| Cite this article as: |
Dawei Cai, Li Zhang, Wanlin Wang, Lei Zhang, and Il Sohn, Dissolution of TiO2 and TiN inclusions in CaO–SiO2–B2O3-based fluorine-free mold flux, Int. J. Miner. Metall. Mater., 30(2023), No. 9, pp.1740-1747. https://dx.doi.org/10.1007/s12613-023-2622-9
|
Titanium (Ti) is an effective alloying element added to steel to substantially improve its physical properties, such as toughness, weldability, and formability. The nanoscale TiC, TiN, and Ti(C,N) precipitates are easily formed in liquid steel, and they play an essential role in fine grain and precipitation strengthening [1–3]. However, during the casting process of Ti-containing steels, the Ti-bearing inclusions of TiO2 and TiN grow into large particles in the presence of sufficient O and N [4–5] and gather at the submerged nozzle, thereby resulting in nozzle clogging [6–9]. However, some inclusions float to the steel–slag interface and are absorbed by the molten mold flux covering the liquid steel surface. Here, two reactions can easily occur, as shown in Eqs. (1) and (2) [10–11], resulting in the performance deterioration of the mold flux and the formation of floaters [4,12], which negatively affects the smoothness of the casting process as well as the cast slab quality.
| (TiO2)+(CaO)→CaTiO3 | (1) |
| TiN+(SiO2)→[Si]+(TiO2)+1/2N2↑ | (2) |
Mold flux plays essential metallurgical functions, including absorbing the inclusions floating from liquid steel [13–14]. Previous studies [15–17] suggest that molten mold fluxes can effectively absorb the floating TiO2 inclusions because of their high solubility in molten slag. Nevertheless, TiN inclusions are mainly dispersed in molten slag as solid particles because their solubility is less than 0.5wt% [12]. The absorption of a small amount of TiO2 inclusions reduces the viscosity and improves the fluidity of molten slag. When that amount exceeds 10wt%, the viscous flow properties deteriorate dramatically because a large amount of precipitated CaTiO3 crystals cause the slag to be in a solid–liquid mixed state [12,18–19]. However, TiN inclusions need to be initially oxidized by SiO2, MnO, Fe2O3, etc., and then they can be effectively absorbed [4,10–11,20]. These oxidation reactions will produce N2 gas, which tends to absorb considerable heat, decreasing the surface temperature of liquid steel and forming surface crust such that the solidified shell is encased with inclusions, bubbles, and slag [20–21].
Previous studies [10,22] indicated that B2O3 can lower the activation energy of the molten slag required to dissolve inclusions, facilitating the absorption of TiO2 and TiN inclusions. Additionally, B3+ can passivate the crystallization ability of TiO2 to suppress the precipitation of perovskite in molten slag [23–26]. Furthermore, B2O3 is considered one of the ideal choices to replace fluorine in mold flux because it is an effective flux similar to CaF2 and can substantially reduce the melting temperature and viscosity of the mold flux [14,27–31]. Specifically, B2O3-containing fluorine-free (F-free) mold flux has better interfacial wettability than the traditional fluorine-containing mold flux, which benefits the absorption of inclusions [30]. Therefore, considering the need for the production of Ti-containing steels with better product quality and lower environmental impact, the dissolution mechanism of Ti-bearing inclusions in a CaO–SiO2–B2O3-based F-free mold flux system must be understood. Thus, in this work, the dissolution behavior of TiO2 and TiN inclusions in molten F-free mold flux was explored by the single hot thermocouple technology (SHTT) via in situ observation. Additionally, their dissolution mechanism was discussed in depth on the basis of analyses from scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS).
The major chemical compositions of the designed CaO–SiO2–B2O3-based fluorine-free mold flux are listed in Table 1. The basicity (CaO/SiO2 mass ratio) is 1.0, and the key component of B2O3 content is 6wt%. The sample was prepared using analytical-grade chemical reagents, including CaO (Macklin, 99.9%), SiO2 (Macklin, 99.99%), Al2O3 (Macklin, 99.99%), Li2CO3 (Macklin, 99.9%), and B2O3 (Aladdin, 99.9%). The weighed reagents were well mixed mechanically and placed in a high-purity graphite crucible to be melted by an induction furnace. The reagents were heated to 1500°C to melt and held for 30 min to homogenize the compositions. Then, the melt was rapidly poured into water to obtain a glassy sample with uniform composition. Finally, the quenched sample was dried and ground into a powder for the experiments. Before the experiments, the powder sample was examined by X-ray diffraction (XRD). The pattern in Fig. 1 shows no significant characteristic peak, indicating that the prepared sample is the expected glassy slag.
| CaO/SiO2 mass ratio | Content / wt% | ||||
| CaO | SiO2 | Al2O3 | Na2O | B2O3 | |
| 1.0 | 37.5 | 37.5 | 5 | 10 | 6 |
DownLoad:
CSV
Moreover, the used TiO2 inclusions (Fig. 2(a)) are loose and porous particles of rutile (PDF #21-1276), where the coordination number of the Ti atom is six, and the basic structural unit is octahedral [TiO6]8− [32]. The TiN inclusion (Fig. 2(b)) is a dense particle whose XRD pattern matches well with the standard peak of the PDF #38-1420 card. Based on the structural analysis, the coordination number of the Ti atom is also six [33].
