A method for improving the strength and modulus of continuous basalt fiber by multi-component compounding of raw materials

Abstract

The present application belongs to the field of inorganic non-metallic materials, and particularly relates to a method for improving the strength and modulus of continuous basalt fiber by multi-component mixing of raw materials. The present application adjusts the mass percentage content of raw material minerals and main oxides, i.e. the mass percentage content of network formers, network intermediates and network modifiers, by mixing different fibers with basalt raw materials. Without changing the "naturalness" and "environmental protection" advantages of continuous basalt fiber, the present application adds appropriate amount of reinforcing and modulus-increasing oxides with high bond strength and no environmental hazards to enhance the integrity of the network structure, and introduces trace amount of atmosphere (oxidation or reduction) adjuster to precisely control the ratio of FeO / (Fe2O3+FeO) in the mixture, so that the homogeneity and thermal conductivity of the glass liquid in the fiber drawing process are greatly improved, so as to more accurately control the heat penetration and homogeneity of the molten liquid, and under the premise of ensuring continuous and stable industrial production, the strength and modulus of the continuous basalt fiber precursor are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of inorganic non-metallic materials, and particularly relates to a method for improving the strength and modulus of continuous basalt fiber by multi-element mixing of raw materials. BACKGROUND

[0002] Continuous basalt fiber is an ore fiber made of basic-neutral magmatic rock ores such as basalt, diabase, gabbro, basaltic andesite, diabase, and pyroxene diorite, etc. through a melting-drawing process, with the mineral and chemical composition content of the ores being within a suitable range. The continuous basalt fiber has excellent performance in mechanics, dielectric, heat resistance, alkali corrosion resistance, etc., and the production process is environmentally friendly, and is known as a new green inorganic fiber material in the 21st century.

[0003] Generally, a specific ore has its specific mineral composition and chemical composition content, which plays a major role in determining the performance of the prepared fiber, including strength and modulus. Compared with glass fiber, it is difficult to continuously and stably form continuous basalt fiber, the dispersion coefficient is high, and the performance of the product such as strength and modulus is difficult to effectively control, which has been a long-term problem that the basalt fiber industry has been unable to solve. In recent years, some research attempts to replace the ore raw material to improve the strength and modulus performance of continuous basalt fiber, but due to the inability to solve the natural defects of the ore raw material, an effective preparation method has not been found, resulting in that the continuous basalt fiber product with high strength and high modulus is still blank at present. SUMMARY

[0004] In order to overcome the natural defects of single ore raw material in producing high modulus continuous basalt fiber, the present application improves the tensile strength and tensile modulus performance of the fiber by multi-element mixing and homogenization of the ore, and adding appropriate amount of strengthening and modulus increasing oxides, and introducing trace amount of atmosphere (oxidation or reduction) adjusting agent.

[0005] Specifically, the technical scheme adopted by the present application is as follows: a method for improving the strength and modulus of continuous basalt fiber by multi-element mixing of raw materials, the method comprising the following steps:

[0006] (1) raw material selection: selecting one or more neutral magmatic rocks with SiO2 mass percentage content greater than or equal to 54% and less than 66% as main material, and selecting one or more basic-neutral magmatic rocks with SiO2 mass percentage content greater than or equal to 52% and less than 54% as auxiliary material;

[0007] (2) raw material ratio: determining the chemical composition content of the main material and the auxiliary material selected in step (1) by means of material detection, and determining the ratio of the main material and the auxiliary material according to the target composition content of the mixed material;

[0008] (3) mixing processing: the mixed raw materials are broken, ground, sieved, and the obtained powder is homogenized to obtain a mixed material, and sampling is performed to determine that the actual ingredient content of the mixed material is within the target ingredient content range;

[0009] (4) selection and addition of strengthening and modulus increasing oxides: according to the actual ingredient content of the mixed material and the expected strength and modulus of the continuous basalt fiber product, the type and amount of the added strengthening and modulus increasing oxides are determined;

[0010] (5) selection and addition of atmosphere adjuster: according to the ratio of FeO / (Fe2O3+FeO) in the actual ingredient content of the mixed material, the type and amount of the added atmosphere adjuster are determined;

[0011] (6) mixing and homogenizing the selected strengthening and modulus increasing oxides and the atmosphere adjuster with the mixed material;

[0012] (7) fiber production: the homogenized powder obtained in step (6) is drawn to produce a continuous basalt fiber.

