Preparation of glass-ceramics using TiO2 composite chromium-iron alloy sintering slag and its process

Abstract

The present invention discloses a glass-ceramic prepared using TiO2 composited with ferrochrome sintered slag and a process for preparing the same. The raw materials include the following components by mass percentage: 63-69.5% ferrochrome sintered slag, 18-22% SiO2, 9.5-10.5% TiO2, 1.6-3% MgO, 1-2% Al2O3, and 0.05-1% FeO. The ferrochrome sintered slag includes the following components by mass percentage: 37-41.5% CaO, 27-33.5% SiO2, 6.5-10% MgO, 6.5-9% Al2O3, 5-7.5% Fe2O3, 2.5-4% Cr2O3, 2-2.5% FeO, 1.5-2.5% Na2O, and 1-1.6% BaO. The glass-ceramic produced by the present invention has excellent physical and chemical properties.

Description

Technical Field

[0001] The present invention relates to the technical field of microcrystalline glass, and in particular to a microcrystalline glass prepared by utilizing TiO2 composite chromium-iron alloy sintering slag and a process thereof. Background Art

[0002] With the rapid development of my country's economy and the continuous improvement of people's living standards, the demand for various materials is also increasing. The irregular arrangement of atoms within ordinary glass makes it fragile. However, glass-ceramics is made by subjecting the glass to a specific heat treatment, which creates a uniform crystalline phase within it. This makes it brighter than ceramics and stronger than glass, combining the advantages of both, possessing the dual characteristics of glass and ceramics. The diverse composition, structure, and properties of glass-ceramics have led to their application in a wide range of fields, including architecture, military industry, and biological sciences, and the performance of glass-ceramics continues to expand.

[0003] With the rapid increase in stainless steel production in recent years, the demand for ferrochrome has also increased. However, this has also brought inevitable problems, such as high energy consumption during production and the massive accumulation of solid waste, which has seriously impacted the natural environment, human life, and health. Solid waste primarily refers to slag, over 80% of which is steel slag and blast furnace slag. Furthermore, chromium is a heavy metal element that can cause certain environmental pollution. Therefore, finding a rational and comprehensive method to utilize ferrochrome alloy sintering slag is of great significance for resource utilization, energy conservation and emission reduction, and environmental protection.

[0004] Low-carbon ferrochrome sinter slag is a metallurgical waste residue produced during the high-temperature reduction of chromite at 1700°C using carbon as a reducing agent to produce ferrochrome. The main components of low-carbon ferrochrome sinter slag are CaO, SiO2, Al2O3, and MgO, with small amounts of Cr2O3 and Fe2O3. Architectural decorative glass-ceramics produced from industrial solid waste generally belong to the CaO-SiO2-Al2O3 or CaO-SiO2-MgO-Al2O3 system. Furthermore, the Fe2O3, Cr2O3, and high-melting-point substances in the ferrochrome sinter slag create conditions for heterogeneous nucleation, playing a positive role in the production of glass-ceramics. Therefore, using ferrochrome sinter slag to produce glass-ceramics can significantly increase the added value of ferrochrome sinter slag, while saving costs and protecting the environment. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: to overcome the shortcomings of the existing technology and provide a microcrystalline glass and process prepared by using TiO2 composite chromium-iron alloy sintering slag. By rationally designing the microcrystalline glass components and adding TiO2 as the crystal growth core, and combining a new sintering method, the sintering process occurs before crystallization, so that the finally produced microcrystalline glass has excellent physical and chemical properties.

[0006] The technical solution of the present invention is:

[0007] On the one hand, the present invention provides a microcrystalline glass prepared by using TiO2 composite ferrochromium alloy sintered slag, the raw materials including the following components in mass percentage: ferrochromium alloy sintered slag 63-69.5%, SiO2 18-22%, TiO2 9.5-10.5%, MgO 1.6-3%, Al2O3 1-2%, FeO 0.05-1%; wherein, the ferrochromium alloy sintered slag includes the following components in mass percentage: CaO 37-41.5%, SiO2 27-33.5%, MgO 6.5-10%, Al2O3 6.5-9%, Fe2O3 5-7.5%, Cr2O3 2.5-4%, FeO 2-2.5%, Na2O 1.5-2.5%, BaO 1-1.6%.

