A built-in ceramic fiber reinforced heat shock resistant refractory brick

Abstract

The utility model discloses a kind of built-in ceramic fiber reinforced thermal shock resistance firebrick, specifically related to firebrick technical field, including firebrick body, the firebrick body is sequentially included from outside to inside with outer fireproof layer, ceramic fiber reinforced layer and inner fireproof layer, the outer fireproof layer and inner fireproof layer are high-purity bauxite clinker and high-quality mullite powder mixed material quality.The utility model is through outer fireproof layer, inner fireproof layer and ceramic fiber reinforced layer mutual effect, effectively reduce the damage of thermal stress to brick structure;The three-dimensional interlocking net structure of silicon-aluminum ceramic fiber in ceramic fiber reinforced layer and self-adapting gradient distribution, can all-around disperse thermal stress, prevent crack generation and expansion, high-density fiber area preferentially absorbs and buffers high thermal stress, low-density area adjusts stress distribution, ensure that firebrick has high refractoriness and high strength, can bear high-temperature environment and mechanical load.

Description

Technical Field

[0001] This utility model relates to the field of refractory brick technology, and more specifically, to a thermal shock refractory brick reinforced with built-in ceramic fibers. Background Technology

[0002] In high-temperature industries such as steel, building materials, and chemicals, refractory bricks are key structural materials for thermal equipment such as industrial kilns and heat treatment equipment. Their performance directly affects the operational stability and service life of the equipment. As industrial production develops towards high temperature, high efficiency, and energy saving, the working environment of thermal equipment is becoming increasingly harsh. It not only needs to withstand temperatures above 1000℃ for a long time, but also needs to frequently experience drastic temperature changes during furnace start-up and shutdown. The resulting thermal stress has become one of the main causes of refractory brick damage.

[0003] A search revealed that Chinese patent CN218492835U discloses a refractory brick. Through the combination of the refractory brick body, wear-resistant layer, polyurea coating layer, polyurethane coating layer, phenolic resin coating layer, positioning groove, outer slot, inner slot, connecting plate and elastic clip, it achieves the advantage of good wear resistance. This solves the problem that existing refractory bricks have poor wear resistance during use, and the bottom of the refractory brick is often easily worn, which affects its service life and makes it inconvenient for people to use.

[0004] Although this refractory brick has a certain degree of refractoriness and mechanical strength, it is prone to internal cracks under thermal shock conditions due to the lack of an effective thermal stress dispersion mechanism. When the temperature changes drastically, the thermal expansion of different parts of the brick is inconsistent, and the instantaneous thermal stress cannot be released in time. The cracks will expand rapidly, leading to the brick peeling and damage. Utility Model Content

[0005] In order to overcome the problems and defects in the prior art, this utility model provides a thermal shock refractory brick reinforced with built-in ceramic fibers to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a thermal shock refractory brick reinforced with built-in ceramic fiber, comprising a refractory brick body, wherein the refractory brick body comprises, from the outside to the inside, an outer refractory layer, a ceramic fiber reinforcement layer and an inner refractory layer, wherein the outer refractory layer and the inner refractory layer are a mixture of high-purity high-alumina bauxite clinker and high-quality mullite powder.

[0007] The sum of the thicknesses of the outer and inner refractory layers accounts for 65%-75% of the total thickness of the refractory brick, and the thickness of the ceramic fiber reinforced layer accounts for 25%-35% of the total thickness of the refractory brick.

[0008] Preferably, the aluminosilicate ceramic fibers in the ceramic fiber reinforcement layer are distributed in a three-dimensional interlocking network, with a fiber diameter of 2-3 μm and a length of 6-9 mm. Furthermore, the ceramic fiber density is higher in the region near the outer and inner refractory layers than in the middle region, forming an adaptive gradient distribution.

[0009] Preferably, the surface of the ceramic fiber reinforcement layer is subjected to nanoscale modification treatment.

