Lightweight high-performance tough fiber-reinforced calcium silicate board and production method thereof

Abstract

The invention discloses a lightweight high-performance tough fiber reinforced calcium silicate board, which comprises a siliceous material, a calcareous material, a multistage fiber reinforced system, a lightweight functional filler, a foaming agent and water, the multistage fiber comprises polyacrylonitrile-based carbon fiber, ultra-high molecular weight polyethylene fiber and surface modified PVA fiber, and the fibers are distributed in a surface high-strength layer and a core toughening layer in the plate. The surface layer mainly comprises carbon fibers to form a high-strength layer, and the core layer mainly comprises polyethylene and PVA fibers to form a toughening layer; the light functional filler comprises hollow glass beads and nano silicon dioxide aerogel powder. A'carbon fiber (rigid) + PE fiber (tough) + PVA fiber (bridging) 'multi-stage synergistic reinforcement system is initiated, and performance space optimization is realized through differentiated design of components of the surface layer and the core layer.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building decoration materials, in particular to a lightweight high-performance tough fiber reinforced calcium silicate board and a production method thereof. BACKGROUND

[0002] Decorative floor is an indispensable decoration material in the decoration process, laying floor not only improves the comfort when walking, but also can play a beautiful effect through the interlocking of floor with decorative patterns. As a kind of decorative floor, calcium silicate board is widely used.

[0003] However, the traditional calcium silicate board has the following defects: (1) lightweight and toughness contradiction: the bending strength and toughness decrease significantly when the density is reduced; (2) low fiber utilization efficiency: single fiber reinforcement is prone to interface defects, and the fiber pull-out effect is weak; (3) high energy consumption of production process: long high-temperature and high-pressure curing time and high cost. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a lightweight high-performance tough fiber reinforced calcium silicate board and a production method thereof, to solve the problems of lightweight and toughness contradiction, low fiber utilization efficiency and high energy consumption of production process of the current calcium silicate board.

[0005] To solve the above technical problems, the present application provides the following technical solutions:

[0006] A lightweight high-performance tough fiber reinforced calcium silicate board, comprising siliceous material, calcareous material, multi-stage fiber reinforcement system, lightweight functional filler, foaming agent and water, the multi-stage fiber comprises polyacrylonitrile-based carbon fiber (length 3-6mm, diameter 7-10um), ultra-high molecular weight polyethylene fiber (length 6-12mm, diameter 15-25um) and surface modified PVA fiber (length 8-15mm, surface treated with silane coupling agent), and the fibers are distributed in the form of surface high-strength layer and core toughening layer in the board. The surface layer mainly forms a high-strength layer with carbon fibers, and the core layer mainly forms a toughening layer with polyethylene and PVA fibers; the lightweight functional filler comprises hollow glass microbeads (particle size 20-50um, wall thickness 1-2um) and nano-silica aerogel powder.

[0007] The components are as follows in terms of weight parts:

[0008] Siliceous material: quartz powder or silica fume, 40-60 parts;

[0009] Calcareous material: slaked lime or cement, 20-35 parts;

[0010] Multi-level fiber reinforced system: polyacrylonitrile-based carbon fiber 0.5-1.5 parts, ultra-high molecular weight polyethylene fiber 1.0-2.0 parts, surface modified PVA fiber 0.5-1.5 parts;

[0011] Light functional filler: hollow glass microsphere 5-15 parts, nano-silica aerogel powder 2-8 parts;

[0012] Foaming agent: hydrogen peroxide or aluminum powder 0.1-0.5 parts

[0013] Water: solid-liquid ratio 0.28-0.35.

[0014] The application also provides a production method of lightweight high-performance tough fiber reinforced calcium silicate board, comprising the following steps:

[0015] Step one: fiber pretreatment

[0016] Polyacrylonitrile-based carbon fiber is coated with nano-SiO2 sol after oxidation by concentrated nitric acid, and the interface transition zone is thickened;

[0017] Surface modified PVA fiber is soaked in KH550 silane coupling agent ethanol solution;

[0018] Step two: gradient mixing

[0019] The surface layer slurry is prepared in a split body, the high silicon-calcium ratio is 1.2-1.5, and the full amount of polyacrylonitrile-based carbon fiber; the core layer slurry, the silicon-calcium ratio is 0.8-1.0, and the full amount of ultra-high molecular weight polyethylene fiber and surface modified PVA fiber;

[0020] Step three: dynamic pressure forming

[0021] The core layer slurry is first injected into the special mold, the surface layer slurry is injected after vibration degassing, and multi-stage gradient pressure is adopted to form the slab;

[0022] Step four: low temperature rapid setting and curing

[0023] First, the slab is preheated by microwave, then the slab is sent to the curing room for steam curing, and finally the slab is dried by hot air circulation to form the finished product.