[0008] Preferably, the raw materials include the following components in mass percentage: 66.08% of ferrochrome sintered slag, 20.27% of SiO2, 10.16% of TiO2, 2.11% of MgO, 1.31% of Al2O3, and 0.07% of FeO; wherein, the ferrochrome sintered slag includes the following components in mass percentage: 39.17% of CaO, 30.24% of SiO2, 8.01% of MgO, 7.62% of Al2O3, 6.21% of Fe2O3, 3.24% of Cr2O3, 2.22% of FeO, 2.02% of Na2O, and 1.27% of BaO.

[0009] On the other hand, the present invention also provides a preparation process for the microcrystalline glass prepared by using the TiO2 composite chromium-iron alloy sintered slag. The chromium-iron alloy sintered slag is ball-milled into uniform fine particles in a ball mill, weighed together with other components and prepared into a mixture. The mixture is ground in a ball mill, and after being fully mixed and evenly mixed, it is placed in a corundum crucible, and then placed in a high-temperature lifting furnace for melting and insulation. After cooling, it is crystallized to make the glass melt homogenized and refined to obtain clear and uniform glass liquid; the glass liquid is poured into a mold, and after forming and demolding, the block glass is sent to an electric furnace for insulation annealing to eliminate internal stress, and then cooled to room temperature with the furnace to obtain basic glass, and microcrystalline glass is obtained after cutting.

[0010] Preferably, the particle size of the ferrochrome alloy sintered slag after ball milling is 1.5-1.8 mm.

[0011] Preferably, after the mixed material is placed in a high-temperature lifting furnace, the temperature is increased to 1600-1640° C. at a heating rate of 45-55° C. / min to melt and the temperature is kept for 35-45 minutes.

[0012] Preferably, after the mixed material is placed in a high-temperature lifting furnace, the temperature is increased to 1620° C. at a heating rate of 50° C. / min to melt and the temperature is kept at this temperature for 40 minutes.

[0013] Preferably, the temperature is lowered to 925-975° C. at a cooling rate of 5-10° C. / min, and crystallization is performed for 55-65 min.

[0014] Preferably, the temperature is lowered to 950° C. at a cooling rate of 10° C. / min, and crystallization is performed for 60 minutes.

[0015] Preferably, the temperature in the electric furnace is 525-575° C., and the annealing is carried out for 4-5 hours.

[0016] Preferably, the temperature in the electric furnace is 550° C., and the annealing is carried out for 4.5 hours.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention rationally designs the components of the microcrystalline glass and adds TiO2 as the crystal growth core, and combines a new sintering method. The sintering process occurs before crystallization, so that the microcrystalline glass finally produced has excellent physical and chemical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is the XRD spectrum of the ferrochrome alloy sintered slag of the present invention.

[0020] Figure 2 This is an SEM image of the glass-ceramics prepared in Example 3 of the present invention.

[0021] Figure 3 This is the EDS spectrum of the glass-ceramics prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below.

[0023] The raw materials of the ferrochrome sintered slag in the following embodiments are water-quenched in the actual production of the steel plant, and the remaining raw materials are all chemically pure raw materials. Among them, the main components of the ferrochrome sintered slag are CaO, MgO, SiO2, and Al2O3, and the content is relatively high. Among them, SiO2 is the main oxide that constitutes the glass skeleton, and CaO, Al2O3, MgO, etc. can act as network modifiers or network exogenous bodies in the glass, and can play a role in regulating the various properties of the glass. Therefore, in order to improve the utilization rate of the ferrochrome sintered slag, the microcrystalline glass is determined to be a CaO-Al2O3-MgO-SiO2 system. In addition, Fe2O3 and Cr2O3 in the ferrochrome sintered slag are effective nucleating agents for the system, creating favorable conditions for heterogeneous nucleation, which is beneficial to the preparation of microcrystalline glass.