[0010] Preferably, a first nanocomposite transition buffer layer is provided between the ceramic fiber reinforced layer and the inner refractory layer, and a second nanocomposite transition buffer layer is provided between the ceramic fiber reinforced layer and the outer refractory layer.

[0011] Preferably, the first nanocomposite transition buffer layer and the second nanocomposite transition buffer layer are both composed of nanoscale refractory powder and a polymer elastomer with shape memory function, wherein the polymer elastomer with shape memory function is shape memory epoxy resin.

[0012] Preferably, the refractory brick body has multiple interconnected micropores inside, each with a pore diameter of 1-5 μm, and the pore diameter gradually increases from the outer layer to the inner layer.

[0013] Preferably, a connecting block is fixedly provided on the top of the refractory brick body, and a connecting groove is provided on the bottom surface of the refractory brick body. The connecting block and the connecting groove are movably engaged, and the cross-sectional shape of both the connecting block and the connecting groove is set to trapezoidal.

[0014] The technical effects and advantages of this utility model are as follows:

[0015] 1. Through the combined action of the outer refractory layer, the inner refractory layer, and the ceramic fiber reinforcement layer, the damage of thermal stress to the brick structure is effectively reduced; the three-dimensional interlocking network structure and adaptive gradient distribution of aluminosilicate ceramic fibers in the ceramic fiber reinforcement layer can disperse thermal stress in all directions, prevent the generation and propagation of cracks, and the high-density fiber area preferentially absorbs and buffers high thermal stress, while the low-density area regulates the stress distribution, ensuring that the refractory brick has high refractoriness and high strength, and can withstand high temperature environment and mechanical load;

[0016] 2. Through the first and second nanocomposite transition buffer layers, reversible deformation occurs under stress, absorbing and buffering thermal stress, reducing stress concentration at the interface. The gradient diameter structure of the micro-connected pores prevents rapid crack propagation with small pores on the outer layer and releases thermal stress with large pores on the inner layer. At the same time, the static air in the micro-connected pores forms a thermal insulation barrier, reducing the thermal conductivity, enhancing thermal insulation performance, and reducing heat transfer. The connecting block at the top and the connecting slot at the bottom of the refractory brick body adopt a trapezoidal movable snap-fit ​​design, realizing rapid and stable splicing between refractory bricks. Under high temperature and thermal shock environments, it can ensure tight connection of bricks and prevent structural instability and heat leakage. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0018] Figure 2 This is a schematic diagram of the structure of the refractory brick body of this utility model.

[0019] Figure 3 This is a schematic diagram of the internal structure of the refractory brick body of this utility model.

[0020] Figure 4 This is a schematic diagram of the internal microscopic interconnected pore structure of the refractory brick body of this utility model.

[0021] The attached figures are labeled as follows: 1. Refractory brick body; 2. Outer refractory layer; 3. Ceramic fiber reinforced layer; 4. Inner refractory layer; 5. First nanocomposite transition buffer layer; 6. Second nanocomposite transition buffer layer; 7. Microscopic interconnected pores; 8. Connecting block; 9. Connecting slot. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] As attached Figure 1-4 The refractory brick shown is a thermal shock resistant brick reinforced with built-in ceramic fiber, including a refractory brick body 1. The refractory brick body 1 includes an outer refractory layer 2, a ceramic fiber reinforcement layer 3 and an inner refractory layer 4 from the outside to the inside. The outer refractory layer 2 and the inner refractory layer 4 are made of a mixture of high-purity high-alumina bauxite clinker and high-quality mullite powder.

[0024] The combined thickness of the outer refractory layer 2 and the inner refractory layer 4 accounts for 65%-75% of the total thickness of the refractory brick, and the thickness of the ceramic fiber reinforced layer 3 accounts for 25%-35% of the total thickness of the refractory brick.

