Charred wood multi-insulation layer composite floor and preparation method thereof

Abstract

The present application relates to the technical field of composite floor manufacturing, and particularly relates to a carbonized wood multi-insulation layer composite floor and a manufacturing method thereof, comprising: carbonizing wood blanks; obtaining a grid-shaped base material; sequentially laying a base fiberboard, a first grid-shaped base material, a stress absorption layer plate, a second grid-shaped base material and a carbonized wood surface layer in a sequence from bottom to top, and performing cold pressing to obtain a composite floor blank, wherein the cold pressing pressure is adjusted according to the interlayer contact resistance of the first grid-shaped base material, and the relative laying direction of the first grid-shaped base material and the second grid-shaped base material is determined according to the average moisture content and the moisture content distribution variance; preheating and pressing the composite floor blank; determining a step-down value of the hot pressing pressure of a stage-type step-down hot pressing mode according to a thickness change rate; and hot pressing the composite floor blank to obtain a finished product composite floor. The present application realizes the improvement of the performance stability of the composite floor.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite floor manufacturing, in particular to a carbonized wood multi-insulation layer composite floor and a manufacturing method thereof. BACKGROUND

[0002] In the prior art, the carbonized wood multi-insulation layer composite floor is a new type of composite floor combining carbonized wood material and multi-layer insulation structure. Its manufacturing method involves processes such as carbonization treatment, multi-layer structure laying, and hot-pressing forming. The carbonized wood material has excellent corrosion resistance, insect resistance, and moisture resistance after high-temperature carbonization treatment. However, the traditional carbonized wood floor is prone to poor dimensional stability due to uneven water content distribution during the manufacturing process, which affects the service life of the floor. The carbonized wood multi-insulation layer composite floor can be used as a home floor decoration material. Its low water content and corrosion resistance make it particularly suitable for humid environments, such as kitchens and bathrooms. It also has good sound insulation and impact resistance in commercial settings, making it suitable for high-traffic areas. Due to the weather resistance and insect resistance of carbonized wood material, it can also be applied to outdoor facilities, such as balconies, terraces, and wooden boardwalks, especially in humid or variable climate environments.

[0003] Chinese Patent Publication No. CN111173226A discloses a composite flame-retardant solid wood floor and its manufacturing process. The composite flame-retardant solid wood floor has a topcoat layer, a carbonized flame-retardant board layer one, a flame-retardant layer one, a solid wood flame-retardant board layer, a flame-retardant layer two, and a carbonized flame-retardant board layer two from top to bottom. The thickness ratio of the carbonized flame-retardant board layer one, the flame-retardant layer one, the solid wood flame-retardant board layer, the flame-retardant layer two, and the carbonized flame-retardant board layer two is 10-14:2.5-3.5:35-48:2.5-3.5:10-14. As can be seen, the composite flame-retardant solid wood floor and its manufacturing process have the problem that when the carbonized wood floor is applied in a geothermal environment, such as floor heating or areas with obvious dry-wet alternation, the response of the materials in each layer of the floor to temperature and humidity changes, i.e., the difference in expansion and contraction coefficients, leads to internal stress accumulation, which in turn causes the floor to warp, deform, crack, or crack at the joint. SUMMARY

[0004] Therefore, the present application provides a carbonized wood multi-insulation layer composite floor and a manufacturing method thereof to overcome the problem that when the carbonized wood floor is applied in a geothermal environment, such as floor heating or areas with obvious dry-wet alternation, the response of the materials in each layer of the floor to temperature and humidity changes, i.e., the difference in expansion and contraction coefficients, leads to internal stress accumulation, which in turn causes the floor to warp, deform, crack, or crack at the joint.

[0005] To achieve the above-mentioned purpose, the present application provides a manufacturing method of a carbonized wood multi-insulation layer composite floor, comprising:

[0006] carbonizing wood blanks to obtain a carbonized wood veneer, and detecting an average moisture content and a moisture content distribution variance of the carbonized wood veneer;

[0007] embedding an alloy barrier layer into a mold to obtain a mesh-like base material;

[0008] sequentially laying, in order from bottom to top, a base fiberboard, a first mesh-like base material, a stress absorption layer board, a second mesh-like base material, and the carbonized wood veneer, and cold-pressing according to a cold-pressing pressure to obtain a composite floor blank,

[0009] wherein the cold-pressing pressure of the cold-pressing process is adjusted according to an interlayer contact resistance of the first mesh-like base material, and a relative laying direction of the first mesh-like base material and the second mesh-like base material is determined according to the average moisture content and the moisture content distribution variance;

[0010] pre-heat-pressing the composite floor blank to obtain a thickness variation rate of the composite floor blank;

[0011] determining a step-down step value of a heat-pressing pressure of a step-down heat-pressing mode according to the thickness variation rate;

[0012] heat-pressing the composite floor blank according to the step-down heat-pressing mode to obtain a finished product composite floor.