[0013] As used herein, the basic-intermediate magmatic rock and the intermediate magmatic rock refer to the conventional rock classification of magmatic rocks in the art according to the mass percentage content of SiO2.

[0014] Further, the intermediate magmatic rock includes andesite or diorite.

[0015] Further, the basic-intermediate magmatic rock includes basalt, diabase, gabbro, basaltic andesite, diabase andesite, and pyroxene andesite.

[0016] Further, the mass fraction of total iron of the main material is 6%-10%, and the mass fraction of total iron of the mixed material is 7%-12%. As used herein, the total iron refers to the total mass fraction of Fe2O3 and FeO in the ore.

[0017] Further, the mineral fabric of the main material is dense or oblique porphyritic, and the mineral fabric of the mixed material is dense or oblique porphyritic.

[0018] Further, the loss on ignition of the main material and the mixed material is ≤2.0%.

[0019] Further, the target ingredient content of the mixed material in step (2) is: 54%-60% of SiO2, 16%-18% of Al2O3, 7%-11% of Fe2O3+FeO, 6%-10% of MgO, 6%-9% of CaO, 2%-3% of Na2O, 0.5%-1.5% of K2O, and 1%-4% of TiO2.

[0020] Further, in the target composition of the mixed batch, FeO / (Fe2O3+FeO) = 0.4-0.8 by mass.

[0021] Further, in the target composition of the mixed batch, the mass fraction of plagioclase + pyroxene is ≥ 70%.

[0022] Further, the reinforcing and modulus enhancing oxides are selected from one or more of the following: 1) network formers: GeO2, Al2O3, ZrO2, V2O5; 2) network intermediates: Nb2O5, CeO2, Y2O3, Sc2O3, La2O3, TiO2; 3) network modifiers: MgO, Li2O, BeO.

[0023] Further, the reinforcing and modulus enhancing oxides can be added in an amount of 0-20%, for example, 0-15%, 0-10%, etc., which can be adjusted according to the actual composition of the mixed batch and the desired strength and modulus of the continuous basalt fiber product.

[0024] Further, when the ratio of FeO / (Fe2O3+FeO) in the actual composition of the mixed batch is greater than or equal to 0.4 and less than 0.6, a reducing atmosphere adjusting agent is added; when the ratio of FeO / (Fe2O3+FeO) in the actual composition of the mixed batch is equal to 0.6, no atmosphere adjusting agent is added; when the ratio of FeO / (Fe2O3+FeO) in the actual composition of the mixed batch is greater than 0.6 and less than or equal to 0.8, an oxidizing atmosphere adjusting agent is added.

[0025] Further, the atmosphere adjusting agent is added in an amount of 0-3%, which can be adjusted according to the deviation of the ratio of FeO / (Fe2O3+FeO) from 0.6.

[0026] Further, the atmosphere adjusting agent is selected from one or more of the following: 1) oxidizing agents: MnO2, V2O5, CeO2; 2) reducing agents: MnO, citric acid, graphite, oxalic acid.

[0027] Further, in step (3), the sieving is through an 80-100 mesh sieve.

[0028] As used herein, the drawing of the mixed batch powder is carried out using conventional processes well known in the art, for example, the drawing can be carried out using processes such as melting, drawing forming, and dip coating.

[0029] In other aspects, the present application also provides continuous basalt fibers produced by the method described herein.