[0024] Preferably, in step four, when preheating by microwave, the slab is irradiated with 700-850W for 3-5min, so that the temperature of the slab reaches 60-70℃; when steam curing, the slab is cured in 0.8-1.0MPa saturated steam for 4-6 hours; when drying, the slab is dried by hot air circulation at 70-90℃ until the moisture content is ≤5%.

[0025] Preferably, the special mold includes a box body, the lower part of the box body is fixedly connected to a forming basin, the bottom of the forming basin is a microporous air filter bottom plate, the bottom of the microporous air filter bottom plate is installed with a straight vibrator, a box body is slidably arranged in the box body, the outer wall of the box body is connected with a sealing strip, the sealing strip is in close contact with the inner wall of the box body, the top of the box body is connected with a connecting column, the two sides of the bottom of the box body are hinged with pressure plates, the opposite ends of the two pressure plates are in contact, an oil cylinder is installed on the top of the box body, the telescopic end of the oil cylinder extends into the box body and is connected to the connecting column, the box body can be driven into the forming basin by the extension of the oil cylinder, after the box body enters the forming basin, the sealing strip is in close contact with the inner wall of the forming basin, electric telescopic rods are installed at both ends of the top of the box body, the telescopic ends of the two electric telescopic rods extend to The box body is provided with a supporting plate, and the extending end is connected to the two pressure plates. The two pressure plates can be driven to deflect downward by extending the two electric telescopic rods. A feed pipe connected to the box body is provided in the connecting column, and the inner end of the feed pipe is connected to a main pipe arranged along the length direction of the box body. The two ends of the main pipe are connected to branch pipes. The two branch pipes are respectively located above the two pressure plates. The top of the box body is connected to a first injection pipe, and the inner end of the first injection pipe is connected to a hose. The hose is connected to the feed pipe. A second injection pipe is connected to the box body above the microporous air filter bottom plate, and the second injection pipe is connected to the forming basin. An exhaust pipe is connected to the box body below the microporous air filter bottom plate, and the exhaust pipe is connected to a vacuum pump. The bottom of the box body is connected to a sewage pipe. The front side of the box body is hinged with a door panel, and a sealing ring is provided around the door panel.

[0026] Preferably, the exhaust pipe and the sewage pipe are both provided with control valves, which are used to control the opening and closing of the exhaust pipe and the sewage pipe.

[0027] Preferably, the housing has a retractable bellows fixedly connected to both sides of the electric telescopic rod, with the lower ends of the bellows fixedly connected to the pressure plate. Because the bellows are elastic, they can be pulled against the bellows when the pressure plate rotates downward without breaking them. Furthermore, the bellows prevent slurry from penetrating the electric telescopic rod.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The first-of-its-kind "carbon fiber (rigid) + PE fiber (tough) + PVA fiber (bridging)" multi-level synergistic reinforcement system achieves performance space optimization through differentiated design of surface and core layer components.

[0030] Dynamic gradient pressurization technology: breaks through the traditional constant pressure mode and uses pressure relief and re-pressurization to eliminate interface defects.

[0031] Microwave-steam synergistic curing: Microwaves stimulate early hydration, shorten the formation time of tobermorite crystals, shorten the curing time, and reduce overall energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1Process flow chart of the present application;

[0033] Figure 2 Schematic diagram of the special mold;

[0034] In the figure: 1-box, 2-micro-porous filter bottom plate, 3-straight vibrator, 4-box, 5-sealing rubber strip, 6-connection column, 7-pressing plate, 8-oil cylinder, 9-electric telescopic rod, 10-feeding pipe, 11-main pipe, 12-branch pipe, 13-first feeding pipe, 14-second feeding pipe, 15-exhaust pipe, 16-vacuum pump, 17-drain pipe, 18-control valve, 19-molding basin, 20-hose, 21-corrugated cover. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0036] Embodiment 1