SHTT can accurately control the temperature from room temperature to 1800°C with a temperature fluctuation within ±10°C using a B-type thermocouple, which is schematized in Fig. 3(a). Furthermore, the cooling rate can reach a maximum of 30°C/s, preserving the high-temperature state of the melt to a certain extent. For the inclusion dissolution experiment by SHTT, ~40 mg of powder slag was first mounted on the B-type thermocouple and heated to 1500°C for 3 min to homogenize the composition of the melt and minimize the bubbles. Then, an inclusion ball with a size of ~500 μm was held by a tweezer, placed directly above the molten slag, and dropped into the molten slag from the tweezer. Finally, the inclusions were dissolved in the molten slag when the B-type thermocouple was held at 1500°C for 10 min. The entire experiment was performed under an air atmosphere, and the dissolution process was in situ recorded using a microscope combined with a high-definition camera. Moreover, to analyze the state at different dissolution times, the corresponding sample at 1500°C was rapidly quenched to room temperature at a maximum cooling rate of 30°C/s for further analysis. The temperature control profile for this experiment is shown in Fig. 3(b).
The quenched sample from the SHTT experiment was embedded in resin and processed with a standard set of metallographic sample preparation procedures for scanning electron microscopy (SEM, Mira3 LMH, Tescan, Czech Republic) observation with energy dispersive spectrometry (EDS, Ultim Max 40, Oxford, United Kingdom) analysis. The observation was performed with a backscattered electron model at an accelerating voltage of 15 kV and a working distance of ~15 mm. Meanwhile, the elemental information of the phases was obtained by point analysis with EDS. Additionally, the valence state and coordination information of the dissolved Ti was tested by X-ray photoelectron spectroscopy (XPS, Escalab Xi+, Thermo Fisher Scientific, America). The fine spectrum of Ti 2p of the same bulk sample as in the SEM test was collected with an Al Kα-focused monochromator at a passing energy of 20.0 eV. The XPS spectrum was calibrated with the C 1s peak at a reference binding energy of 284.8 eV.
Fig. 4 displays the in situ real-time images of the dissolution process of a TiO2 inclusion in molten slag at 1500°C. When the TiO2 inclusion is added to the molten slag, many bubbles are generated around it because the TiO2 particles are a loose and porous structure. Subsequently, the TiO2 particles are rapidly dispersed and effectively dissolved in the molten slag, and the bubbles disappear. When the dissolution time is 76 s, the TiO2 particles are completely dissolved, suggesting that the molten slag only takes 76 s to effectively dissolve the TiO2 inclusion.
To analyze the state at different dissolution times, the samples at 5, 15, and 131 s were rapidly quenched (30°C/s) for further analysis, representing the states of initial, partial, and complete dissolution, respectively. Fig. 5 shows the SEM images and EDS results of these quenched samples. The sample at a dissolution time of 5 s (Fig. 5(a)) has white substances distributed on its edge, and these substances are surrounded by irregular depressions observed by further magnification. EDS analysis indicate that the main components of the smooth substrate (point A) are Ca, Si, and O, which are the main components of the slag. The white substance (point B) mainly comprises Ca, Ti, and O, and the Ca/Ti atomic ratio is approximately 1:1. It is therefore inferred that this substance is a CaTiO3 crystal phase, which is consistent with our previous research [10,12]. Additionally, the irregular depressions may be caused by the undissolved TiO2 particles falling from the slag during sample preparation. For the sample at 15 s (Fig. 5(b)), a small amount of CaTiO3 crystal surrounded by irregular depressions can still be seen in the smooth slag. Fig. 5(c) demonstrates that the molten slag at a dissolution time of 131 s was rapidly quenched to a glassy phase with uniform composition and without any crystal precipitation as well as no traces of the undissolved TiO2 particle falling off. This finding indicates that the added TiO2 inclusion has been completely and effectively dissolved by the molten slag at this time.
The samples were also examined with XPS analysis to analyze the state of Ti dissolved in the molten slag. Generally, Ti has two typical states in the melt, namely, tetrahedral [TiO4]4− and octahedral [TiO6]8− structures, which can be obtained by fitting and deconvoluting the Ti 2p XPS fine spectrum within a binding energy range of 467 to 456 eV. The primary Ti 2p3/2 peak is located at 459.2 eV and is more intense and has a smaller quantitative error than the secondary Ti 2p1/2 peak located at 464.4 eV. Thus, the two characteristic peaks at 459.5 and 458.3 eV for the tetrahedral [TiO4]4− and octahedral [TiO6]8− structures, respectively, can be fitted and deconvoluted from the primary Ti 2p3/2 peak [34]. The Ti 2p spectra of the samples at different dissolution times and their deconvoluted results are displayed in Fig. 6.
