Oriented steel fiber reinforced refractory material, its preparation method and application

Abstract

The application discloses an oriented steel fiber reinforced refractory material and a preparation method and application thereof, and belongs to the technical field of refractory materials. The preparation method of the oriented steel fiber reinforced refractory material comprises the following steps: making a refractory material mixed slurry containing a first component and a second component flow downwards along a barrel of an extrusion type 3D printing device and being extruded by a nozzle, and being formed into the oriented steel fiber reinforced refractory material through extrusion 3D printing, wherein the first component contains refractory material aggregate, silicon powder, steel fiber and a curing agent, the second component contains a binder, a plasticizer and a water reducing agent, and the viscosity of the refractory material mixed slurry is 15000-30000 mPa s under a shear rate of 0.4 S ‑1 , and the viscosity is 3500-5500 mPa s under a shear rate of 30.59 S ‑1 , and the thixotropic loop area is not less than 120 Pa / s. The application can not only be used for forming a complex structure, especially a special-shaped steel fiber reinforced refractory material, but also can effectively improve the orientation distribution of the steel fiber in the refractory material, so that the toughening effect is ensured.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of refractory materials, and particularly relates to an oriented steel fiber reinforced refractory material and a preparation method and application thereof. BACKGROUND

[0002] Due to the introduction of steel fibers, the steel fiber reinforced refractory material has excellent fracture toughness, mechanical properties and thermal shock resistance, and is widely used in key parts of high-temperature industries (such as steel, cement, etc.) with severe wear and tear and harsh service environment. In general, the load and working conditions of the steel fiber reinforced refractory material are relatively fixed during use, and the main stress direction of the refractory material is basically consistent. However, the steel fibers are randomly distributed in the material (the theoretical analysis value of the steel fiber orientation factor is 0.405), and only a small number of steel fibers are oriented in the load or stress direction, which affects the use performance of the steel fiber reinforced refractory material.

[0003] In view of the above problems, the applicant has carried out relevant research and has obtained certain research results (Minghui Li, Peilin Li, Gang Qi, Saisai Li*, Ruoyu Chen*, Siwei Lv, Yi Ding, and Canhua Li. Enhancing mechanical properties and thermal shock resistance of steel fiber reinforced mullite castable through magnetic field treatment [J]. Construction and Building Materials, 2024, (432): 136668.), which discloses a method for orienting steel fibers in refractory castables by using an external magnetic field, and excellent performance is achieved, in which the steel fiber orientation factor can reach 0.96. Compared with traditional steel fiber reinforced refractory materials, the oriented steel fiber reinforced refractory material has an increase of 6.57% in cold modulus of rupture, 56.73% in ultimate flexural toughness, 26.24% in fracture energy, and 18.62% in high-temperature modulus of rupture, and in addition, the thermal shock resistance is also significantly improved, greatly improving the comprehensive performance of the material.

[0004] Meanwhile, although no other literature on steel fiber orientation has been found in the field of refractory materials, there are patent disclosures related to steel fiber orientation in the field of concrete. For example, Chinese patent CN114368055A discloses a planar oriented steel fiber concrete preparation device. This application achieves magnetically controlled planar orientation of steel fibers through a combination of rotating magnetic fields and repulsive magnetic fields, thus preparing planar oriented steel fiber concrete. The steel fibers are parallel to the two-dimensional stress direction of the plane and distributed accordingly, significantly improving the steel fiber reinforcement effect and thereby improving the mechanical properties of the concrete.

[0005] Although the aforementioned literature has produced high-performance oriented steel fiber reinforced refractory materials or concrete using an external magnetic field, the implementation process of the above-mentioned steel fiber magnetic orientation method is complex. It requires the placement of coils outside the mold or the assistance of an external strong magnet, and the preparation conditions are demanding. To avoid interference with the magnetic field strength, metal molds cannot be used. These technical and operational limitations have prevented the application of steel fiber magnetic orientation in actual industry to date, especially for irregularly shaped parts with complex structures and different orientation requirements for steel fibers in actual industrial production, which is even more inconvenient to implement. Summary of the Invention

[0006] The purpose of this invention is to provide a grain-oriented steel fiber reinforced refractory material, its preparation method, and its application, thereby solving the problems in existing technologies where it is difficult to prepare high-performance grain-oriented steel fiber reinforced refractory materials, or where the preparation process is complex, the implementation conditions are harsh, and it is difficult to promote industrial application. The steel fiber reinforced refractory material prepared by this invention not only has advantages such as high mechanical strength and high fracture toughness, but also has a simple and easy-to-implement preparation process, which is especially convenient for preparing irregularly shaped components.