[0037] A lightweight high-performance strong and tough fiber reinforced calcium silicate board, comprising siliceous material, calcareous material, multi-level fiber reinforcement system, lightweight functional filler, foaming agent and water, the multi-level fiber comprises polyacrylonitrile-based carbon fiber, ultra-high molecular weight polyethylene fiber and surface modified PVA fiber, and the fibers are distributed in the board as a surface high-strength layer and a core toughening layer. The surface layer mainly forms a high-strength layer with carbon fibers, and the core layer mainly forms a toughening layer with polyethylene and PVA fibers; the lightweight functional filler comprises hollow glass microspheres and nano-silica aerogel powder.

[0038] The components are as follows in parts by weight:

[0039] Surface layer slurry: silica fume 50 parts, cement 25 parts, polyacrylonitrile-based carbon fiber 1.2 parts, hollow glass microspheres 10 parts, hydrogen peroxide 0.3 parts;

[0040] Core layer slurry: quartz powder 45 parts, slaked lime 30 parts, ultra-high molecular weight polyethylene fiber 1.8 parts, surface modified PVA fiber 1.0 part, hydrogen peroxide 0.3 parts.

[0041] The production method of the lightweight high-performance strong and tough fiber reinforced calcium silicate board comprises the following steps:

[0042] Step one: fiber pretreatment

[0043] The polyacrylonitrile-based carbon fiber is coated with nano-SiO2 sol after being oxidized by concentrated nitric acid to thicken the interface transition zone;

[0044] Surface modified PVA fiber soaked in KH550 silane coupling agent ethanol solution;

[0045] Step two: gradient mixing

[0046] Separate preparation: surface layer slurry, high silicon-calcium ratio 1.2-1.5, full amount of polyacrylonitrile-based carbon fiber; core layer slurry, silicon-calcium ratio 0.8-1.0, full amount of ultra-high molecular weight polyethylene fiber and surface modified PVA fiber;

[0047] Step three: dynamic pressure forming

[0048] First inject the core layer slurry in the special mold, then inject the surface layer slurry after vibration degassing, and use multi-stage gradient pressure to form the slab; when dynamic pressure is performed, the following sequence is performed: 0→1.5 MPa pressure for 20 s→depressurization to 0.3 MPa for 5 s→rise to 4 MPa for 50 s→pressure maintaining for 100 s;

[0049] Step four: low temperature rapid setting curing

[0050] First preheat the slab by microwave, irradiate for 3 min at 800 W, so that the slab temperature reaches 60℃; then send the slab to the curing room for steam curing, and cure in 0.8 MPa saturated steam for 4 hours; finally, dry the slab by hot air circulation, dry at 80℃ hot air circulation until the water content is ≤5%, to form the finished product.

[0051] Table 1, performance test of example 1

[0052]

[0053]

[0054] Example 2

[0055] A lightweight high-performance tough fiber reinforced calcium silicate board, comprising siliceous material, calcareous material, multi-level fiber reinforcement system, lightweight functional filler, foaming agent and water, the multi-level fiber comprises polyacrylonitrile-based carbon fiber, ultra-high molecular weight polyethylene fiber and surface modified PVA fiber, and the fibers are distributed in the board as a surface layer high strength layer and a core layer toughening layer. The surface layer mainly forms a high strength layer with carbon fiber, and the core layer mainly forms a toughening layer with polyethylene and PVA fiber; the lightweight functional filler comprises hollow glass microbeads and nano silica aerogel powder.

[0056] The components are as follows in parts by weight:

[0057] Surface layer slurry: quartz powder 55 parts, cement 20 parts, polyacrylonitrile-based carbon fiber 0.8 parts, hollow glass microbeads 12 parts, nano silica aerogel powder 3 parts, hydrogen peroxide 0.3 parts;

[0058] Core layer slurry: 40 parts of silica fume, 35 parts of slaked lime, 1.5 parts of ultra-high molecular weight polyethylene fiber, 0.8 parts of surface-modified PVA fiber, 8 parts of hollow glass microspheres, 4 parts of nano-silica aerogel powder, and 0.3 parts of hydrogen peroxide.