For the sample with the TiO2 inclusions for dissolving time of 5 s, tetrahedral [TiO4]4− is the main form of Ti in the melt. However, the spectrum has many interference peaks, and the intensity of the main peak is relatively weak because the amount of TiO2 dissolved in the molten slag at this time is minimal. The intensity of the main peak is considerably enhanced for the sample at a dissolution time of 15 s, and the area proportion of the deconvoluted peak assigned to tetrahedral [TiO4]4− and octahedral [TiO6]8− is ~70.92% and ~29.08%, respectively. When the added TiO2 inclusion was completely dissolved in the molten slag, the proportion of the peak assigned to tetrahedral [TiO4]4− and octahedral [TiO6]8− slightly decreased to 67.11% and accordingly increased to 32.89%, respectively. This increase may be due to the added TiO2 inclusion belonging to the rutile structure, in which the Ti form is [TiO6]8− octahedral. Thus, when a small amount of TiO2 is dissolved in the molten slag, most of the octahedral [TiO6]8− will be converted to the networker tetrahedral [TiO4]4−, as shown in Eq. (3) [35]:
| [TiO6]8−↔[TiO4]4−+2O2− | (3) |
As the dissolution time increases, increasingly more TiO2 inclusions are dissolved, and the reaction gradually weakens with the accumulation of the tetrahedral [TiO4]4− product in the molten slag. Therefore, as more TiO2 inclusions are dissolved in the molten slag, octahedral [TiO6]8− and tetrahedral [TiO4]4− contents increase, but the proportion of tetrahedral [TiO4]4− is slightly reduced.
On the basis of the above analysis, the mechanism for the dissolution of TiO2 inclusions in molten CaO–SiO2–B2O3-based F-free slag can be discussed as follows.
An added rutile TiO2 inclusion has a loose and porous structure, and it will quickly disperse and come into contact fully with the molten slag. Then, the original octahedral [TiO6]8− of the TiO2 inclusion will be destroyed and converted to the networker tetrahedral [TiO4]4− in the present alkaline slag system. Additionally, the formed tetrahedral [TiO4]4− tends to connect with other network structures, such as tetrahedral [SiO4]4− and trihedral [BO3]3−, to form more stable titanosilicate and titanoborate structures [35–37]. This behavior is conducive to the transformation of octahedral [TiO6]8− to tetrahedral [TiO4]4− as well as the effective dissolution of TiO2 inclusions.
However, during the dissolution process of a TiO2 inclusion, the TiO2 particles that have not had time to dissolve in the slag will act as heterogeneous nucleating agents, lowering the energy for crystal nucleation [38–40]. The octahedral [TiO6]8− monomer and Ca2+ ions in the molten slag aggregate around the nucleating agent TiO2 to form CaTiO3 crystals. Thus, the CaTiO3 crystal is surrounded by TiO2 particles, which can be seen in the SEM images of the sample at dissolution times of 5 and 15 s in Fig. 5(a) and (b), respectively. With the gradual increase in dissolved TiO2, the octahedral [TiO6]8− content increases in the melt, but the precipitation of CaTiO3 crystals decreases because of the lack of TiO2 particles as nucleating agents. On the other hand, the converted tetrahedral [TiO4]4− connects with other network structures to increase the polymerization degree of the melt structure, which also impedes nucleation and crystallization in the slag. Consequently, no crystals precipitate in the molten slag when the TiO2 inclusion is completely dissolved, although the molten slag contains many octahedral [TiO6]8− monomers at this time.
Fig. 7 displays the in situ real-time images of the dissolution process of a TiN inclusion in molten slag at 1500°C. Obvious bubbles can also be observed because of the air brought in when the TiN inclusion is added to the molten slag. As the dissolution proceeds, the TiN inclusion disperses and is slowly dissolved, which is accompanied by the production of bubbles. This behavior is observed because the TiN inclusion needs to be oxidized first and then can be dissolved in the molten slag, which produces N2 gas. Furthermore, the dissolution rate is considerably lower than that of the TiO2 inclusion, and many inclusions are undissolved until the dissolution time is 209 s. At a dissolution time of 250 s, the solid aggregates increase instead, and much new precipitate is apparent in the further magnification of the image. At this time, bubbles are still produced, indicating that TiN dissolution is still slowly progressing. After 300 s, the particles have distributed throughout the molten slag and are difficult to dissolve. Thus, the state of the melt becomes a solid–liquid mixture.
The morphologies of the quenched samples at different dissolution times was analyzed using SEM and EDS, as shown in Fig. 8. The SEM image of the sample at a dissolution time of 5 s (Fig. 8(a)) reveals that many pores are distributed throughout the slag, where the large bubbles are mainly caused by the air brought in, and the small bubbles are produced by the dissolution reaction. Additionally, the undissolved TiN particles can be observed, particularly at the edge of the slag. At a dissolution time of 120 s (Fig. 8(b)), the sample still contains pores and solid substances, but the pores are mainly smaller in size and substantially reduced in number, suggesting that the oxidation of the TiN inclusion is subsiding. Further magnification shows that the solid substance comprises precipitate (point A) larger than 10 μm and particles (point B) with a size of 1–5 μm, which is proved by EDS analysis to be the precipitated CaTiO3 crystals and the undissolved TiN inclusion, respectively. The sample with a dissolution time of 300 s (Fig. 8(c)) has no obvious TiN inclusions and pores and instead mainly contains many larger-sized CaTiO3 crystals. Moreover, the slag contains a certain amount of nitrogen, as seen in the EDS result of point C, suggesting that a certain amount of nitrogen is dissolved in the molten slag. Additionally, dissolved nitrogen tends to increase the liquidus temperature of slags [41–42], which may explain why the precipitated crystals of CaTiO3 are stable and growing. These results indicate that TiN can also be dissolved by the molten CaO–SiO2–B2O3-based F-free mold flux, but it will promote the precipitation of CaTiO3 crystals and stably exist in the molten slag.
