta(Al) Laves phase. Solidification microstructure is affected by solidification rate. Microstructure of the Fe-Al-Ta eutectic alloy grown at 6.0 pm/s is broken-lamellar eutectic. Eutectic colonies are formed with the increase of the solidification rate. Microstructures are mainly composed of the lamellar or fibrous eutectic at the center of the colony and coarse lamellar eutectic zone at the boundary. Meanwhile, the inter-lamellar spacing (or the inter-rod spacing) is decreased. The spacing adjustments are also observed in Fe-Al-Ta eutectic alloy. The solid/liquid interface evolves from planar interface to shallow cellular interface, then to deep cellular, and finally to shallow cellular planar with the increase of the solidification rate.
A modified Bridgman directional solidification technique was used to prepare Fe-Al-Ta eutectic in situ composites at different growth rates ranging from 6 to 80 μm/s. The directionally solidified FeAl-Ta eutectic composites are composed of two phases: Fe（Al,Ta） matrix phase, and Fe2 Ta（Al） Laves phase. Solidification microstructure is affected by solidification rate. Microstructure of the Fe-Al-Ta eutectic alloy grown at 6.0 μm/s is broken-lamellar eutectic. Eutectic colonies are formed with the increase of the solidification rate. Microstructures are mainly composed of the lamellar or fibrous eutectic at the center of the colony and coarse lamellar eutectic zone at the boundary. Meanwhile, the inter-lamellar spacing（or the inter-rod spacing） is decreased. The spacing adjustments are also observed in Fe-Al-Ta eutectic alloy. The solid/liquid interface evolves from planar interface to shallow cellular interface, then to deep cellular, and finally to shallow cellular planar with the increase of the solidification rate.
基金
Funded by the National Natural Science Foundation of China(No.51201121)
2015 Science and Technology Foundation for Selected Overseas Chinese Scholars of Shaanxi Province,Key Industry Innovation Chain(group)Project of Shaanxi Province(No.2019ZDLGY 04-04)International Science
Technology Cooperation and Exchange Program of Shaanxi Province(No.2016KW-055)
Research Project of Shaanxi Engineering Technology Research Center for Wear-resisting Materials(No.2016NMZX03)
