In Situ Observation on the Effects of Prior Martensite Formation on Nanostructured Low–Temperature Bainite Transformation
Abstract
:1. Introduction
2. Experiments
3. Results and Discussion
3.1. In Situ Observation of Bainitic Transformation Behavior for DIT and QBT
3.2. Microstructural Characteristics of Nanobainite Obtained by DIT and QBT
3.3. Comparison of Bainite Transformation Kinetics between DIT and QBT
4. Conclusions
- Prior martensite formation is found to accelerate the subsequent nanobainite transformation. The transformation occurs more quickly in QBT than in DIT.
- Bainitic laths formed adjacent to a prior martensite plate and grew up to austenites.
- Bainite phases formed both at the grain boundaries of the parent phase and inside the grains. Regarding the growth mode, bainite grows along the longitudinal direction and hardly grows along the lateral direction.
Author Contributions
Funding
Conflicts of Interest
References
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Nucleation Points | Isothermal Time, s | |
---|---|---|
DIT | QBT | |
1 | <280 | <120 |
3 | <357 | <144 |
5 | <379 | <217 |
10 | <560 | <236 |
20 | <674 | <303 |
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Zhou, W.; Hou, T.; Tao, L.; Wu, K. In Situ Observation on the Effects of Prior Martensite Formation on Nanostructured Low–Temperature Bainite Transformation. Metals 2018, 8, 818. https://doi.org/10.3390/met8100818
Zhou W, Hou T, Tao L, Wu K. In Situ Observation on the Effects of Prior Martensite Formation on Nanostructured Low–Temperature Bainite Transformation. Metals. 2018; 8(10):818. https://doi.org/10.3390/met8100818
Chicago/Turabian StyleZhou, Wen, Tingping Hou, Lang Tao, and Kaiming Wu. 2018. "In Situ Observation on the Effects of Prior Martensite Formation on Nanostructured Low–Temperature Bainite Transformation" Metals 8, no. 10: 818. https://doi.org/10.3390/met8100818