[0007] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0008] The first aspect of this invention provides a method for preparing a fiber-reinforced refractory material, comprising:

[0009] The refractory material mixture containing the first and second components is made to flow downward along the barrel of the extrusion 3D printing device and be extruded through the nozzle. The oriented steel fiber reinforced refractory material is obtained by extrusion 3D printing.

[0010] The first component comprises refractory aggregate, silica fume, steel fiber, and curing agent; the second component comprises binder, plasticizer, and water-reducing agent; and the refractory mixture slurry has a shear rate of 0.4S. -1 The viscosity is 15000–30000 mPa·s, and the shear rate is 30.59 s. -1The viscosity of the slurry is 3500-5500 mPa·s, and the thixotropic loop area is not less than 120 Pa / s.

[0011] In view of the technical problem that it is difficult to prepare an oriented steel fiber reinforced refractory material with excellent performance in the prior art, the present application adopts an extrusion type 3D printing forming technology, and optimizes the components of the refractory material mixed slurry, wherein the first component mainly serves as a refractory material base, and the second component serves as an additional additive, mainly for regulating the rheological property of the base slurry, so as to not only be used for forming a complex structure, especially a special-shaped steel fiber reinforced refractory material, but also effectively improve the orientation distribution of the steel fiber in the refractory material, thereby ensuring the toughening effect.

[0012] It should be noted that the research group of the present inventors has been engaged in the research of the oriented steel fiber reinforced refractory material, and the orientation distribution of the steel fiber in the refractory castable has been improved by the action of an external magnetic field, but on the one hand, the above technical operation is relatively complex and is not convenient for industrial popularization and application; on the other hand, the steel fiber is greatly oriented and deflected under the magnetic induction, resulting in voids in the refractory material, which has an adverse effect on the material performance.

[0013] Based on the above, specifically, the present application uses the extrusion 3D printing forming technology, and after the refractory material slurry mixed with steel fibers is loaded into the barrel, on the one hand, the difference in flow rate of each component in the slurry (friction of the barrel side wall) causes the steel fiber to rotate, thereby promoting the axial direction of the steel fiber to be parallel or at a certain small inclination angle to the extrusion direction; on the other hand, the closer to the nozzle, the smaller the diameter of the barrel, so that the barrel side wall provides additional resistance to the steel fiber during the extrusion forming process, ensuring the effectiveness of the orientation of the steel fiber, so that the direction distribution of the steel fiber is basically consistent during extrusion, overcoming the influence of the voids generated after the steel fiber is greatly oriented and deflected in the magnetic induction orientation process on the material performance.

[0014] In addition, the present application further optimizes the rheological property of the refractory material mixed slurry, so as to improve the rheological property of the slurry on the basis of meeting the performance requirements and 3D printing forming requirements of the refractory material itself, so as to effectively fill the voids generated after the steel fiber is deflected by the refractory material at other positions, thereby ensuring the performance of the final product.

[0015] According to any of the technical solutions of the first aspect of the present application, the binder comprises at least one of dextrin, corn starch, sodium carboxymethyl cellulose (CMC), and / or the plasticizer comprises bentonite, and / or the water reducing agent comprises sodium hexametaphosphate or polycarboxylate; and / or the curing agent comprises calcium aluminate cement.

[0016] As a further preferred solution, the binder adopts sodium carboxymethyl cellulose, the plasticizer adopts bentonite, and / or the water reducing agent adopts polycarboxylate FS20, through the additional addition and joint action of the three additives, especially through the complexing action of sodium carboxymethyl cellulose and bentonite, the rheological properties of the refractory mixed slurry can be effectively improved, not only the extrudability and continuous building capability of the material in the 3D printing process can be ensured, but also excellent interlayer bonding force can be maintained; in addition, the voids generated in the material after the deflection of the steel fiber can be effectively prevented.