[0025] As attached Figure 3 As shown, the aluminosilicate ceramic fibers in the ceramic fiber reinforced layer 3 are distributed in a three-dimensional interlocking network. The fiber diameter is 2-3 μm and the length is 6-9 mm. In the region near the outer refractory layer 2 and the inner refractory layer 4, the ceramic fiber density is higher than that in the middle region, forming an adaptive gradient distribution. The surface of the ceramic fiber reinforced layer 3 is modified at the nanoscale to improve its thermal shock resistance.

[0026] As attached Figure 3 As shown, a first nanocomposite transition buffer layer 5 is provided between the ceramic fiber reinforced layer 3 and the inner refractory layer 4, and a second nanocomposite transition buffer layer 6 is provided between the ceramic fiber reinforced layer 3 and the outer refractory layer 2. Both the first nanocomposite transition buffer layer 5 and the second nanocomposite transition buffer layer 6 are composed of nano-scale refractory powder and a polymer elastomer with shape memory function. The polymer elastomer with shape memory function is shape memory epoxy resin, which can absorb and buffer thermal stress and reduce stress concentration at the interface.

[0027] As attached Figure 4 As shown, the refractory brick body 1 has multiple micro-connected pores 7 inside. The diameter of each micro-connected pore 7 is 1-5μm, and the pore diameter gradually increases from the outer layer to the inner layer. The small pores on the outer layer of the micro-connected pores 7 prevent the rapid propagation of cracks, while the large pores on the inner layer release thermal stress.

[0028] As attached Figure 1-4 As shown, a connecting block 8 is fixedly installed on the top of the refractory brick body 1, and a connecting slot 9 is opened on the bottom surface of the refractory brick body 1. The connecting block 8 and the connecting slot 9 are movably engaged. The cross-sectional shape of the connecting block 8 and the connecting slot 9 are both set as trapezoidal, which facilitates the stable splicing between the two refractory brick bodies 1. Under high temperature and thermal shock environment, the brick body can be tightly connected.

[0029] The working principle of this utility model is as follows: The outer refractory layer 2, with its high refractoriness and high strength, directly withstands the external high temperature environment and mechanical load, forming the first line of defense against high temperature erosion and mechanical wear of the refractory brick. The ceramic fiber reinforcement layer 3 is located in the middle core position. When the refractory brick is subjected to thermal shock, the thermal stress generated by the outer refractory layer 2 and the inner refractory layer 4 is transferred to the ceramic fiber reinforcement layer 3. The three-layer structure works together to buffer and disperse thermal stress, reducing the damage of thermal stress to the overall structure of the refractory brick.

[0030] When thermal stress is transferred to the ceramic fiber reinforced layer 3, the three-dimensional interlocking network structure acts like an elastic network. With the flexibility and interwoven characteristics of the fibers, it disperses thermal stress in all directions, preventing cracks from being generated and propagating. The adaptive gradient distribution allows the high-density fiber areas near the outer refractory layer 2 and the inner refractory layer 4 to preferentially absorb and buffer greater thermal stress, while the low-density areas in the middle further adjust the stress distribution while ensuring the overall structural strength, achieving efficient dispersion and relief of thermal stress. At the same time, the surface of the ceramic fiber reinforced layer 3 is modified at the nanoscale, which enhances the bonding force between the fibers and the matrix, ensuring that the fibers will not fall off during thermal shock and continue to play a reinforcing role.

[0031] Due to the difference in thermal expansion coefficients between the outer refractory layer 2, the inner refractory layer 4, and the ceramic fiber reinforced layer 3, stress concentration is easily generated at the interface during thermal shock. At this time, the first nanocomposite transition buffer layer 5 and the second nanocomposite transition buffer layer 6, made of shape memory epoxy resin, undergo reversible deformation under stress due to their unique shape memory characteristics, absorbing and buffering thermal stress. The nano-scale refractory powder ensures the refractory performance of the interface. The two work together to effectively reduce stress concentration at the interface and enhance the bonding strength and collaborative working ability between the layers.