[0030] Advantages of the application

[0031] In order to solve the natural spinnability defects of the single basalt ore raw material for fiber and the fluctuation problem of the raw material mineral and component content, the inventor previously applied for the invention patent of "a method for improving the production efficiency and fiber performance of continuous basalt fiber by multi-element mixing of raw materials", which discloses a method for solving the production difficulty of single raw material by mixing and homogenizing the raw materials, effectively reducing the gas and electricity consumption of production, improving the fiber forming rate, especially greatly increasing the fiber full barrel rate, and making the tensile strength and tensile elastic modulus of the fiber precursor tend to be stable.

[0032] The present application is an improvement on the above-mentioned patent application. Specifically, the present application adjusts the mass percentage content of the raw material mineral and the main oxides, i.e. the mass percentage content of the network former, the network intermediate and the network modifier oxides, by mixing different raw materials, without changing the "naturalness" and "environmental protection" advantages of continuous basalt fiber, by adding appropriate amount of reinforcing and modulus increasing oxides with high bond strength and no environmental hazards to enhance the integrity of its network structure, and by introducing a small amount of atmosphere (oxidizing or reducing) adjusting agent, to precisely control the ratio of FeO / (Fe2O3+FeO) in the mixture, so that the homogeneity and thermal conductivity of the glass liquid in the fiber drawing process are greatly improved, so as to more accurately control the thermal transmittance and homogeneity of the molten liquid, and to ensure continuous and stable industrial production, thereby improving the strength and modulus of the continuous basalt fiber precursor. DETAILED DESCRIPTION

[0033] The present application will be further described in conjunction with specific examples, but the examples do not limit the present application in any form. Unless otherwise specified, the reagents, methods and equipment used in the present application are conventional reagents, methods and equipment in the technical field.

[0034] Example:

[0035] The present application provides a method for improving the strength and modulus of continuous basalt fiber by multi-element mixing of raw materials, comprising:

[0036] (1) Raw material selection: In this embodiment, the ores from Xiangzhangping basalt mine in Hanxian County, Sichuan Province and Tiesaoqiao diorite in Kangding City, Sichuan Province are selected as the main materials, and the ore from Longzhu Mountain basalt mine in Huili County, Sichuan Province is selected as the ingredient. See Table 1 for specific information.

[0037] Table 1: Multi-element mixed raw material reference points

[0038] No. Ore site Rock type Note 1# Tiesuoqiao diorite mine in Kangding, Sichuan Province Diorite Main material 1-1 2# Xiangzhangping basalt mine in Hanxian County, Sichuan Province Basaltic andesite Main material 1-2 3# Longzhu Mountain basalt mine in Huili County, Sichuan Province Basalt Batching 2-1

[0039] (2) Determine the content of each component in each reference ore. See Table 2

[0040] Table 2: Chemical composition content table of each reference ore

[0041]

[0042] (3)Batching: according to the target content (i.e. > 70% of plagioclase + pyroxene; 54%-60% SiO2, 16%-18% Al2O3, 7%-11% (Fe2O3+FeO), 6%-10% MgO, 6%-9% CaO, 2%-3% Na2O, 0.5%-1.5% K2O, 1%-4% TiO2; FeO / (Fe2O3+FeO) = 0.4-0.8, the batching quality percentage of each mixed batch is calculated according to the content of each component in Table 2. As shown in Table 3, 60 parts of 1-1# main material, 28 parts of 1-2# main material, and 12 parts of 2-1# batch are weighed according to the mass percentage. The comparative example is only composed of single mineral material of Longzhu Mountain basalt (batching) in Huili County, Sichuan Province.

[0043] Table 3: Weight percentage of mixed ore

[0044] Ore point Example 1-6 Comparative example 1-1# (main) 60 0 1-2# (main) 28 0 2-1# (batch) 12 100

[0045] (4) The mixed material of Examples 1-6 is crushed, ground, and processed into powder with a particle size of 80-100 mesh and is subjected to homogenization treatment, and then sampling detection is performed to ensure that the content of each component of the mixed batch is within the required range (if it does not meet the requirements, secondary batching is required), and the mixed powder is obtained. The detection results of the content of each component in the examples and the comparative example are shown in Table 4.