[0024] The type and quantity of the main crystal phase of glass-ceramics determine the physical and chemical properties and performance of glass-ceramics. The chromium-iron alloy sintered slag is subjected to X-ray diffraction analysis (XRD), and the XRD pattern is as follows: Figure 1 It can be found that the main crystal phases of the ferrochrome alloy sintered slag selected in the present invention are magnesia siliceous stone (Ca3MgSi2O8) and wollastonite (CaSiO3), which has stable structure and chemical properties and excellent mechanical properties, and can meet the requirements of microcrystalline glass as a building material.

[0025] Using ferrochrome alloy sintered slag, MgO, SiO2, Al2O3, TiO2 and FeO as raw materials, basic glass is prepared by high-temperature melting method, and microcrystalline glass is obtained after heat treatment. Specifically, the chromium-iron alloy sintered slag is first ball-milled in a ball mill to obtain uniform fine particles (average particle size 1.5-1.8mm), the required raw materials are accurately weighed and the prepared mixture is ground and mixed in a ball mill jar. After being fully mixed, it is placed in a corundum crucible and placed in a high-temperature lifting furnace. The temperature is increased to 1600-1640℃ at a heating rate of 45-55℃ / min and melted and kept warm for 35-45min. The temperature is then reduced to 925-975℃ at a cooling rate of 5-10℃ / min and crystallized for 55-65min to homogenize and refine the glass melt to obtain clear and uniform glass liquid; the glass liquid is poured into a mold, and after forming and demolding, the block glass is quickly sent to an electric furnace at a temperature of 525-575℃ for annealing for 4-5h to eliminate internal stress, and then cooled to room temperature with the furnace to obtain basic glass, and microcrystalline glass is obtained after cutting.

[0026] Examples 1-5

[0027] The composition of the ferrochrome alloy sintered slag was analyzed by X-ray fluorescence spectrometry, and the composition of the ferrochrome alloy sintered slag of Examples 1-5 was measured as shown in Table 1:

[0028] Table 1 Composition of ferrochrome alloy sintered slag in Examples 1-5 (wt.%)

[0029]

[0030] The raw material compositions of the glass-ceramics in Examples 1-5 are shown in Table 2:

[0031] Table 2 Raw material composition of glass-ceramics in Examples 1-5 (wt.%)

[0032]

[0033] During the preparation of the glass-ceramics of Examples 1-5, the process parameters are shown in Table 3:

[0034] Table 3 Preparation process parameters of glass-ceramics of Examples 1-5

[0035]

[0036] like Figure 2-3 As shown, the glass-ceramics prepared by the present invention is a composite system glass-ceramics containing iron-containing diopside and spinel subcrystalline phases (pyroxene-nepheline composite system glass-ceramics). The spinel phase is formed during the nucleation process due to the reaction of Cr2O3 in the chromium-iron alloy sintering slag with substances such as MgO and Fe2O3, which enriches and produces element-inhomogeneous areas to form spinel. It serves as the heterogeneous nucleation core of the diopside phase. After the addition of chromium-iron alloy sintering slag is increased, the generated spinel is not completely consumed and converted into the diopside phase, so the spinel phase diffraction peak appears in the finished glass-ceramics.

[0037] The SEM image and EDS spectrum of the glass-ceramics prepared in Example 3 are as follows: Figure 2-3 As shown by Figure 2 It can be seen that TiO2 not only participates in the crystallization of glass-ceramics, but also forms solid solutions with other elements to promote the formation of new phases. TiO2 and Fe2O3 act as crystal nuclei, which is related to the existence state of oxides. 3+ and Fe 2+ There are two forms, Fe 3+ It will increase the viscosity of the glass, thereby inhibiting the crystallization of the glass system. 2+ It is beneficial to the crystallization of the glass system. 4+ and Ti 2+ exists in the form of Ti 4+ and Ti 2+ All of them are conducive to promoting crystallization. Combined with EDS energy spectrum, it can be clearly seen that TiO2 aggregates together, promoting the phase separation and crystallization of the glass, while Fe2O3 is only partially aggregated together, and may form an iron-containing pyroxene crystal phase with other elements, so that the final microcrystalline glass has extremely good flexural strength, low water absorption, high hardness and acid and alkali resistance, and has good application prospects.

