| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
The Structural Evolution of the Metastable Ni23B6 Phase during Rapid Solidification of Undercooled Ni-B Melts |
| Author(s) |
Lianjie Liu |
| On-Site Speaker (Planned) |
Lianjie Liu |
| Abstract Scope |
Solidification of metastable Ni23B6 phase and subsequent transformation into the stable phase has been investigated in undercooled Ni79.3B20.7 and Ni75B25 melts by cooling curve and microstructure. The Ni23B6 metastable phase solidifies as a substitute for the stable Ni3B phase above the critical undercooling ΔTc1 = 170 K and ΔTc2 = 240 K for Ni79.3B20.7 and Ni75B25 alloy, respectively. The structural evolution of metastable Ni23B6 phase in mushy zone is revealed during a two-step recalescence event. The final microstructure of the samples not only depends on undercooling, but also on the delay time of the second recalescence event. Decomposition of primary metastable phase accompanying with subsequent remelting and ripening plays an important role in the solidification microstructure formation. The delay time is a decisive parameter that does not affect the decomposition reaction, but it has a significant effect on the remelting and ripening. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Solidification, Phase Transformations, Copper / Nickel / Cobalt |