[0046] Table 4: Detection content table of each component after ore batching

[0047]

[0048]

[0049] (5) Adding atmosphere adjuster: the FeO / (Fe2O3+FeO) of the mixed material is 0.52. According to the mass percentage, 0.5% of the weakly reducing oxalic acid is added to the mixed material of each example.

[0050] (6) Adding enhanced and model oxides: according to the main oxide content of the mixed material, as listed in Table 5, the corresponding enhanced and model oxides are added to the mixed material of each example and are subjected to homogenization treatment respectively.

[0051] Table 5: Percentage content of enhanced and model oxides and atmosphere adjuster added to the mixed powder in each example

[0052]

[0053] (7) Fiber production: The mixed powder obtained in the previous step is gradually added to the pool furnace, and after the raw materials in the pool furnace are completely replaced, the melting, fiber drawing and coating process are used for fiber production, and the production parameters are recorded to obtain continuous basalt fibers.

[0054] (8) The production efficiency and fiber performance of basalt fibers were tested, and the results are shown in Table 6.

[0055] Table 6: Basalt fiber raw material melting parameters and fiber performance of each example

[0056]

[0057]

[0058] As can be seen from Table 6: in Example 1, by introducing 0.5% oxalic acid reducing atmosphere modifier, the redox atmosphere of the furnace melting is controlled; at the same time, according to the main chemical composition content of the mixed material, 2.6% TiO2 and 2.0% MgO are further added, so that the content of each main oxide in the raw material tends to be ideal, and the fiber drawing effect and the original strength and modulus of the fiber are obviously better than those of the comparative example.

[0059] In Example 2, based on Example 1, 0.5% Li2O with strong bond energy and small atomic radius is added, and 0.5% Y2O3 and 0.5% CeO2 two kinds of rare earth oxides with strong bond strength are added to increase the percentage content of high-strength and high-modulus oxides, so that the strength and modulus of the fiber precursor are greatly improved.

[0060] In Example 3, based on Example 2, the percentage content of Li2O, Y2O3 and CeO2 oxides is increased to 1%, with the increase of the content of the reinforcing and modulus oxides, the bond force between the reinforcing atoms is increased, and the improvement of the internal crystal structure of the fiber is more obvious, so that the strengthening effect in the fiber is more significant, thereby improving the strength and modulus of the fiber.

[0061] In Example 4, based on Example 3, the percentage content of Y2O3 and CeO2 two kinds of rare earth oxides is increased to 1.5%. This incremental change continuously optimizes the internal structure of the fiber, and through the synergistic effect of rare earth oxides and other components, the crystallization of the fiber is more perfect, and the crystal defects are reduced, thereby improving the overall performance of the fiber.

[0062] In Example 5, based on Example 4, the percentage content of Y2O3 and CeO2 two kinds of rare earth oxides is increased to 2.0%, at this time, the high content of rare earth oxides further strengthens the microstructure of the fiber, so that the stress can be more effectively transmitted and dispersed in the fiber when the fiber is under stress, thereby improving the tensile capacity and carrying capacity of the fiber, and the strength and modulus of the fiber are further improved.

[0063] Example 6 is based on Example 3, with the addition of 1.0% Sc2O3, 1.0% La2O3. The introduction of Sc2O3 and La2O3 further adjusts the crystal structure and chemical bond properties of the fiber, and interacts with other components in the mixture, possibly producing new strengthening phases or changing the distribution of the original phases, thereby continuing to affect the strength and modulus properties of the fiber.

[0064] Compared with Longjushan single basalt ore raw material (comparative example), all examples of the present application have the following advantages: the homogenized mixture of the ore after multi-component mixing and homogenization, with the appropriate addition of strengthening and modulus oxides, and the introduction of trace amounts of atmosphere (oxidizing or reducing) adjustment agents.