[0059] The production method of the light-weight, high-performance, strong fiber-reinforced calcium silicate board comprises the following steps:

[0060] Step 1: Fiber pretreatment

[0061] Polyacrylonitrile-based carbon fibers were oxidized with concentrated nitric acid and then coated with nano-SiO2 sol to thicken the interface transition zone;

[0062] Surface-modified PVA fibers were immersed in KH550 silane coupling agent ethanol solution;

[0063] Step 2: Gradient mixing

[0064] Separate preparation: surface layer slurry, high silicon-calcium ratio 1.2-1.5, polyacrylonitrile-based carbon fiber full amount; core layer slurry, silicon-calcium ratio 0.8-1.0, ultra-high molecular weight polyethylene fiber and surface-modified PVA fiber full amount;

[0065] Step 3: Dynamic pressure molding

[0066] The core layer slurry is first injected into a special mold, and the surface layer slurry is injected after vibration degassing. Multi-stage gradient pressurization is used to form the slab. When performing dynamic pressurization, the following sequence is followed: 0 → 1.8MPa pressurization for 25s → unloading pressure to 0.3MPa and holding for 8s → increasing pressure to 4.5MPa and pressurizing for 55s → holding pressure for 110s;

[0067] Step 4: Low temperature rapid setting and curing

[0068] The slab is first preheated by microwave, irradiated with 750W for 4 minutes to bring the slab temperature to 65°C; then the slab is sent to the curing room for steam curing, and cured in 0.9MPa saturated steam for 5 hours; finally, the slab is dried by hot air circulation at 75°C until the moisture content is ≤5%, forming a finished product.

[0069] Table 2, performance test of Example 2

[0070] Test item Measured value Density 0.89 g / cm 3 ]] Bending strength 23.5 MPa Fracture toughness <![CDATA[2.6MPa·m 1 / 2 ]]>

[0071] Example 3

[0072] A lightweight high-performance strong and tough fiber reinforced calcium silicate board, comprising siliceous material, calcareous material, multi-level fiber reinforcement system, lightweight functional filler, foaming agent and water, the multi-level fiber comprising polyacrylonitrile-based carbon fiber, ultra-high molecular weight polyethylene fiber and surface modified PVA fiber, and the fibers are distributed in the board as a surface high-strength layer and a core layer toughening layer. The surface layer is mainly carbon fiber to form a high-strength layer, and the core layer is mainly polyethylene and PVA fiber to form a toughening layer; the lightweight functional filler comprises hollow glass microbeads and nano-silica aerogel powder.

[0073] The components are as follows in parts by weight:

[0074] Surface layer slurry: silica ash 60 parts, cement 30 parts, polyacrylonitrile-based carbon fiber 1.5 parts, hollow glass microbeads 8 parts, nano-silica aerogel powder 6 parts, aluminum powder foaming agent 0.2 parts;

[0075] Core layer slurry: quartz powder 50 parts, slaked lime 25 parts, ultra-high molecular weight polyethylene fiber 2.2 parts, surface modified PVA fiber 1.5 parts, hollow glass microbeads 6 parts, nano-silica aerogel powder 7 parts, aluminum powder foaming agent 0.2 parts.

[0076] The production method of the lightweight high-performance strong and tough fiber reinforced calcium silicate board comprises the following steps:

[0077] Step one: fiber pretreatment

[0078] The polyacrylonitrile-based carbon fiber is coated with nano-SiO2 sol after oxidation with concentrated nitric acid to thicken the interface transition zone;

[0079] The surface modified PVA fiber is soaked in a KH550 silane coupling agent ethanol solution;

[0080] Step two: gradient mixing

[0081] Separate preparation: surface layer slurry, high silicon-calcium ratio 1.2-1.5, full amount of polyacrylonitrile-based carbon fiber; core layer slurry, silicon-calcium ratio 0.8-1.0, full amount of ultra-high molecular weight polyethylene fiber and surface modified PVA fiber;

[0082] Step three: dynamic pressure forming

[0083] The core layer slurry is first injected into a special mold, the surface layer slurry is injected after vibration degassing, and a multi-stage gradient pressure is adopted to form a board blank; during dynamic pressure, the following sequence is adopted: 0→2.2MPa pressure for 35s→decompression to 0.6MPa for 12s→rise to 5.8MPa for 65s→pressure maintaining for 148s;

[0084] Step four: low-temperature rapid-setting curing

[0085] First, the slab is preheated by microwave, irradiated for 5 min at 850 W, so that the temperature of the slab reaches 72°C; then the slab is sent to the curing chamber for steam curing, cured in 1.0 MPa saturated steam for 4.5 hours; finally, the slab is dried by hot air circulation, dried by 90°C hot air circulation until the moisture content is ≤5%, forming the finished product.