Similarly, the state of Ti dissolved in the molten slag was also analyzed using XPS, and the results are shown in Fig. 9. The intensity of the major peak at 459.2 eV in the Ti 2p XPS pattern is very weak for the sample with dissolution times of only 5 and 120 s, and interference peaks are numerous. Therefore, the semi-quantitative fitting and deconvolution analysis of the weak major peak are not informative. This result is due to the small amount of dissolved Ti in the molten slag at this time. The intensity of the major peak at 459.2 eV is greatly enhanced for the sample with dissolution time of 300 s, which enables efficient fitting and deconvolution for further semi-quantitative analysis. Thus, the area proportions of the deconvoluted peaks assigned to tetrahedral [TiO4]4− and octahedral [TiO6]8− are ~58.98% and ~41.02%, respectively. Although the Ti atoms in the added TiN inclusions are 6-coordinated, the oxidation of TiN consumes a large amount of O2− ions during the dissolution process, promoting the transformation of octahedral [TiO6]8− to tetrahedral [TiO4]4−, as shown in Eq. (3). Thus, the proportion of tetrahedral [TiO4]4− in the molten slag is higher than that of octahedral [TiO6]8−.
The mechanism of the dissolution of a TiN inclusion in molten CaO–SiO2–B2O3-based F-free slag can be deduced from the results of SEM and XPS analyses as follows.
TiN has very low solubility in molten slag, so most of the TiN inclusions need to be oxidized to form tetrahedral [TiO4]4− and octahedral [TiO6]8− structures and produce N2 gas [43–45]. Thus, when the TiN inclusion is added to the molten slag for 5 s, the TiN particle is oxidized to produce a large amount of N2 gas and also generates many tetrahedral [TiO4]4− and octahedral [TiO6]8− structures. The network tetrahedral [TiO4]4− will also link with the existing silicate and borate structures to form more stable titanosilicate and titanoborate structures [35–36], while octahedral [TiO6]8− is mainly present in the melt as a monomer.
With an increase in the dissolution time to 120 s, the oxidation and dissolution of the TiN inclusion continue, but the reaction rate is relatively low. Additionally, CaTiO3 crystals have precipitated at this time because N2 gas production causes a sudden temperature drop in the molten slag, and the bubbles act as a nucleation point to reduce the energy barrier for crystallization and promote the heterogeneous nucleation in the melt [46–47]. On the other hand, the dissolved Ti accumulates a certain amount of octahedral [TiO6]8− monomers. Then, CaTiO3 crystals easily nucleate and grow on the surface of the bubbles with sufficient octahedral [TiO6]8− monomers and Ca2+ ions in the melt. When the TiN particles are completely dissolved at a dissolution time of 300 s, no obvious bubbles and TiN particles are apparent, and the newly formed CaTiO3 crystals are greatly reduced because of the absence of the nucleation points of the bubbles. However, the precipitated CaTiO3 crystals will be stable in the molten slag and continue to grow because of the increase in the liquidus temperature of the molten mold flux.
The dissolution behavior of TiO2 and TiN inclusions in molten CaO–SiO2–B2O3-based fluorine-free mold flux was investigated in situ using SHTT, and the dissolution mechanism was explored using XPS and SEM with EDS. The main conclusions are summarized as follows.
(1) TiO2 inclusions are effectively dissolved in the molten CaO–SiO2–B2O3-based slag within 76 s because most of the original octahedral [TiO6]8− structures are destroyed and converted to tetrahedral [TiO4]4−. Moreover, although a large amount of Ti has been dissolved in the molten slag, CaTiO3 crystals do not readily precipitate without heterogeneous nucleating agents.
(2) For the dissolution of TiN inclusions, TiN particles need to be oxidized and dissolved in the molten slag in tetrahedral [TiO4]4− and octahedral [TiO6]8− structures. Consequently, the dissolution rate of TiN inclusions is substantially lower than that of TiO2 inclusions.
(3) CaTiO3 crystals tend to precipitate and exist stably in the molten slag when TiN inclusion is dissolved, causing the melt to finally be in a solid–liquid mixed state. Because the produced N2 gas acts as a nucleation point, it promotes the heterogeneous nucleation of CaTiO3 crystals with sufficient octahedral [TiO6]8− monomers and Ca2+ ions.
This work was financially supported by the Fellowship of China National Postdoctoral Program for Innovative Talents (No. BX20220357) and the National Science Foundation of China (No. 52130408).