[0038] Comparative Examples 1-5

[0039] The difference between Comparative Examples 1-5 and Example 3 is that the components of the ferrochrome alloy sintered slag are different from those in Example 1. The components of the ferrochrome alloy sintered slag in Comparative Examples 1-5 are shown in Table 4:

[0040] Table 4 Composition of ferrochrome alloy sintered slag in Comparative Examples 1-5 (wt.%)

[0041]

[0042] The physical and chemical properties of the finished glass-ceramics prepared in Examples 1-5 and Comparative Examples 1-5 were tested, and the test results are shown in Table 5:

[0043] Table 5 Physical and chemical properties test results of finished glass-ceramics prepared in Examples 1-5 and Comparative Examples 1-5

[0044]

[0045] Compared with Example 3, the mechanical properties of the microcrystalline glass prepared in Comparative Example 1 are reduced. This is because the sintered slag used therein lacks Fe2O3, which is not conducive to better bonding with TiO2, thereby resulting in a reduction in the mechanical properties of the microcrystalline glass.

[0046] Compared with Example 3, the chemical properties (acid resistance and alkali resistance) of the microcrystalline glass prepared in Comparative Example 2 are reduced. This is because the sintering slag used therein lacks Cr2O3. Cr2O3 will form a composite nucleating agent with Fe2O3, which can effectively promote the crystallization of microcrystalline glass, accelerate the crystallization of glass, enhance the chemical properties of glass, and make the glass structure more stable.

[0047] Compared with Example 3, the density and glossiness of the glass-ceramics prepared in Comparative Example 3 are reduced. This is because the sintered slag used therein lacks BaO. Proper addition of BaO can improve the material properties of the glass, accelerate the melting of the glass, and thus improve the damage resistance of the glass. 2+ The smaller the radius, the easier it is to enter the glass network structure. Due to its high electronegativity, it has a strong attraction to the surrounding molecules, which increases the strength and thus affects the gloss of the glass.

[0048] Compared with Example 3, the glossiness of the glass-ceramics prepared in Comparative Example 4 is reduced. This is because the iron-manganese alloy sintered slag contains relatively high iron and manganese elements, which can be used as the raw material of glass-ceramics. The raw material of the present invention contains MgO and TiO2, the basic components are relatively high in alkalinity, and Mn 3+ The darker the color of the ions, the faster they absorb the visible spectrum, making the glass dark brown and affecting the gloss of the glass.

[0049] Compared with Example 3, the glossiness of the glass-ceramics prepared in Comparative Example 5 is reduced. This is because the MgO content in the metallurgical waste slag is low, and the low MgO content will lead to the 2+ Al in blocking glass 3+ Diffusion to the glass surface reduces the movement of ions, inhibits the surface activity of the glass, and reduces the gloss of the glass.

[0050] Comparative Examples 6-8

[0051] The difference between Comparative Examples 6-8 and Example 3 is that the components of the glass-ceramics in Comparative Examples 6-8 are shown in Table 6:

[0052] Table 6 Composition of glass-ceramics in Comparative Examples 6-8 (wt.%)

[0053]

[0054] The physical and chemical properties of the finished glass-ceramics prepared in Comparative Examples 6-8 were tested, and the test results are shown in Table 7:

[0055] Table 7 Physical and chemical properties test results of finished glass-ceramics prepared in Comparative Examples 6-8

[0056]

[0057] Compared with Example 3, the mechanical properties (flexural strength, Vickers hardness), density and glossiness of the microcrystalline glass prepared in Comparative Examples 6-8 decreased. This is because with the increase of TiO2 content, the flexural strength of the microcrystalline glass tends to increase. This is because TiO2 is a high-field strength oxide, which can make the structure of the glass dense and promote the crystallization of the glass. The main reason why the Vickers hardness and density first increase and then decrease is that TiO2 makes the glass highly crystallized and the grains evenly distributed. The precipitated grains are spherical, the crystal morphology is well developed, and there are fewer glass phases, so the hardness is high; but if the TiO2 content is too high, it will inhibit the crystallization tendency and reduce the crystal crystallization strength. The main reason why the glass glossiness first increases and then decreases is that TiO2 4+ Ions can strongly absorb ultraviolet rays, and the absorption band enters the blue-violet part of the visible light region, making the glass transparent and increasing the gloss of the glass; excessive TiO2 will make Ti 4+ The ions absorb a lot of ultraviolet light, and the absorption band enters the near-infrared region, making the glass look yellow and reducing the gloss of the glass.

