Study on Bainitic Transformation by Dilatometer and In Situ LSCM
Abstract
:1. Introduction
2. Materials and Experimental Procedures
3. Results and Analysis
3.1. Transformation Kinetics
3.2. In Situ Observation
3.3. Relationship between Transformation, Kinetics and Microstructure
4. Conclusions
- Carbide-free bainitic steel requires a long incubation period, because Si and Al hinder C diffusion, making the distribution of carbon atoms more homogeneous. Carbide-bearing bainitic steel exhibits a long transformation time.
- Bainitic ferrite plates nucleate preferentially on the grain boundary and new plates nucleate on previously formed ones. Compared to nucleation at grain boundaries, nucleation on previously formed bainitic ferrite is faster in some grains.
- The location and number of nucleation points have an important influence on the thickness of bainitic ferrite. The greater the number of positions of preferential nucleation on the original austenite grain boundary in the early transformation stage, the greater the thickness of the bainitic ferrite.
Author Contributions
Funding
Conflicts of Interest
References
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Materials | C | Si | Mn | Cr | Ni | Mo | Al |
---|---|---|---|---|---|---|---|
Carbide-free bainite | 0.34 | 1.48 | 1.52 | 1.15 | 0.93 | 0.40 | 0.71 |
Carbide-bearing bainite | 0.34 | 0.01 | 1.61 | 1.24 | 0.96 | 0.45 | 0.04 |
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Long, X.; Zhang, F.; Yang, Z.; Zhang, M. Study on Bainitic Transformation by Dilatometer and In Situ LSCM. Materials 2019, 12, 1534. https://doi.org/10.3390/ma12091534
Long X, Zhang F, Yang Z, Zhang M. Study on Bainitic Transformation by Dilatometer and In Situ LSCM. Materials. 2019; 12(9):1534. https://doi.org/10.3390/ma12091534
Chicago/Turabian StyleLong, Xiaoyan, Fucheng Zhang, Zhinan Yang, and Ming Zhang. 2019. "Study on Bainitic Transformation by Dilatometer and In Situ LSCM" Materials 12, no. 9: 1534. https://doi.org/10.3390/ma12091534