[0017] Specifically, the addition of CMC adjusts the rheological properties of the matrix slurry, enhances the shear thinning behavior and thixotropy, and increases the yield stress; the excellent thixotropy can make the material quickly recover to the original state after extrusion molding, which is beneficial to maintaining the structural stability. As a plasticizer, bentonite improves the thixotropic properties of the slurry by forming gel-like substances through water absorption and expansion, increases the plasticity, further enhances the structural stability of the 3D printing material, and optimizes the printability. Under the joint action of CMC and bentonite, the prepared refractory material has extrudability and good structural stability in the 3D printing process, and can effectively fill the voids generated in the material after the deflection of the steel fiber.

[0018] Meanwhile, by adding part of silicon powder in the base material, on the one hand, since the particle size of the silicon powder is relatively small, the specific surface area and surface energy are relatively high, therefore the spacing of the powder particles in the matrix slurry decreases with the increase of the addition amount of the silicon powder, so that the interaction between the particles can be improved, the rheological properties of the slurry can be further adjusted, and the thixotropy of the slurry can be increased. On the other hand, the addition of silicon powder can also enhance the shear thinning behavior of the matrix slurry, and the shear thinning characteristics are beneficial to further adjusting the orientation of the steel fiber in the matrix during the extrusion of the steel fiber. In addition, increasing the addition amount of silicon powder also makes the slurry have higher yield stress, which is helpful to improve the stability of the refractory material.

[0019] According to any of the technical solutions of the first aspect of the present application, the addition amount of the binder accounts for 0.05%-0.3% of the total amount of the first component, and / or

[0020] The addition amount of the plasticizer accounts for 0.5%-3% of the total amount of the first component, and / or

[0021] The addition amount of the water reducing agent accounts for 0.05%-0.2% of the total amount of the first component; and / or

[0022] The addition amount of the curing agent accounts for 4%-7% of the total amount of the first component; and / or

[0023] The addition amount of the steel fiber accounts for 1%-5% of the total amount of the first component, and / or

[0024] The adding amount of the silicon powder is 5%-8% of the total amount of the first component; and / or

[0025] The refractory mixed slurry further contains water, which is 14%-18% of the total amount of the first component.

[0026] It should be noted that the content of the above-mentioned additives can be any range of values within the above-mentioned range, or any point value within the above-mentioned range, for example, the adding amount of the binder can be 0.05%-0.1%, 0.15%-0.25%, 0.1%-0.2%, 0.2%-0.3%, etc., or 0.05%, 0.1%, 0.15%, 0.25%, 0.3%, etc.

[0027] According to any of the technical solutions of the first aspect of the present application, the refractory aggregate comprises the following components by mass fraction: 45-60 parts of mullite, 15-25 parts of andalusite, 2-5 parts of silicon carbide, 5-10 parts of corundum powder, and 5-7 parts of active alumina powder.

[0028] According to any of the technical solutions of the first aspect of the present application, the sum of the mass of the silicon powder and the active alumina powder is 10%-15% of the total amount of the first component.

[0029] According to any of the technical solutions of the first aspect of the present application, the mullite is composed of 0-1mm particle size and fine powder with particle size less than 325 mesh, and the mass ratio is 20:3-25:3; and / or

[0030] The particle size of the andalusite is less than 1mm; and / or

[0031] The particle size of the silicon carbide is less than 1mm; and / or

[0032] The particle size of the corundum powder is less than 325 mesh; and / or

[0033] The particle size of the active alumina powder is less than 325 mesh; and / or

[0034] The particle size of the silicon powder is less than 325 mesh; and / or

[0035] The length of the steel fiber is 10mm, and the equivalent diameter is 0.7mm.

[0036] By optimizing the particle size distribution of each component, not only the rheological properties of the slurry can be improved, but also the extrudability and stackability can be improved, the density of the sample can be improved, the internal pores of the sample can be reduced, the strength of the sample can be effectively improved, and the mechanical properties of the sample can be improved.