[0058] Comparative Examples 9-11

[0059] The difference from Example 3 is that the comparative examples 9-11 were heated to 1620°C at heating rates of 30°C / min, 40°C / min, and 60°C / min, respectively, and melted and kept warm for 40 minutes.

[0060] Comparative Example 12

[0061] The difference from Example 3 is that in a high-temperature lifting furnace, crystallization is first performed at 950° C. at a heating rate of 10° C. / min for 60 min, and then sintering is performed at 1620° C. at a heating rate of 50° C. / min for 40 min.

[0062] The physical and chemical properties of the glass-ceramics prepared in Comparative Examples 9-12 were tested, and the test results are shown in Table 8:

[0063] Table 8 Physical and chemical properties test results of glass-ceramics prepared in Comparative Examples 9-12

[0064]

[0065] Compared with Example 3, the physical and chemical properties of the microcrystalline glass prepared in Comparative Examples 9-11 have declined. This is because the crystallization temperature is lower than the sintering temperature. Therefore, if the temperature rises too slowly in the early stage, crystallization has already begun, which will affect the sintering process and ultimately affect the performance of the glass.

[0066] Compared with Example 3, the physical and chemical properties of the microcrystalline glass prepared in Comparative Example 12 also decreased, because its crystallization process occurs before the sintering process. During the high-temperature sintering process of microcrystalline glass, there are sintering and crystallization processes at the same time, and the two are carried out simultaneously and compete with each other. The crystallization process will cause the viscosity of the glass to increase and the atomic mobility to decrease, which will hinder the sintering of the glass powder and thus affect the performance of the material. Therefore, the sintering process is best to occur before the crystallization process. However, due to the TiO2, Cr2O3 and Fe2O3 contained in the chromium-iron alloy sintering slag, it is conducive to the improvement of crystallization, making the microcrystalline glass crystallization strong and fast, resulting in the crystallization temperature being lower than the sintering temperature, which is not conducive to the sintering of the microcrystalline glass, thereby affecting the performance of the glass. Therefore, in view of the characteristics of ferrochrome alloy sintering slag, which has a high sintering temperature, strong crystallization ability, and a crystallization temperature lower than the sintering temperature, the present invention proposes a new sintering method: first, by increasing the heating rate, it is difficult for the precipitated crystal nuclei to grow fully, thereby inhibiting the crystallization effect and precipitating a certain number of crystal nuclei; when the temperature reaches the sintering temperature, sintering between the basic glass particles gradually begins, producing a certain amount of liquid phase, and nucleation is achieved at this temperature, and the basic glass particles are sintered into shape; then the temperature is lowered to the crystallization temperature to achieve glass crystallization, thereby preparing micro-ceramics with good performance.

[0067] Comparative Examples 13-16

[0068] The difference between Comparative Examples 13-16 and Example 3 is that the sintering temperatures are shown in Table 9. In addition, the flexural strength of the glass-ceramics prepared in Example 3, Example 5 and Comparative Examples 13-16 was tested, and the test results are shown in Table 9.

[0069] Table 9 Sintering temperature and flexural strength test results of glass-ceramics of Example 3, Example 5 and Comparative Examples 13-16

[0070]

[0071] As can be seen from Table 9, due to the characteristics of high sintering temperature, strong crystallization ability and crystallization temperature lower than the sintering temperature of ferrochrome alloy sintering slag, when the sintering temperature is low, the precipitated crystal phase will hinder the sintering effect between particles, which is not conducive to the removal of pores between particles, affecting the density of the sample and causing a decrease in flexural strength; while too high a sintering temperature will cause bulging or even deformation of the surface between particles. In order to fully melt the basic glass raw materials, the melting temperature should be controlled above 1350°C to ensure complete melting of the raw materials. When the sintering temperature is higher than 1640°C, the sample deforms and melts, cracks appear, and the flexural strength cannot be measured. Therefore, the sintering temperature of 1620°C in Example 3 is the optimal sintering temperature.