[0086] Table 3, performance test of Example 3

[0087] Test item Measured value Density 1.05 g / cm 3 ]] Bending strength 35.2 MPa Fracture toughness 4.1 MPa-m 1 / 2 ]]

[0088] Table 4, comparative analysis of each example

[0089] Performance index Example 1 Example 2 Example 3 Conventional calcium silicate board Density (g / cm 3 )]]> 0.95 0.89 1.05 1.2-1.4 Bending strength (MPa) 28.7 23.5 35.2 8-12 Fracture toughness MPa-m 1 / 2 ]] 3.1 2.6 0.5- 0.5-0.8

[0090] From Table 4, we can see that:

[0091] Lightweight: the density of Example 2 is reduced by 26% (compared with traditional boards), and still maintains more than 2 times the strength.

[0092] Toughening: the impact work of Example 3 is 6 times that of traditional boards, achieving a synergistic improvement in "strength-toughness".

[0093] Example 4

[0094] As Figure 2As shown, a special mold used in the production process of a lightweight high-performance tough fiber reinforced calcium silicate board, the special mold includes a box body 1, the lower part of the box body 1 is fixedly connected with a forming basin 19, the bottom of the forming basin 19 is a microporous gas filter bottom plate 2, the bottom of the microporous gas filter bottom plate 2 is provided with a straight vibrator 3, a box body 4 is slidingly arranged in the box body 1, the outer wall of the box body 4 is connected with a sealing rubber strip 5, the sealing rubber strip 5 is in close contact with the inner wall of the box body 1, the top of the box body 4 is connected with a connecting column 6, the two sides of the bottom of the box body 4 are hingedly connected with pressing plates 7, the opposite ends of the two pressing plates 7 are in contact, an oil cylinder 8 is installed on the top of the box body 1, the telescopic end of the oil cylinder 8 extends into the box body 1 and is connected with the connecting column 6, the extension of the oil cylinder can drive the box body into the forming basin, after the box body enters the forming basin, the sealing rubber strip 5 is in close contact with the inner wall of the forming basin, two electric telescopic rods 9 are installed at the two ends of the top of the box body, the telescopic ends of the two electric telescopic rods 9 extend into the box body 4 and are connected with the two pressing plates 7, the extension of the two electric telescopic rods 9 can drive the two pressing plates 7 to deflect downward, a feeding pipe 10 communicating with the box body 4 is arranged in the connecting column 6, the inner end of the feeding pipe 10 is connected with a main pipe 11 arranged along the length direction of the box body 4, the two ends of the main pipe 11 are connected with branch pipes 12, the two branch pipes 12 are respectively located above the two pressing plates 7, a first feeding pipe 13 is connected with the top of the box body 1, the inner end of the first feeding pipe 13 is connected with a hose 20, the hose 20 is connected with the feeding pipe 10, a second feeding pipe 14 is connected with the top of the box body 1 above the microporous gas filter bottom plate 2, the second feeding pipe is in communication with the forming basin, an exhaust pipe 15 is connected with the bottom of the box body 1 below the microporous gas filter bottom plate 2, a vacuum pump 16 is connected with the exhaust pipe 15, a sewage pipe 17 is connected with the bottom of the box body 1, a door plate is hingedly connected with the front side of the box body 1, and sealing rings are arranged around the door plate.

[0095] A control valve 18 is arranged on the exhaust pipe 15 and the sewage pipe 17. The control valve 18 is used to control the opening and closing of the exhaust pipe 15 and the sewage pipe 17.