[0037] According to any of the technical solutions of the first aspect of the present application, the nozzle of the extrusion 3D printing device is made of non-metallic material, and a coil is wound outside the nozzle, and a magnetic field is generated when the coil is connected to a power supply, so that the steel fiber is further ensured to be distributed along the direction parallel to the extrusion direction when the refractory material mixed slurry is extruded from the nozzle. By applying a certain external magnetic field to the slurry during extrusion, the orientation distribution of the steel fiber is further improved, and the directional effect coefficient of the steel fiber is further improved.

[0038] According to any of the technical solutions of the first aspect of the present application, the process parameters of the extrusion 3D printing forming include that the printing speed is 130-150 mm / s, the layer height is 20-30 mm, and the magnetic field size of the coil is 2.5-5 mT. The effectiveness of 3D printing depends largely on the printing parameters. When the printing parameters match the model, it helps to reduce structural defects. Otherwise, the green body will be deformed, causing the slurry to accumulate, thereby adversely affecting the performance of the material.

[0039] According to any of the technical solutions of the first aspect of the present application, the process parameters of the extrusion 3D printing forming include that the printing speed is 130-150 mm / s, the layer height is 20-30 mm, and the magnetic field size of the coil is 2.5-5 mT. The effectiveness of 3D printing depends largely on the printing parameters. When the printing parameters match the model, it helps to reduce structural defects. Otherwise, the green body will be deformed, causing the slurry to accumulate, thereby adversely affecting the performance of the material.

[0040] The second aspect of the present application provides an oriented steel fiber reinforced refractory material prepared by the method of the first aspect of the present application.

[0041] According to any of the technical solutions of the second aspect of the present application, the directional effect coefficient of the steel fiber of the oriented steel fiber reinforced refractory material is not less than 0.90, the limiting bending toughness at 1100℃×3h is (200-260)×10 -3 J, and the limiting bending toughness at 1350℃×3h is (145-160)×10 -3 J.

[0042] The third aspect of the present application further provides an oriented steel fiber reinforced refractory material, the directional effect coefficient of the steel fiber of which is not less than 0.90, the limiting bending toughness at 1100℃×3h is (200-260)×10 -3 J, and the limiting bending toughness at 1350℃×3h is (145-160)×10 -3 J.

[0043] The fourth aspect of the present application further provides an application of the oriented steel fiber reinforced refractory material of the second aspect or the third aspect of the present application or prepared by the method of the first aspect of the present application in refractory castable.

[0044] In summary, compared with the prior art, the technical scheme provided by the present application can achieve the following beneficial effects:

[0045] (1) The present application uses extrusion 3D printing forming technology to prepare steel fiber reinforced refractory materials, and optimizes the rheological properties of the refractory material mixed slurry, so that it can not only be used for forming complex structures, especially special-shaped steel fiber reinforced refractory materials, but also effectively improve the orientation distribution of steel fibers in the refractory material, thereby ensuring the toughening effect and preventing the formation of voids in the material after the orientation of the steel fibers deviates.

[0046] (2) By using extrusion 3D printing forming technology, the steel fibers can be laid out specifically during the printing process, and the distribution of the steel fibers can be optimized. The oriented steel fiber reinforced refractory material prepared has significantly improved mechanical strength and bending toughness compared with traditional steel fiber reinforced refractory materials. This is because the orientation of the steel fibers enhances the effectiveness of bridging cracks and dispersing stress in the material matrix, enhancing the nonlinear elastic-plastic behavior of the material. At the same time, the orientation of the steel fibers makes the crack propagation path during the fracture process complex, resulting in crack deflection and crack branching, enhancing the material's ability to resist crack propagation, effectively alleviating the formation and development of cracks in the matrix, and fully utilizing the tensile and bridging effect of the steel fibers.

[0047] (3) The present application adds specific types of binders, plasticizers and water reducing agents, especially by compounding bentonite and sodium carboxymethyl cellulose, and optimizes the content, thereby effectively ensuring the rheological properties of the obtained refractory material mixed slurry.

