Effect of Bubbles on Crystallization Behavior of CaO–SiO2 Based Slags
Abstract
:1. Introduction
2. Materials and Methods
2.1. Material Preparation
2.2. Experimental Methods
3. Results and Discussion
3.1. Microstructure
3.2. Crystal Phase
3.3. Crystalline Fraction, Slag Film Thickness, and Surface Roughness of Slag Film
3.4. Structure of Molten Slags
3.5. TTT and CCT
3.5.1. TTT
3.5.2. CCT
3.6. Crystalline Kinetics
4. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Number | CaCO3 | CaO | SiO2 | MgO | Al2O3 | Na2SO4 | Na2CO3 | Na2O | F |
---|---|---|---|---|---|---|---|---|---|
A | 0 | 45.2 | 33.4 | 0.8 | 5.0 | 0 | 0 | 8.0 | 7.6 |
B1 | 14.4 | 37.2 | 33.4 | 0.8 | 5.0 | 0.5 | 3.1 | 6.0 | 7.6 |
B2 | 28.6 | 29.2 | 33.4 | 0.8 | 5.0 | 2.0 | 5.4 | 4.0 | 7.6 |
B3 | 42.9 | 21.2 | 33.4 | 0.8 | 5.0 | 3.5 | 7.6 | 2.0 | 7.6 |
Sample Number | Crystalline Fraction (%) | Slag Film Thickness (mm) | Surface Roughness (um) | |
---|---|---|---|---|
Wide Side | Narrow Side | |||
A | 69.3 | 2.9 | 3.2 | 32.6 |
B1 | 80.3 | 3.3 | 3.6 | 47.1 |
B2 | 87.1 | 3.5 | 3.8 | 53.4 |
B3 | 73.6 | 3.2 | 3.5 | 40.9 |
Raman Bands | Raman Shift (cm−1) | Peak Area Ratio (%) | ||||||
---|---|---|---|---|---|---|---|---|
A | B1 | B2 | B3 | A | B1 | B2 | B3 | |
Symmetric stretching Si-O− of Q0 | 866 | 860 | 869 | 863 | 10.88 | 13.68 | 19.38 | 21.18 |
Symmetric stretching Si-O− of Q1 | 905 | 905 | 902 | 909 | 17.02 | 20.03 | 38.84 | 19.84 |
Symmetric stretching Si-O− of Q2 | 959 | 966 | 953 | 951 | 58.99 | 59.21 | 36.95 | 52.41 |
Symmetric stretching Si-O− of Q3 | 1055 | 1051 | 1046 | 1049 | 13.11 | 7.08 | 4.91 | 6.57 |
R2 | 0.9981 | 0.9987 | 0.9979 | 0.9985 | - | - | - | - |
Mold Fluxes | Temperature/K | n | lnk |
---|---|---|---|
A | 1173 | 1.54 | −5.12 |
1223 | 2.01 | −4.71 | |
1273 | 2.10 | −4.18 | |
1323 | 2.11 | −4.98 | |
B1 | 1173 | 2.28 | −3.68 |
1223 | 2.44 | −2.41 | |
1273 | 2.61 | −2.22 | |
1323 | 2.62 | −1.59 | |
B2 | 1173 | 2.99 | −2.49 |
1223 | 3.02 | −2.13 | |
1273 | 3.08 | −1.86 | |
1323 | 3.09 | −1.18 | |
B3 | 1173 | 2.11 | −4.74 |
1223 | 2.17 | −4.26 | |
1273 | 2.26 | −3.77 | |
1323 | 2.28 | −4.31 |
Grow Mode | Crystallization Mode | |
---|---|---|
Diffusion Controlled | Interface Reaction Controlled | |
Constant nucleation rate | - | - |
3-dimensional growth | 2.5 | 4 |
2-dimensional growth | 2 | 3 |
1-dimensional growth | 1.5 | 2 |
Instantaneous nucleation | - | - |
3-dimensional growth | 1.5 | 3 |
2-dimensional growth | 1 | 2 |
1-dimensional growth | 0.5 | 1 |
Surface nucleation | 0.5 | 1 |
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Gu, S.; Wen, G.; Ding, Z.; Guo, J.; Tang, P.; Liu, Q. Effect of Bubbles on Crystallization Behavior of CaO–SiO2 Based Slags. Metals 2019, 9, 193. https://doi.org/10.3390/met9020193
Gu S, Wen G, Ding Z, Guo J, Tang P, Liu Q. Effect of Bubbles on Crystallization Behavior of CaO–SiO2 Based Slags. Metals. 2019; 9(2):193. https://doi.org/10.3390/met9020193
Chicago/Turabian StyleGu, Shaopeng, Guanghua Wen, Zequan Ding, Junli Guo, Ping Tang, and Qiang Liu. 2019. "Effect of Bubbles on Crystallization Behavior of CaO–SiO2 Based Slags" Metals 9, no. 2: 193. https://doi.org/10.3390/met9020193