Impacts of Modification of Alloying Method on Inclusion Evolution in RH Refining of Silicon Steel
Abstract
:1. Introduction
2. Experimental Procedure
3. Results and Discussion
3.1. Analysis of Oxide Inclusions in RH Refining
3.2. Quality and Cost Analysis of the Pre-Alloying Innovation
4. Conclusions
- (1)
- MnO-FeO inclusions formed as a by-product of pre-alloying. The evolution of the oxide is as follows: spherical Fe-rich 3FeO·MnO becomes shelled Fe-rich, low-melting point 3FeO·MnO in the core and Mn-rich, high-melting point FeO·zMnO on the surface of the shell. Some of shelled inclusions become spherical Mn-rich FeO·zMnO. These inclusions are eliminated at the beginning of the degassing stage.
- (2)
- Inclusion evolution in pre-alloying RH refining is different from that in conventional RH refining, but the ingots produced by pre-alloying are of a quality that meets or exceeds industry-wide specifications with respect to quality, carbon content, and inclusion size.
- (3)
- When pre-alloying is used, the amount of high-cost, low-carbon FeMn alloy required during the deoxidization/alloying stage is reduced by 20%, thus reducing the overall cost of the process by 3%.
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Process | Point | C | Si | Mn | Als |
---|---|---|---|---|---|
Pre-alloying process | S1 | 4.4 × 10−2 | 2.1 × 10−3 | 6.1 × 10−2 | 2.0 × 10−3 |
S2 | 1.0 × 10−3 | 2.3 × 10−3 | 4.9 × 10−2 | 1.9 × 10−3 | |
S3 | 5.0 × 10−3 | 2.6 × 10−1 | 3.0 × 10−1 | 3.3 × 10−1 | |
S4 | 1.0 × 10−3 | 2.6 × 10−1 | 3.6 × 10−1 | 2.8 × 10−1 | |
Conventional alloying process | End of RH | <5.0 × 10−3 | 2.5 × 10−1 | 3.5 × 10−1 | 2.8 × 10−1 |
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Li, F.; Li, H.; Zheng, S.; You, J.; Han, K.; Zhai, Q. Impacts of Modification of Alloying Method on Inclusion Evolution in RH Refining of Silicon Steel. Materials 2017, 10, 1206. https://doi.org/10.3390/ma10101206
Li F, Li H, Zheng S, You J, Han K, Zhai Q. Impacts of Modification of Alloying Method on Inclusion Evolution in RH Refining of Silicon Steel. Materials. 2017; 10(10):1206. https://doi.org/10.3390/ma10101206
Chicago/Turabian StyleLi, Fangjie, Huigai Li, Shaobo Zheng, Jinglin You, Ke Han, and Qijie Zhai. 2017. "Impacts of Modification of Alloying Method on Inclusion Evolution in RH Refining of Silicon Steel" Materials 10, no. 10: 1206. https://doi.org/10.3390/ma10101206
APA StyleLi, F., Li, H., Zheng, S., You, J., Han, K., & Zhai, Q. (2017). Impacts of Modification of Alloying Method on Inclusion Evolution in RH Refining of Silicon Steel. Materials, 10(10), 1206. https://doi.org/10.3390/ma10101206