[0048] (4) The present application further winds a coil outside the nozzle of the extrusion type 3D printing device, so that when the mixed steel fiber refractory material passes through the nozzle, the energized coil around the nozzle generates a magnetic field under the current, causing the steel fibers with a certain inclination angle to be parallel to the extrusion direction under the action of the magnetic field, further improving the steel fiber orientation factor. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 is a preparation flowchart of oriented steel fiber reinforced refractory materials;

[0050] Figure 2 is a schematic diagram of the 3D printing process to achieve steel fiber orientation;

[0051] Figure 3 is a schematic diagram of the steel fiber direction effect coefficient test;

[0052] Figure 4 is a strain image of the steel fiber reinforced refractory material in the X-axis direction;

[0053] Figure 5 A scanning picture of the steel fiber reinforced refractory material. DETAILED DESCRIPTION

[0054] In order to further understand the content of the present application, the present application will be described in detail in combination with specific embodiments. In order to avoid repetition, the technical parameters involved in the specific embodiments will be described uniformly as follows, and the embodiments will not be described in detail. However, it should be noted that the particle size of each component is not limited by the numerical values in the embodiments.

[0055] The mullite is a fine powder with a particle size of 0-1 mm and a particle size of less than 325 mesh;

[0056] The andalusite is a particle with a particle size of 0-1 mm;

[0057] The silicon carbide is a particle with a particle size of 0-1 mm;

[0058] The active alumina powder and the silicon powder are a fine powder mixture with a particle size of less than 325 mesh;

[0059] The dense corundum fine powder is a fine powder with a particle size of less than 325 mesh;

[0060] The calcium aluminate cement is Secar 71;

[0061] The steel fiber is a 446# melt-drawing steel fiber with a length of 10 mm and an equivalent diameter of 0.7 mm.

[0062] Example 1

[0063] The preparation method of the oriented steel fiber reinforced refractory material of the present embodiment comprises:

[0064] Step one, 46 parts of mullite, 20 parts of andalusite, 3 parts of silicon carbide, 10 parts of dense corundum fine powder, 6 parts of active alumina powder, 7 parts of silicon powder, 5 parts of calcium aluminate cement, 3 parts of steel fiber, 0.2 parts of sodium carboxymethyl cellulose, 1.5 parts of bentonite and 0.1 parts of FS20 are mixed by a planetary ball mill for 10 minutes according to the mass fraction; after uniform mixing, 14 parts of water are added and wet mixed for 10 minutes to obtain a pre-printed refractory material, wherein the rotation speed is set to 350 r / min.

[0065] Step two, after uniform mixing, an oriented steel fiber reinforced refractory material is prepared by an extrusion type 3D printing device according to a speed of 130 mm / s, a layer height of 20 mm, and a magnetic field size of 2.5 mT passing through the coil. At the same time, as shown in Figure 2 The nozzle of the extrusion type 3D printing device is made of non-metallic material, and the outside of the nozzle is wound with a coil, and the coil is connected with a power supply to generate a magnetic field, so that the steel fiber is distributed parallel to the extrusion direction under the action of the magnetic field.

[0066] Example 2

[0067] The preparation method of the oriented steel fiber reinforced refractory material of the embodiment comprises:

[0068] Step one, 49 parts of mullite, 21 parts of andalusite, 2.5 parts of silicon carbide, 9 parts of dense corundum powder, 5 parts of active alumina powder, 6 parts of silica powder, 5 parts of calcium aluminate cement, 2.5 parts of steel fiber, 0.2 parts of sodium carboxymethyl cellulose, 2 parts of bentonite and 0.075 parts of FS20 are mixed by a planetary ball mill for 12 min according to the formula; after uniform mixing, 16 parts of water is added and wet mixed for 12 min to obtain a pre-printing refractory material, wherein the rotation speed is set to 350 r / min.