Il Sohn is an editorial board member for this journal and was not involved in the editorial review or the decision to publish this article. The authors state no conflict of interest in publishing this work.
| [1] |
H.W. Yen, C.Y. Chen, T.Y. Wang, C.Y. Huang, and J.R. Yang, Orientation relationship transition of nanometre sized interphase precipitated TiC carbides in Ti bearing steel, Mater. Sci. Technol., 26(2010), No. 4, p. 421. DOI: 10.1179/026708309X12512744154207
|
| [2] |
L.D. Xing, J.L. Guo, X. Li, et al., Control of TiN precipitation behavior in titanium-containing micro-alloyed steel, Mater. Today Commun., 25(2020), art. No. 101292. DOI: 10.1016/j.mtcomm.2020.101292
|
| [3] |
Y.F. Shen, C.M. Wang, and X. Sun, A micro-alloyed ferritic steel strengthened by nanoscale precipitates, Mater. Sci. Eng. A, 528(2011), No. 28, p. 8150. DOI: 10.1016/j.msea.2011.07.065
|
| [4] |
Z. Chen, M. Li, X.F. Wang, S.P. He, and Q. Wang, Mechanism of floater formation in the mold during continuous casting of Ti-stabilized austenitic stainless steels, Metals, 9(2019), No. 6, art. No. 635. DOI: 10.3390/met9060635
|
| [5] |
T.F. Zhao, X. Zheng, D.J. Huang, Z.H. Zhu, and Z.H. Yin, Thermodynamic research on the precipitation of Ti2O3, TiN and TiC in continuous casting of titanium microalloyed steel, J. Phys.: Conf. Ser., 2076(2021), No. 1, art. No. 012077. DOI: 10.1088/1742-6596/2076/1/012077
|
| [6] |
J.Y. Li, G.G. Cheng, Q. Ruan, J.X. Pan, and X.R. Chen, Characteristics of nozzle clogging and evolution of oxide inclusion for Al-killed Ti-stabilized 18Cr stainless steel, Metall. Mater. Trans. B, 50(2019), No. 6, p. 2769. DOI: 10.1007/s11663-019-01708-8
|
| [7] |
L.M. Cheng, L.F. Zhang, Y. Ren, and W. Yang, Clogging behavior of a submerged entry nozzle for the casting of Ca-treated Al-killed Ti-bearing steel, Metall. Mater. Trans. B, 52(2021), No. 3, p. 1186. DOI: 10.1007/s11663-021-02110-z
|
| [8] |
H. Cui, Y.P. Bao, M. Wang, and W.S. Wu, Clogging behavior of submerged entry nozzles for Ti-bearing IF steel, Int. J. Miner. Metall. Mater., 17(2010), No. 2, p. 154. DOI: 10.1007/s12613-010-0206-y
|
| [9] |
S. Basu, S.K. Choudhary, and N.U. Girase, Nozzle clogging behaviour of Ti-bearing Al-killed ultra low carbon steel, ISIJ Int., 44(2004), No. 10, p. 1653. DOI: 10.2355/isijinternational.44.1653
|
| [10] |
L.J. Zhou, Z.H. Pan, W.L. Wang, et al., Interfacial interactions between inclusions comprising TiO2 or TiN and the mold flux during the casting of titanium-stabilized stainless steel, Metall. Mater. Trans. B, 51(2020), No. 1, p. 85. DOI: 10.1007/s11663-019-01746-2
|
| [11] |
Z.H. Pan, L.J. Zhou, and W.L. Wang, Study on the interaction process between mold flux and TiN/TiO2 by sessile drop method, [in] TMS 2020 149th Annual Meeting & Exhibition Supplemental Proceedings, The Minerals, Metals & Materials Series, Springer, Cham., 2020, p. 67.
|
| [12] |
W.L. Wang, D.X. Cai, L. Zhang, and I. Sohn, Effect of TiO2 and TiN on the viscosity, fluidity, and crystallization of fluorine-free mold fluxes for casting Ti-bearing steels, Steel Res. Int., 92(2021), No. 2, art. No. 2000314. DOI: 10.1002/srin.202000314
|
| [13] |
K.C. Mills, A.B. Fox, Z. Li, and R.P. Thackray, Performance and properties of mould fluxes, Ironmaking Steelmaking, 32(2005), No. 1, p. 26. DOI: 10.1179/174328105X15788
|
| [14] |
W.L. Wang, D.X. Cai, and L. Zhang, A review of fluorine-free mold flux development, ISIJ Int., 58(2018), No. 11, p. 1957. DOI: 10.2355/isijinternational.ISIJINT-2018-232
|
| [15] |
B. Ozturk, Solubility of TiN in continuous casting powders, Metall. Trans. B, 23(1992), No. 4, p. 523. DOI: 10.1007/BF02649671
|
| [16] |
E.B. Pretorius and R.C. Nunnington, Stainless steel slag fundamentals: From furnace to tundish, Ironmaking Steelmaking, 29(2002), No. 2, p. 133. DOI: 10.1179/030192302225003495
|
| [17] |
Z.S. Ren, X.J. Hu, X.M. Hou, X.X. Xue, and K.C. Chou, Dissolution and diffusion of TiO2 in the CaO–Al2O3–SiO2 slag, Int. J. Miner. Metall. Mater., 21(2014), No. 4, p. 345. DOI: 10.1007/s12613-014-0915-8
|
| [18] |
H. Park, J.Y. Park, G.H. Kim, and I. Sohn, Effect of TiO2 on the viscosity and slag structure in blast furnace type slags, Steel Res. Int., 83(2012), No. 2, p. 150. DOI: 10.1002/srin.201100249
|
| [19] |
L.F. Sun, H.P. Wang, M.F. Jiang, Q.Z. Lin, C.L. Liu, and Y. Zou, Effects of TiO2 on the viscocity and solidification temperature of mold fluxes for the stainless steel, Adv. Mater. Res., 189-193(2011), p. 107. DOI: 10.4028/www.scientific.net/AMR.189-193.107
|
| [20] |
R.C. Nunnington and N. Sutcliffe, The steelmaking and casting of Ti stabilized stainless steels, [in] 59th Electric Furnace Conference and 19th Process Technology Conference, Arizona, 2001, p. 361.