[0096] A corrugated cover 21 with telescopic property is fixedly connected with the two sides of the electric telescopic rod in the box body 4, and the lower end of the corrugated cover 21 is fixedly connected with the pressing plate 7. Since the corrugated cover 21 has elasticity, when the pressing plate 7 rotates downward, the corrugated cover 21 can be pulled, and the corrugated cover 21 will not be torn off. At the same time, the arrangement of the corrugated cover 21 can prevent the slurry from penetrating into the electric telescopic rod 9.

[0097] The method for using the mold is as follows: the box door is closed, the sealing ring around the box door is in contact with the box body 1 to realize sealing, then the core layer slurry is injected into the forming basin 19 through the second injection pipe 14, then the oil cylinder 8 is controlled to extend to drive the box body 4 to descend, the sealing rubber strip 5 around the box body 4 is in close contact with the inner wall of the forming basin at all times after the box body 4 enters the forming basin 19, thereby playing a sealing role to prevent the slurry from penetrating upward. In addition, when the box body 4 descends, the slurry in the forming basin is extruded by the pressing plate 7 to realize pressurization, and gas is discharged by the microporous gas filtering bottom plate 2 during pressurization, when the core layer slurry is leveled in the forming basin 19, the oil cylinder 8 is retracted to drive the box body 4 to ascend, the vacuum pump 16 is started to extract the trapped micro-bubbles during the ascending stage of the box body 4, then the electric telescopic rod 9 is controlled to extend to deflect the pressing plate 7 downward by a certain angle, then the surface layer slurry is added into the box body through the first injection pipe 13, the surface layer slurry falls on the pressing plate 7 from the branch pipe 12 and flows downward along the inclined surface of the pressing plate 7 to be stably spread, thereby avoiding the surface layer slurry directly impacting the core layer slurry, until the surface layer slurry is spread in the forming basin, then the oil cylinder 8 is extended again to drive the box body 4 to descend to be pressurized again and maintain a certain pressure to form a slab. Then the box door is opened, and the slab can be taken out from the forming basin 19.

[0098] It should be noted that the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element preceded by "comprises... a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the recited element.

[0099] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A lightweight, high-performance, strong fiber-reinforced calcium silicate board, characterized by: The board comprises a siliceous material, a calcareous material, a multi-stage fiber reinforcement system, a lightweight functional filler, a foaming agent and water, wherein the multi-stage fiber comprises polyacrylonitrile-based carbon fiber, ultra-high molecular weight polyethylene fiber and surface-modified PVA fiber, and the fibers are distributed in the board as a surface high-strength layer and a core toughening layer; the lightweight functional filler comprises hollow glass microspheres (with a particle size of 20-50 μm and a wall thickness of 1-2 μm) and nano-silica aerogel powder; The components are calculated in parts by weight as follows: Silica material: quartz powder or silica fume, 40-60 parts; Calcium material: slaked lime or cement, 20-35 parts; Multi-stage fiber reinforcement system: 0.5-1.5 parts of polyacrylonitrile-based carbon fiber, 1.0-2.0 parts of ultra-high molecular weight polyethylene fiber, and 0.5-1.5 parts of surface-modified PVA fiber; Lightweight functional filler: 5-15 parts of hollow glass microspheres, 2-8 parts of nano-silica aerogel powder; Foaming agent: 0.1-0.5 parts of hydrogen peroxide or aluminum powder Water: solid-liquid ratio 0.28-0.

35.

2. The lightweight, high-performance, strong fiber-reinforced calcium silicate board according to claim 1, characterized in that: The surface layer is mainly composed of carbon fiber to form a high-strength layer, and the core layer is mainly composed of polyethylene and PVA fibers to form a toughening layer.

3. The lightweight, high-performance, strong fiber-reinforced calcium silicate board according to claim 2, characterized in that: The polyacrylonitrile-based carbon fiber has a length of 3-6 mm and a diameter of 7-10 μm; the ultra-high molecular weight polyethylene fiber has a length of 6-12 mm and a diameter of 15-25 μm; the surface-modified PVA fiber has a length of 8-15 mm and is surface-treated with a silane coupling agent.

4. The lightweight, high-performance, strong fiber-reinforced calcium silicate board according to claim 3, characterized in that: The hollow glass microspheres have a particle size of 20-50 μm and a wall thickness of 1-2 μm.