[0069] Step two, after uniform mixing, the oriented steel fiber reinforced refractory material is prepared by an extrusion type 3D printing device at a speed of 140 mm / s, a layer height of 25 mm and a magnetic field size of 5 mT passed into a coil. Meanwhile, the nozzle of the extrusion type 3D printing device is made of non-metallic material, which is externally wound with a coil, and the coil is externally connected with a power supply to generate a magnetic field, so that the steel fiber is distributed in parallel with the extrusion direction under the action of the magnetic field.

[0070] Example 3

[0071] The preparation method of the oriented steel fiber reinforced refractory material of the embodiment comprises:

[0072] Step one, 50 parts of mullite, 18 parts of andalusite, 2 parts of silicon carbide, 10 parts of dense corundum powder, 6 parts of active alumina powder, 7 parts of silica powder, 4 parts of calcium aluminate cement, 3 parts of steel fiber, 0.15 parts of sodium carboxymethyl cellulose, 2 parts of bentonite and 0.1 parts of FS20 are mixed by a planetary ball mill for 14 min according to the formula; after uniform mixing, 18 parts of water is added and wet mixed for 14 min to obtain a pre-printing refractory material, wherein the rotation speed is set to 350 r / min.

[0073] Step two, after uniform mixing, the oriented steel fiber reinforced refractory material is prepared by an extrusion type 3D printing device at a speed of 150 mm / s, a layer height of 30 mm and a magnetic field size of 3.5 mT passed into a coil. Meanwhile, the nozzle of the extrusion type 3D printing device is made of non-metallic material, which is externally wound with a coil, and the coil is externally connected with a power supply to generate a magnetic field, so that the steel fiber is distributed in parallel with the extrusion direction under the action of the magnetic field.

[0074] Comparative Example 1

[0075] The preparation method of the steel fiber reinforced refractory material of the comparative example is mainly different from that of Example 3 in that the refractory material mixed slurry is prepared by vibration molding in the comparative example.

[0076] Comparative Example 2

[0077] The preparation method of the steel fiber reinforced refractory material of the present comparative example is basically the same as that of Example 3, and the main difference is that the raw material composition of the refractory material of the present comparative example is different, and no bentonite is added in the present comparative example.

[0078] Comparative Example 3

[0079] The preparation method of the steel fiber reinforced refractory material of the present comparative example is basically the same as that of Example 3, and the main difference is that the raw material composition of the refractory material of the present comparative example is different, and no bentonite is added in the present comparative example.

[0080] Comparative Example 4

[0081] The preparation method of the steel fiber reinforced refractory material of the present comparative example is basically the same as that of Example 3, and the main difference is that the raw material composition of the refractory material of the present comparative example is different, and no bentonite is added in the present comparative example.

[0082] Comparative Example 5

[0083] The preparation method of the steel fiber reinforced refractory material of the present comparative example is basically the same as that of Example 3, and the main difference is that the raw material composition of the refractory material of the present comparative example is different, and no bentonite is added in the present comparative example.

[0084] Example 4

[0085] The preparation method of the oriented steel fiber reinforced refractory material of the present example is basically the same as that of Example 3, and the main difference is that the coil is not powered during extrusion printing in the present example, and the direction effect coefficient of the steel fiber in the obtained refractory material is 0.9.

[0086] Example 5

[0087] The preparation method of the oriented steel fiber reinforced refractory material of the present example is basically the same as that of Example 3, and the main difference is that corn starch is used as an additional binder and sodium hexametaphosphate is used as a water reducing agent in the present example. The rheological property of the refractory material mixed slurry in the present example is slightly worse than that of Example 3, and the bending strength and ultimate bending toughness of the obtained refractory material are also lower than those of Example 3.

[0088] Example 6

[0089] The preparation method of the oriented steel fiber reinforced refractory material of the present example includes:

[0090] Step one, according to the formula, 55 parts of mullite, 15 parts of andalusite, 5 parts of silicon carbide, 5 parts of dense corundum powder, 7 parts of active alumina powder, 5 parts of silica powder, 7 parts of calcium aluminate cement, 1 part of steel fiber, 0.3 parts of sodium carboxymethyl cellulose, 0.5 parts of bentonite and 0.2 parts of polycarboxylate are mixed by a planetary ball mill for 15 min; after mixing uniformly, 15 parts of water is added and wet mixed for 12 min to obtain a pre-printed refractory material, wherein the rotation speed is set to 380 r / min.