|
| [21] |
M. Hasegawa, S. Maruhashi, Y. Muranaka, and F. Hoshi, Mechanism of formation of surface defects in continuously cast stainless steel slabs containing titanium, Tetsu-to-Hagane, 73(1987), No. 3, p. 505. DOI: 10.2355/tetsutohagane1955.73.3_505
|
| [22] |
B.Y. Li, X. Geng, Z.H. Jiang, Y. Hou, and W. Gong, Effects of BaO and B2O3 on the absorption of Ti inclusions for high titanium steel, Metals, 11(2021), No. 1, art. No. 165. DOI: 10.3390/met11010165
|
| [23] |
Z.S. Bi, K.J. Li, C.H. Jiang, et al., Effects of B2O3 on the structure and properties of blast furnace slag by molecular dynamics simulation, J. Non-Cryst. Solids, 551(2021), art. No. 120412. DOI: 10.1016/j.jnoncrysol.2020.120412
|
| [24] |
F.F. Lai, W. Yao, and J.L. Li, Effect of B2O3 on structure of CaO–Al2O3–SiO2–TiO2–B2O3 glassy systems, ISIJ Int., 60(2020), No. 8, p. 1596. DOI: 10.2355/isijinternational.ISIJINT-2019-679
|
| [25] |
L.T. Bian and Y.H. Gao, Influence of B2O3 and basicity on viscosity and structure of medium titanium bearing blast furnace slag, J. Chem., 2016(2016), art. No. 6754593
|
| [26] |
Y.Q. Sun, J.L. Liao, K. Zheng, X.D. Wang, and Z.T. Zhang, Effect of B2O3 on the structure and viscous behavior of Ti-bearing blast furnace slags, JOM, 66(2014), No. 10, p. 2168. DOI: 10.1007/s11837-014-1087-8
|
| [27] |
L. Zhang and W.L. Wang, Growth mechanism and structure evolution during nucleation of calcium borosilicate crystal in CaO–SiO2–B2O3 based fluorine-free mold flux, ISIJ Int., 59(2019), No. 6, p. 1041. DOI: 10.2355/isijinternational.ISIJINT-2018-560
|
| [28] |
L. Zhang, W.L. Wang, and I. Sohn, Crystallization behavior and structure analysis for molten CaO–SiO2–B2O3 based fluorine-free mold fluxes, J. Non-Cryst. Solids, 511(2019), p. 41. DOI: 10.1016/j.jnoncrysol.2019.01.035
|
| [29] |
L. Zhang, W.L. Wang, B.Y. Zhai, and I. Sohn, The evolution of the mold flux melt structure during the process of fluorine replacement by B2O3, J. Am. Ceram. Soc., 103(2020), No. 1, p. 112. DOI: 10.1111/jace.16714
|
| [30] |
J.J. Zhang, B.Y. Zhai, L. Zhang, and W.L. Wang, A comparison study on interfacial properties of fluorine-bearing and fluorine-free mold flux for casting advanced high-strength steels, J. Iron Steel Res. Int., 29(2022), No. 10, p. 1613. DOI: 10.1007/s42243-021-00714-y
|
| [31] |
T.M. Yeo, J.W. Cho, M. Alloni, S. Casagrande, and R. Carli, Structure and its effect on viscosity of fluorine-free mold flux: Substituting CaF2 with B2O3 and Na2O, J. Non-Cryst. Solids, 529(2020), art. No. 119756. DOI: 10.1016/j.jnoncrysol.2019.119756
|
| [32] |
The Materials Project. Materials Data Materials Project for TiO2 (mp-2657) from Database Version v2021 [2022-10-28]. https://doi.org/10.17188/1184648
|
| [33] |
The Materials Project. Materials Data Materials Project for TiN (mp-492) from Database Version v2021 [2022-10-28]. https://doi.org/10.17188/1208488
|
| [34] |
X. Wu, S.X. Zhao, L. Wei, E.L. Zhao, J.W. Li, and C.W. Nan, Improved structural reversibility and cycling stability of Li2MnSiO4 cathode material by the pillar effect of [TiOx] polyanions, ChemistrySelect, 3(2018), No. 15, p. 4047. DOI: 10.1002/slct.201800036
|
| [35] |
S.Q. Jin, Z.D. Wang, G.J. Tao, et al., UV resonance Raman spectroscopic insight into titanium species and structure-performance relationship in boron-free Ti-MWW zeolite, J. Catal., 353(2017), p. 305. DOI: 10.1016/j.jcat.2017.07.032
|
| [36] |
Z. Wang, Q.F. Shu, and K. Chou, Structure of CaO–B2O3–SiO2–TiO2 glasses: A Raman spectral study, ISIJ Int., 51(2011), No. 7, p. 1021. DOI: 10.2355/isijinternational.51.1021
|
| [37] |
Z. Wang, Q.F. Shu, and K. Chou, Study on structure characteristics of B2O3 and TiO2-bearing F-free mold flux by Raman spectroscopy, High Temp. Mater. Processes, 32(2013), No. 3, p. 265. DOI: 10.1515/htmp-2012-0137