[0065] (1) Much higher tensile strength and tensile elastic modulus, all examples have a tensile strength > 2700 MPa and a tensile elastic modulus > 92 GPa, breaking the bottleneck of continuous basalt fiber filaments in China, which have a tensile strength < 2600 MPa and a tensile modulus < 90 GPa. This is because multi-component mixing makes the raw material composition more reasonable, the addition of strengthening and modulus oxides optimizes the internal structure of the fiber, enhances the interatomic bonding, and the atmosphere adjustment agent ensures the stability of the melting process, which together improves the modulus of the fiber.

[0066] (2) Lower melting temperature, forming temperature and liquidus temperature that can be implemented in industrial production. In the process of multi-component mixing, the reasonable collocation of raw materials reduces the energy demand of the system, and the atmosphere adjustment agent helps to reduce the viscosity of the melt and improve its flowability, so that good melting, forming and other processes can be achieved at lower temperatures, which is beneficial to energy saving and process control in industrial production.

[0067] (3) Higher fiberizing rate and full bucket rate to ensure the economic benefits of high modulus filament product production. Multi-component mixing reduces the production instability factors caused by defects of single ore raw material, and the synergistic effect of strengthening and modulus oxides and atmosphere adjustment agents further improves the stability of the production process, so that the fiber is more easily formed and has more stable quality in the production process, thereby improving the fiberizing rate and full bucket rate.

[0068] It should be noted that the preferred embodiments of the present application are described in the specification and its drawings only for the purpose of better understanding the present application, and the present application can be implemented in many different forms, and is not limited to the embodiments described in the specification, and these embodiments are not intended to be additional limitations on the content of the present application, and the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. Furthermore, each of the above technical features continues to be combined with each other, forming various embodiments not listed above, which are all considered to be within the scope of the present application specification; further, for those skilled in the art, the above description can be improved or changed, and all these improvements and changes shall fall within the scope of protection of the claims of the present application.

Claims

1. A continuous basalt fiber produced by drawing from a raw material polyblended via a drawing process, characterized in that, The component content of the mixed powder for wire drawing production obtained by mixing multiple raw materials is: 50.54%-52.95% of SiO2, 14.86%-15.57% of Al2O3, 3.48%-3.64% of Fe2O3, 3.78%-3.96% of FeO, 7.57%-7.94% of MgO, 7.50%-7.86% of CaO, 2.32%-2.43% of Na2O, 0.74%-0.78% of K2O, 3.59%-3.76% of TiO2, 0.45%-0.48% of H2C2O4, 0%-0.93% of Li2O, 0%-1.82% of CeO2, 0%-1.82% of Y2O3, 0%-0.91% of La2O3 and 0%-0.91% of Sc2O3, by mass percentage; And the continuous basalt fiber produced by wire drawing production through the multi-element mixing of raw materials is made by a method comprising the following steps: (1) raw material selection: selecting one or more neutral magmatic rocks with a mass percentage of SiO2 greater than or equal to 54% and less than 66% as the main material, and selecting one or more basic-neutral magmatic rocks with a mass percentage of SiO2 greater than or equal to 52% and less than 54% as the ingredient; (2) raw material ratio: determining the chemical component content of the main material and the ingredient selected in step (1) by means of material detection, and determining the ratio of the main material and the ingredient according to the target component content of the mixed material; (3) mixing processing: mixing the raw materials after ratioing, crushing, grinding, sieving, and homogenizing the obtained powder to obtain a mixed material, and sampling and detecting to determine that the actual component content of the mixed material is within the target component content range; (4) selection and addition of strengthening and modulus increasing oxides: determining the type and amount of added strengthening and modulus increasing oxides according to the actual component content of the mixed material and the expected strength and modulus of the continuous basalt fiber product; (5) selection and addition of atmosphere adjusting agent: determining the type and amount of added atmosphere adjusting agent according to the ratio of FeO / (Fe2O3+FeO) in the actual component content of the mixed material; (6) mixing the selected strengthening and modulus increasing oxides and atmosphere adjusting agent with the mixed material and homogenizing to obtain a mixed powder for wire drawing production; (7) fiber production: wire drawing production of the mixed powder obtained in step (6) to obtain a continuous basalt fiber.

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