[0091] Step two, after mixing uniformly, an oriented steel fiber reinforced refractory material is prepared by an extrusion type 3D printing device at a speed of 140 mm / s and a layer height of 22 mm. Meanwhile, the nozzle of the extrusion type 3D printing device is made of non-metallic material, and a coil is wound outside the nozzle, and the coil is connected to a power source to generate a magnetic field, so that the steel fibers are distributed in parallel with the extrusion direction under the action of the magnetic field.

[0092] Example 7

[0093] The preparation method of the oriented steel fiber reinforced refractory material of the embodiment comprises:

[0094] Step one, according to the formula, 60 parts of mullite, 15 parts of andalusite, 2 parts of silicon carbide, 5 parts of dense corundum powder, 5 parts of active alumina powder, 5 parts of silica powder, 4 parts of calcium aluminate cement, 4 parts of steel fiber, 0.25 parts of sodium carboxymethyl cellulose, 3 parts of bentonite and 0.15 parts of sodium hexametaphosphate are mixed by a planetary ball mill for 15 min; after mixing uniformly, 18 parts of water is added and wet mixed for 14 min to obtain a pre-printed refractory material, wherein the rotation speed is set to 340 r / min.

[0095] Step two, after mixing uniformly, an oriented steel fiber reinforced refractory material is prepared by an extrusion type 3D printing device at a speed of 145 mm / s and a layer height of 26 mm. Meanwhile, the nozzle of the extrusion type 3D printing device is made of non-metallic material, and a coil is wound outside the nozzle, and the coil is connected to a power source to generate a magnetic field, so that the steel fibers are distributed in parallel with the extrusion direction under the action of the magnetic field.

[0096] As shown in Table 1, the rheological properties of the slurries obtained in Examples 1-7 and Comparative Examples 1-5, Table 2 shows the physical properties of the refractory materials obtained in Examples 1-7 and Comparative Examples 1-5, and Tables 1, 2 and Figures 3-5 As shown in Tables 1, 2 and 3, by using the extrusion type 3D printing forming technology, the orientation distribution of the steel fibers in the refractory material can be effectively improved, and the directional effect coefficient of the steel fibers is effectively improved; and the strain images of the steel fiber reinforced refractory materials of Examples 1-3 and Comparative Example 1 after being treated at 1100℃ in the X-axis direction Figure 4It can be seen that all the samples have crack deflection, and the crack deflection of the sample prepared by the 3D printing forming technology is more serious than that of the sample prepared by the comparative casting method, and the sample has crack branching. The crack deflection and branching make the crack propagation path complex, and the stress resistance of the sample is enhanced.

[0097] At the same time, due to the relatively good rheological properties of the slurries obtained in Examples 1-3 compared to the slurry obtained in Example 5, not only can the needs of 3D printing be met, but also the voids left in the material after the deflection of the steel fibers can be effectively prevented, thereby ensuring the structural strength and bending toughness of the obtained refractory material. As known from Example 4, the orientation distribution of the steel fibers in the refractory material prepared by the extrusion type 3D printing forming technology without an external magnetic field is relatively low, and the directional effect coefficient of the steel fibers is low, but is still higher than that of the ordinary casting method. This is mainly because the refractory material and the steel fibers in the barrel are extruded to produce different moving speeds, and the difference in flow rate causes the rotation of the steel fibers, so that the axial direction tends to the flow direction of the refractory material. On the other hand, the steel fibers contact the side wall of the barrel, inducing the orientation of the steel fibers.

[0098] However, when only the binder or the plasticizer is added in Comparative Example 2 and Comparative Example 3, the rheological properties are reduced, because CMC as a polymer can increase the interaction between bentonite particles, thereby increasing the overall viscosity of the slurry.