[0072] The physical and chemical properties of the glass-ceramics prepared in Example 3, Example 5, and Comparative Examples 13-15 were tested, and the test results are shown in Table 10:

[0073] Table 10 Test results of physical and chemical properties of glass-ceramics prepared in Example 3, Example 5, and Comparative Examples 13-15

[0074]

[0075] It can be seen from Table 10 that the flexural strength and Vickers hardness of the microcrystalline glass prepared in Comparative Examples 13-15 have decreased, while other physical and chemical properties have not changed much. This shows that if the sintering temperature is too high or too low, the metal oxides (such as magnesium oxide and iron oxide) in the glass formula will not be able to play their role well, forming variable valence metals, thereby resulting in performance degradation.

[0076] Comparative Examples 17-21

[0077] The difference between Comparative Examples 17-21 and Example 3 is that the sintering time is shown in Table 11. In addition, the flexural strength of the glass-ceramics prepared in Example 3 and Comparative Examples 17-21 was tested, and the test results are shown in Table 11.

[0078] Table 11 Sintering time and flexural strength test results of glass-ceramics of Example 3 and Comparative Examples 17-21

[0079] Comparative Example 17 Comparative Example 18 Comparative Example 19 Example 3 Comparative Example 20 Comparative Example 21 Sintering time (min) 10 20 30 40 50 60 Flexural strength (MPa) 42.2 55.8 58.3 87.45 75.5 64.4

[0080] As shown in Table 11, sintering times that are too short or too long are not conducive to improving the flexural strength of glass-ceramics. Therefore, while ensuring sintering quality, the sintering time should be shortened as much as possible. This can shorten production time, reduce equipment energy consumption, and lower production costs. However, if the sintering time is too short, the amount of liquid phase generated between the sintered particles will be insufficient, resulting in lower flexural strength. If the sintering time is too long, grain growth and recrystallization will affect the sintering density of the material, resulting in a decrease in flexural strength. Therefore, the optimal sintering time is 40 minutes as in Example 3.

[0081] The physical and chemical properties of the glass-ceramics prepared in Example 3 and Comparative Examples 17-21 were tested. The test results are shown in Table 12:

[0082] Table 12 Physical and chemical properties test results of glass-ceramics prepared in Example 3 and Comparative Examples 17-21

[0083]

[0084] It can be seen from Tables 11-12 that a sintering time that is too short or too long will reduce the Vickers hardness. This is because if the sintering time is too short, the Fe2O3 and Cr2O3 nucleation agents in the chromium-iron alloy sintering slag in the glass cannot react completely, the crystallization tendency is not obvious, and the glass hardness is reduced; if the sintering time is too long, the excessive growth of the grains and the recrystallization ability will affect the compactness of the glass structure, resulting in a decrease in Vickers hardness.

[0085] Comparative Examples 22-27

[0086] The difference between Comparative Examples 22-27 and Example 3 is that the crystallization time is shown in Table 13. In addition, the flexural strength of the glass-ceramics prepared in Example 3 and Comparative Examples 22-27 was tested, and the test results are shown in Table 13.

[0087] Table 13 Crystallization time and flexural strength test results of glass-ceramics of Example 3 and Comparative Examples 22-27

[0088] Comparative Example 22 Comparative Example 23 Comparative Example 24 Comparative Example 25 Example 3 Comparative Example 26 Comparative Example 27 Crystallization time (min) 10 20 30 40 60 70 80 Flexural strength (MPa) 45.7 53.89 70.2 77.45 88.5 66.9 56.4

[0089] Table 13 shows that crystal formation occurs in two stages: nucleation and growth. When the crystallization time is insufficient, the grains are underdeveloped, resulting in a large amount of glass phase in the glass-ceramics, which leads to lower flexural strength. As the crystallization time increases, the grains can fully grow, which is beneficial to improving the flexural strength of the glass-ceramics. However, if the crystallization time is too long, the grains continue to grow, which is not conducive to the fine grain strengthening effect, thereby reducing the flexural strength of the glass-ceramics. Therefore, the optimal crystallization time is 60 minutes.