|
| [38] |
X.H. Zhang, Z. Du, H.T. Wu, and Y.L. Yue, Effect of TiO2 on structure and dielectric properties of RO–Al2O3–B2O3–SiO2 (R = Ca, Mg) glasses, Surf. Rev. Lett., 20(2013), No. 03n04, art. No. 1350030. DOI: 10.1142/S0218625X13500303
|
| [39] |
E. Kleebusch, C. Patzig, T. Hoeche, and C. Russel, The evidence of phase separation droplets in the crystallization process of a Li2O–Al2O3–SiO2 glass with TiO2 as nucleating agent – An X-ray diffraction and (S)TEM-study supported by EDX-analysis, Ceram. Int., 44(2018), No. 3, p. 2919. DOI: 10.1016/j.ceramint.2017.11.040
|
| [40] |
G.S. Back, M.J. Yoon, and W.G. Jung, Effect of the Cr2O3 and TiO2 as nucleating agents in SiO2–Al2O3–CaO–MgO glass-ceramic system, Met. Mater. Int., 23(2017), No. 4, p. 798. DOI: 10.1007/s12540-017-6714-9
|
| [41] |
Q. Wang, Y.J. Lu, S.P. He, K.C. Mills, and Z.S. Li, Formation of TiN and Ti(C,N) in TiO2 containing, fluoride free, mould fluxes at high temperature, Ironmaking Steelmaking, 38(2011), No. 4, p. 297. DOI: 10.1179/1743281210Y.0000000007
|
| [42] |
Y.H. Hua and B.J. Zhao, Phase equilibria in the system Al2O3–MnO–SiO2: Thermodynamic and application, [in] 11th International Symposium on High-Temperature Metallurgical Processing, California, 2020, p. 183.
|
| [43] |
M. Wittmer, J. Noser, and H. Melchior, Oxidation kinetics of TiN thin films, J. Appl. Phys., 52(1981), No. 11, p. 6659. DOI: 10.1063/1.328659
|
| [44] |
K. Kusabiraki, Infrared spectra of vitreous silica and sodium silicates containing titanium, J. Non-Cryst. Solids, 79(1986), No. 1-2, p. 208. DOI: 10.1016/0022-3093(86)90048-7
|
| [45] |
D. Yang, H.H. Zhou, J. Wang, et al., Influence of TiO2 on viscosity, phase composition and structure of chromium-containing high-titanium blast furnace slag, J. Mater. Res. Technol., 12(2021), p. 1615. DOI: 10.1016/j.jmrt.2021.03.069
|
| [46] |
K. Yan and D.F. Che, A coupled model for simulation of the gas–liquid two-phase flow with complex flow patterns, Int. J. Multiphase Flow, 36(2010), No. 4, p. 333. DOI: 10.1016/j.ijmultiphaseflow.2009.11.007
|
| [47] |
S.P. Gu, G.H. Wen, Z.Q. Ding, J.L. Guo, P. Tang, and Q. Liu, Effect of bubbles on crystallization behavior of CaO–SiO2 based slags, Metals, 9(2019), No. 2, art. No. 193. DOI: 10.3390/met9020193
|
| [1] | Jian-xun Fu, Jing-she Li, Hui Zhang. Effects of the width and thickness of slabs on broadening in continuous casting [J]. International Journal of Minerals, Metallurgy and Materials, 2010, 17(6): 723-728. DOI: 10.1007/s12613-010-0380-y |
| [2] | A. Ramírez-López, G. Soto-Cortés, M. Palomar-Pardavé, M. A. Romero-Romo, R. Aguilar-López. Computational algorithms to simulate the steel continuous casting [J]. International Journal of Minerals, Metallurgy and Materials, 2010, 17(5): 596-607. DOI: 10.1007/s12613-010-0362-0 |
| [3] | A. Ramírez-López, R. Aguilar-López, A. Kunold-Bello, J. González-Trejo, M. Palomar-Pardavé. Simulation factors of steel continuous casting [J]. International Journal of Minerals, Metallurgy and Materials, 2010, 17(3): 267-275. DOI: 10.1007/s12613-010-0304-x |
| [4] | Di-feng Wu, Shu-sen Cheng, Zi-jian Cheng. Characteristics of shell thickness in a slab continuous casting mold [J]. International Journal of Minerals, Metallurgy and Materials, 2009, 16(1): 25-31. DOI: 10.1016/S1674-4799(09)60005-4 |
| [5] | Fangming Yuan, Xinghua Wang, Jiongming Zhang, Li Zhang. Numerical simulation of Al203 deposition at a nozzle during continuous casting [J]. International Journal of Minerals, Metallurgy and Materials, 2008, 15(3): 227-235. DOI: 10.1016/S1005-8850(08)60043-2 |
| [6] | Qiaotong Lu, Rongguang Yang, Xinhua Wang, Jiongming Zhang, Wanjun Wang. Water modeling of mold powder entrapment in slab continuous casting mold [J]. International Journal of Minerals, Metallurgy and Materials, 2007, 14(5): 399-404. DOI: 10.1016/S1005-8850(07)60079-6 |