[0099] Table 1 Rheological properties of the slurries obtained in Examples 1-7 and Comparative Examples 1-5

[0100]

[0101] Table 2 Physical properties of the refractory materials obtained in Examples 1-7 and Comparative Examples 1-5

[0102]

[0103]

Claims

1. A method for the production of an oriented steel fiber reinforced refractory material, characterized in that, The application relates to an oriented steel fiber reinforced refractory material and a preparation method thereof. The refractory material aggregate comprises the following components in mass fractions: 45-60 parts of mullite, 15-25 parts of andalusite, 2-5 parts of silicon carbide, 5-10 parts of corundum fine powder and 5-7 parts of active alumina micro powder. The first component comprises refractory aggregate, silicon powder, steel fiber and curing agent, the second component comprises binder, plasticizer and water reducing agent, and the viscosity of the refractory mixed slurry is 15000-30000 mPa s under the shear rate of 0.4 S -1 , the viscosity is 3500-5500 mPa s under the shear rate of 30.59 S -1 , and the thixotropic loop area is not less than 120 Pa / s; the added amount of the steel fiber accounts for 1-5% of the total amount of the first component, the binder is sodium carboxymethyl cellulose, the plasticizer comprises bentonite, and the water reducing agent comprises polycarboxylate. The nozzle of the extrusion 3D printing device is made of a nonmetal material, and a coil is wound outside the nozzle; when the coil is connected with a power supply, a magnetic field is generated, so that when the refractory material mixed slurry is extruded from the nozzle, the steel fibers are further ensured to be distributed in parallel to the extrusion direction. The process parameters of the extrusion 3D printing forming include that the printing speed is 130-150 mm / s, the layer height is 20-30 mm, and the magnetic field size of the coil is 2.5-5 mT. The curing agent comprises calcium aluminate cement.

2. A method of producing an oriented steel fiber reinforced refractory material according to claim 1, characterized in that, The adding amount of the plasticizer accounts for 0.5%-3% of the total mass of the first component, and / or 3. A method of producing an oriented steel fibre reinforced refractory material according to claim 1 or 2, c h a r a c t e r i s e d in that, The adding amount of the plasticizer accounts for 0.5%-3% of the total mass of the first component, and / or The adding amount of the water reducing agent accounts for 0.05%-0.2% of the total mass of the first component; and / or The adding amount of the curing agent accounts for 4%-7% of the total mass of the first component; and / or The adding amount of the silicon micro powder accounts for 5%-8% of the total mass of the first component; and / or The refractory material mixed slurry further contains water which accounts for 14%-18% of the total mass of the first component. The sum of the mass of the silicon micro powder and the active alumina micro powder accounts for 10%-15% of the total mass of the first component; and / or 4. A method of producing an oriented steel fibre reinforced refractory material according to claim 3, characterised in that, The mullite is composed of a particle size of 0-1 mm and a fine powder with a particle size less than 325 meshes in a mass ratio of 20:3-25:3; and / or The particle size of the andalusite is less than 1 mm; and / or The particle size of the silicon carbide is less than 1 mm; and / or The particle size of the corundum fine powder is less than 325 meshes; and / or The particle size of the active alumina micro powder is less than 325 meshes; and / or The particle size of the silicon micro powder is less than 325 meshes; and / or The length of the steel fiber is 10 mm, and the equivalent diameter is 0.7 mm. The application further relates to a preparation method of the oriented steel fiber reinforced refractory material.

5. A method of producing an oriented steel fibre reinforced refractory material according to claim 3, characterised in that, The method comprises the following steps: sufficiently mixing raw materials containing the first component and the second component to obtain a refractory material mixture; and adding water to the refractory material mixture for wet grinding to obtain a refractory material mixed slurry. The oriented steel fiber reinforced refractory material is prepared by the method in any one of claims 1-5.

8. Application of the oriented steel fiber reinforced refractory material in claim 6 or 7 in refractory castable.

6. Oriented steel fiber reinforced refractory material, characterized in that, ​ 7. Oriented steel fiber reinforced refractory material according to claim 6, characterized in that The orientation steel fiber reinforced refractory material has a steel fiber direction effect coefficient of not less than 0.90, and an ultimate bending toughness at 1100 DEG C x 3h of (200-260) x 10 -3 J. The ultimate bending toughness at 1350 DEG C x 3h is (145-160) x 10 -3 J. ​

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