[0090] The physical and chemical properties of the glass-ceramics prepared in Example 3 and Comparative Examples 22-27 were tested. The test results are shown in Table 14:

[0091] Table 14 Test results of physical and chemical properties of glass-ceramics prepared in Example 3 and Comparative Examples 22-27

[0092]

[0093] It can be seen from Table 14 that when the crystallization time is insufficient, the grains are not fully developed, which is not conducive to obtaining large crystal nuclei and the density decreases; as the crystallization time increases, Cr2O3 in the chromium-iron alloy sintering slag reacts with MgO, Fe2O3 and other substances, allowing the grains to grow fully, which is beneficial to the improvement of the performance of the microcrystalline glass; but if the crystallization time is too long, the grains continue to grow, the density increases, and the performance of the microcrystalline glass decreases.

Claims

1. A process for preparing glass-ceramics by using TiO2 composite chromium-iron alloy sintered slag, characterized in that: The glass-ceramic raw material includes the following components in mass percentage: 63-69.5% of ferrochrome sintered slag, 18-22% of SiO2, 9.5-10.5% of TiO2, 1.6-3% of MgO, 1-2% of Al2O3, and 0.05-1% of FeO; wherein the ferrochrome sintered slag includes the following components in mass percentage: 37-41.5% of CaO, 27-33.5% of SiO2, 6.5-10% of MgO, 6.5-9% of Al2O3, 5-7.5% of Fe2O3, 2.5-4% of Cr2O3, 2-2.5% of FeO, 1.5-2.5% of Na2O, and 1-1.6% of BaO; The preparation process of microcrystalline glass is as follows: ball-milling the chromium-iron alloy sintered slag into uniform fine particles, weighing it together with other components and preparing a mixture, grinding the mixture, mixing it thoroughly and evenly, and placing it in a corundum crucible, then placing it in a high-temperature lifting furnace, heating it to 1600-1640℃ at a heating rate of 45-55℃ / min, melting it and keeping it warm for 35-45min; then cooling it to 925-975℃ at a cooling rate of 5-10℃ / min, crystallizing it for 55-65min to obtain clear and uniform glass liquid; pouring the glass liquid into a mold, and after forming and demolding, sending the block glass to an electric furnace for insulation annealing to eliminate internal stress, and then cooling it to room temperature with the furnace to obtain basic glass, and microcrystalline glass is obtained after cutting.

2. The process for preparing glass-ceramics by using TiO2 composite chromium-iron alloy sintered slag as claimed in claim 1, characterized in that: The raw materials include the following components in mass percentage: 66.08% of ferrochrome alloy sintered slag, 20.27% of SiO2, 10.16% of TiO2, 2.11% of MgO, 1.31% of Al2O3, and 0.07% of FeO; wherein, the ferrochrome alloy sintered slag includes the following components in mass percentage: 39.17% of CaO, 30.24% of SiO2, 8.01% of MgO, 7.62% of Al2O3, 6.21% of Fe2O3, 3.24% of Cr2O3, 2.22% of FeO, 2.02% of Na2O, and 1.27% of BaO.

3. The process for preparing glass-ceramics by using TiO2 composite chromium-iron alloy sintering slag as claimed in claim 1, characterized in that: The particle size of the ferrochrome alloy sintered slag after ball milling is 1.5-1.8 mm.

4. The process for preparing glass-ceramics by using TiO2 composite chromium-iron alloy sintered slag as claimed in claim 1, characterized in that: After the mixture is placed in a high-temperature lifting furnace, it is heated to 1620°C at a heating rate of 50°C / min and melted and kept warm for 40 minutes.

5. The process for preparing glass-ceramics by using TiO2 composite chromium-iron alloy sintered slag as claimed in claim 1, characterized in that: The temperature was lowered to 950°C at a cooling rate of 10°C / min and crystallized for 60 min.

6. The process for preparing glass-ceramics by using TiO2 composite chromium-iron alloy sintered slag as claimed in claim 1, characterized in that: The temperature in the electric furnace is 525-575℃, and the annealing is carried out for 4-5 hours.

7. The process for preparing glass-ceramics by using TiO2 composite chromium-iron alloy sintered slag as claimed in claim 1, characterized in that: The temperature in the electric furnace is 550°C, and the annealing is carried out for 4.5 hours.

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