5. The method for producing a lightweight, high-performance, strong fiber-reinforced calcium silicate board according to claim 4, characterized in that: The following steps are involved: Step 1: Fiber pretreatment Polyacrylonitrile-based carbon fibers were oxidized with concentrated nitric acid and then coated with nano-SiO2 sol to thicken the interface transition zone; Surface-modified PVA fibers were immersed in KH550 silane coupling agent ethanol solution; Step 2: Gradient mixing Prepare the surface slurry separately, with a high silicon-calcium ratio of 1.2-1.5 and the full amount of polyacrylonitrile-based carbon fiber; the core slurry, with a silicon-calcium ratio of 0.8-1.0, and the full amount of ultra-high molecular weight polyethylene fiber and surface-modified PVA fiber; Step 3: Dynamic pressure molding The core layer slurry is first injected into a special mold, and the surface layer slurry is injected after vibration degassing. Multi-stage gradient pressurization is adopted to form a slab; Step 4: Low temperature rapid setting and curing The slab is first preheated by microwave, then sent to the curing room for steam curing, and finally dried by hot air circulation to form the finished product.

6. The method for producing a lightweight, high-performance, strong fiber-reinforced calcium silicate board according to claim 5, characterized in that: In step 4, during microwave preheating, the slab is irradiated with 700-850W for 3-5 minutes to make the slab temperature reach 60-70°C; during steam curing, it is cured in 0.8-1.0MPa saturated steam for 4-6 hours; during drying, the slab is dried by hot air circulation at 70-90°C until the moisture content is ≤5%.

7. The method for producing a lightweight, high-performance, strong fiber-reinforced calcium silicate board according to claim 6, characterized in that: The special mold comprises a box body (1), a molding basin (19) is fixedly connected to the lower part of the box body (1), the bottom of the molding basin (19) is a microporous air filter bottom plate (2), a straight vibrator (3) is installed at the bottom of the microporous air filter bottom plate (2), a box body (4) is slidably arranged in the box body (1), the outer wall of the box body (4) is connected to a sealing strip (5), the top of the box body (4) is connected to a connecting column (6), and the two sides of the bottom of the box body (4) are hinged with pressure plates (7), and the relative positions of the two pressure plates (7) are fixedly connected to the bottom of the box body (4). The ends of the boxes (1) are in contact with each other. A cylinder (8) is installed on the top of the box body (1). The telescopic end of the cylinder (8) extends into the box body (1) and is connected to the connecting column (6). The extension of the cylinder can drive the box body into the forming basin. After the box body enters the forming basin, the sealing strip (5) is in close contact with the inner wall of the forming basin. Electric telescopic rods (9) are installed at both ends of the top of the box body. The telescopic ends of the two electric telescopic rods (9) extend into the box body (4), and the extended ends are connected to the two pressing plates (7). The extension of the telescopic rod (9) can drive the two pressure plates (7) to deflect downward. A feed pipe (10) communicating with the box body (4) is provided in the connecting column (6). The inner end of the feed pipe (10) is connected to a main pipe (11) provided along the length direction of the box body (4). Both ends of the main pipe (11) are connected to branch pipes (12). The two branch pipes (12) are respectively located above the two pressure plates (7). The top of the box body (1) is connected to a first injection pipe (13). The inner end of the first injection pipe (13) is connected to a hose. (20), the hose (20) is connected to the feed pipe (10), a second injection pipe (14) is connected to the box body (1) above the microporous air filter bottom plate (2), the second injection pipe is communicated with the molding basin, an exhaust pipe (15) is connected to the box body (1) below the microporous air filter bottom plate (2), the exhaust pipe (15) is connected to a vacuum pump (16), the bottom of the box body (1) is connected to a sewage pipe (17), the front side of the box body (1) is hinged with a door panel, and a sealing ring is provided around the door panel.

8. The method for producing a lightweight, high-performance, strong fiber-reinforced calcium silicate board according to claim 7, characterized in that: The exhaust pipe (15) and the sewage pipe (17) are both provided with a control valve (18).

9. The method for producing a lightweight, high-performance, strong fiber-reinforced calcium silicate board according to claim 8, characterized in that: Inside the box body (4), two sides of the electric telescopic rod are fixedly connected with a telescopic bellows (21), and the lower end of the bellows (21) is fixedly connected to the pressing plate (7).

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