[0032] During thermal shock, the smaller pores in the outer layer act as tiny stress buffer units, effectively preventing the rapid propagation of cracks and limiting the crack propagation path. The larger pores in the inner layer provide ample space for the release of thermal stress, allowing the thermal stress to be alleviated through the deformation of the pores and the buffering effect of the air. At the same time, the static air in these interconnected pores has low thermal conductivity, forming a thermal insulation barrier, reducing the thermal conductivity of the refractory brick, enhancing its thermal insulation performance, reducing heat transfer, and reducing the impact of thermal shock on the refractory brick.

[0033] The connecting block 8 at the top of the refractory brick body 1 and the connecting groove 9 at the bottom have a trapezoidal cross-section and are movably engaged. In practical applications, this connection structure can achieve rapid and stable splicing between refractory bricks. On the one hand, it ensures that the connection between refractory bricks is tight under high temperature and thermal shock environments, avoiding structural instability and heat leakage caused by loose connections. On the other hand, when a refractory brick is subjected to thermal shock and undergoes slight deformation, the trapezoidal engagement structure can adjust through a certain elastic deformation to prevent stress concentration at the connection point, further enhancing the thermal shock resistance and stability of the overall structure.

[0034] In conclusion, the above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A thermal shock resistant refractory brick reinforced with built-in ceramic fibers, comprising a refractory brick body (1), characterized in that: The refractory brick body (1) includes an outer refractory layer (2), a ceramic fiber reinforcement layer (3) and an inner refractory layer (4) from the outside to the inside. The outer refractory layer (2) and the inner refractory layer (4) are a mixture of high-purity high-alumina bauxite clinker and high-quality mullite powder. The sum of the thicknesses of the outer refractory layer (2) and the inner refractory layer (4) accounts for 65%-75% of the total thickness of the refractory brick, and the thickness of the ceramic fiber reinforced layer (3) accounts for 25%-35% of the total thickness of the refractory brick.

2. The thermal shock refractory brick reinforced with built-in ceramic fibers according to claim 1, characterized in that: The aluminosilicate ceramic fibers in the ceramic fiber reinforcement layer (3) are distributed in a three-dimensional interlocking network. The fiber diameter is 2-3 μm and the length is 6-9 mm. In the region near the outer refractory layer (2) and the inner refractory layer (4), the ceramic fiber density is higher than that in the middle region, forming an adaptive gradient distribution.

3. The thermal shock refractory brick reinforced with built-in ceramic fibers according to claim 1, characterized in that: The surface of the ceramic fiber reinforced layer (3) is modified at the nanoscale.

4. The thermal shock refractory brick reinforced with built-in ceramic fibers according to claim 1, characterized in that: A first nanocomposite transition buffer layer (5) is provided between the ceramic fiber reinforced layer (3) and the inner refractory layer (4), and a second nanocomposite transition buffer layer (6) is provided between the ceramic fiber reinforced layer (3) and the outer refractory layer (2).

5. The thermal shock refractory brick reinforced with built-in ceramic fiber according to claim 4, characterized in that: The first nanocomposite transition buffer layer (5) and the second nanocomposite transition buffer layer (6) are both composed of nano-scale refractory powder and a polymer elastomer with shape memory function. The polymer elastomer with shape memory function is shape memory epoxy resin.

6. The thermal shock refractory brick reinforced with built-in ceramic fibers according to claim 1, characterized in that: The refractory brick body (1) has multiple micro-connected pores (7) inside. The diameter of each micro-connected pore (7) is 1-5μm, and the pore diameter gradually increases from the outer layer to the inner layer.

7. The thermal shock refractory brick reinforced with built-in ceramic fibers according to claim 1, characterized in that: A connecting block (8) is fixedly provided on the top of the refractory brick body (1), and a connecting slot (9) is provided on the bottom surface of the refractory brick body (1). The connecting block (8) and the connecting slot (9) are movably engaged. The cross-sectional shape of the connecting block (8) and the connecting slot (9) is set as trapezoidal.

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