| [7] | Mingzhong Liu, Jingshe Li, Shiqi Li, Hongjun Yan, Yingjun Fan, Mingsheng Yang. Application of soft reduction technique to continuous-casting billets [J]. International Journal of Minerals, Metallurgy and Materials, 2004, 11(4): 302-305. |
| [8] | Kaitao Bo, Guoguang Cheng, Jie Wu, Pei Zhao, Jun Wang. Mechanism of Oscillation Mark Formation in Continuous Casting of Steel [J]. International Journal of Minerals, Metallurgy and Materials, 2000, 7(3): 189-192. |
| [9] | Jiying Li, Chuanji Han, Kaike Cai, Subo Yang, Xuemo Yan. Water Model Study of Level Flunction in Continuous Casting Mold [J]. International Journal of Minerals, Metallurgy and Materials, 1998, 5(3): 155-155. |
| [10] | SUN Shaoyuan, LI Shiping, WANG Junran. Intelligent Control Method for the Secondary Cooling of Continuous Casting [J]. International Journal of Minerals, Metallurgy and Materials, 1997, 4(2): 46-46. |
| 1. | Zhuo Chen, Binqi Yu, Tingfeng Yao, et al. Wetting and Reaction Behavior of TiN and TiO2 with Different Mold Fluxes for High Ti-Bearing Stainless Steel. Metallurgical and Materials Transactions B, 2025, 56(1): 20. DOI:10.1007/s11663-024-03334-5 |
| 2. | Qiang Liu, Xiang Li, Shen Du, et al. Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope. International Journal of Minerals, Metallurgy and Materials, 2025, 32(1): 102. DOI:10.1007/s12613-024-2896-6 |
| 3. | Rongzhen Mo, Hejun Zhang, Ying Ren, et al. Multicomponent Mixed-Transport-Control Kinetic and Thermodynamic Model for the Reaction Between High-Aluminum Steel and Mold Flux with Varied Al2O3/SiO2 Ratios: Experimental Result and Theoretical Model. Metallurgical and Materials Transactions B, 2025. DOI:10.1007/s11663-025-03473-3 |
| 4. | Rong-zhen Mo, Ying Ren, Li-feng Zhang. Kinetic and thermodynamic calculations of reaction involving high aluminum low manganese steels and medium SiO2 medium Al2O3 mold fluxes with different initial aluminum contents. Journal of Iron and Steel Research International, 2025. DOI:10.1007/s42243-025-01459-8 |
| 5. | Jiyu Qiu, Wenjie Li, Chengjun Liu, et al. Phase equilibria in the CaO‒Al2O3‒TiN system and CaO‒Al2O3‒Ti2O3‒TiN system at 1500°C. Journal of the American Ceramic Society, 2025. DOI:10.1111/jace.20403 |
| 6. | Yu-die Gu, Ying Ren, Li-feng Zhang. In-situ observation on dissolution of CaO–SiO2–Al2O3 complex inclusions in refining slag. Journal of Iron and Steel Research International, 2025, 32(2): 376. DOI:10.1007/s42243-024-01405-0 |
| 7. | Ruijing Sun, Jinhu Wu, Hui Wang, et al. Reaction mechanism between carbon and CaO–SiO2–Al2O3–Na2O slag system during continuous casting process. Journal of Materials Research and Technology, 2024, 30: 8882. DOI:10.1016/j.jmrt.2024.05.242 |
| 8. | Haixin Yang, Ying Ren, Jinshu Wang, et al. <i>In-situ</i> Observation of Precipitation and Growth of MnS Inclusions during Solidification of a High Sulfur Steel. ISIJ International, 2024, 64(14): 2020. DOI:10.2355/isijinternational.ISIJINT-2024-195 |
| 9. | Jinlong Wang, Zhengliang Xue, Shengqiang Song. Investigation of the Dissolution Behavior of AlN in CaO–Al2O3–MgO Refining Slag and CaO–Al2O3–F–Li2O–BaO Mold Flux. steel research international, 2024. DOI:10.1002/srin.202400583 |
| 10. | Li Zhang, Wanlin Wang, Lei Zhang, et al. Characterization of Minerals, Metals, and Materials 2024. The Minerals, Metals & Materials Series, DOI:10.1007/978-3-031-50304-7_15 |
Figures(9) / Tables(1)
Copyright©2019 Editorial Office of International Journal of Minerals, Metallurgy and Materials 京ICP备13030111号
Supported by:
Beijing Renhe Information Technology Co., Ltd.
Email:
info@rhhz.net
| CaO/SiO2 mass ratio | Content / wt% | ||||
| CaO | SiO2 | Al2O3 | Na2O | B2O3 | |
| 1.0 | 37.5 | 37.5 | 5 | 10 | 6 |
DownLoad:
CSV
Search