[0013] Further, the process of determining the relative laying direction of the first mesh-like base material and the second mesh-like base material according to the average moisture content and the moisture content distribution variance comprises:

[0014] respectively obtaining the average moisture content and the moisture content distribution variance;

[0015] if the average moisture content is less than or equal to a preset moisture content and the moisture content distribution variance is less than or equal to a preset variance, laying the mesh main direction of the first mesh-like base material parallel to a long edge direction of the composite floor blank, and laying the mesh main direction of the second mesh-like base material perpendicular to the long edge direction of the composite floor blank;

[0016] if the average moisture content is greater than the preset moisture content and the moisture content distribution variance is less than or equal to the preset variance, laying the mesh main direction of the first mesh-like base material parallel to the long edge direction, and laying the mesh main direction of the second mesh-like base material at an acute angle with the long edge direction;

[0017] if the average moisture content is less than or equal to the preset moisture content and the moisture content distribution variance is greater than the preset variance, laying the mesh main direction of the first mesh-like base material and the mesh main direction of the second mesh-like base material at an oblique angle with the long edge direction, and the included angle between the mesh main direction of the first mesh-like base material and the mesh main direction of the second mesh-like base material is an acute angle.

[0018] If the average moisture content is greater than the preset moisture content and the moisture content distribution variance is greater than the preset variance, the grid main direction of the first grid-shaped substrate is laid at an acute angle with the long side direction, the grid main direction of the second grid-shaped substrate is laid at an acute angle with the long side direction, and the acute angle between the grid main direction of the first grid-shaped substrate and the long side direction is smaller than the acute angle between the grid main direction of the second grid-shaped substrate and the long side direction.

[0019] Further, the moisture content distribution variance is the average of the sum of squares of the differences between the moisture contents of the detection points on the surface of the carbonized wood veneer layer and the average moisture content.

[0020] Further, the surface of the carbonized wood veneer layer is divided into a plurality of detection areas according to a square per unit length, and the center point of the detection area is the detection point of the moisture content.

[0021] Further, the process of adjusting the cold pressing pressure of the cold pressing process according to the interlayer contact resistance of the first grid-shaped substrate comprises:

[0022] Obtaining the interlayer contact resistance of the first grid-shaped substrate during the cold pressing process;

[0023] Comparing the interlayer contact resistance with a preset resistance;

[0024] If the interlayer contact resistance collected for a plurality of times continuously is greater than or equal to the preset resistance, the cold pressing pressure is increased to the set value after the interlayer contact resistance decreases.

[0025] Further, the process of determining the step-down value of the heat pressing pressure of the stage-type heat pressing mode according to the thickness change rate comprises:

[0026] Obtaining the thickness change rate;

[0027] Comparing the thickness change rate with a preset change rate;

[0028] If the thickness change rate is greater than or equal to the preset change rate, the step-down value is reduced.

[0029] Further, the thickness change rate is the ratio of the difference between the thickness of the composite floor blank at the starting moment of the pre-heat pressing and the thickness of the composite floor blank at the ending moment of the pre-heat pressing to the thickness of the composite floor blank at the starting moment of the pre-heat pressing.

[0030] Further, the increase range of the cold pressing pressure is determined according to the difference between the maximum interlayer contact resistance collected continuously and the preset resistance.

[0031] Further, the down-regulation step value is the hot-pressing pressure at the last adjustment time minus the product of the down-regulation multiple and the hot-pressing pressure at the last adjustment time.

[0032] The present application provides a kind of carbonized wood multi-insulation layer composite floor, comprising:

[0033] From bottom to top, base fiberboard, first grid substrate, stress absorption layer plate, second grid substrate and carbonized wood surface layer are sequentially laid;

[0034] The thickness of the carbonized wood surface layer is 2-4mm;

[0035] The first grid substrate and the second grid substrate are respectively made of nickel-chromium alloy into net structure, grid aperture is 2-5mm, and wire diameter is 0.3-0.6mm;

[0036] The stress absorption layer plate is polyurethane elastomer layer, and the thickness is 1-2mm;

[0037] The base fiberboard is high-density fiberboard, and the thickness is 8-12mm.

[0038] Compared with the prior art, the beneficial effects of the present application are that the method detects the average moisture content and moisture content distribution variance of the carbonized wood surface layer by carbonizing wood billet to obtain carbonized wood surface layer, so as to realize the internal moisture state of the carbonized wood surface layer, the drier the surface layer, the greater the potential trend of hygroscopic expansion in the use environment, and the stronger the memory elastic force of its attempt to restore the original state, which may generate greater internal stress in subsequent processing. By embedding the alloy insulation layer into the mold to form the grid substrate, the internal stress generated by the shrinkage and expansion of the wood layer due to temperature and humidity changes is effectively offset by using the retraction force characteristics of the grid substrate after heating, thereby reducing the deformation risk of the overall composite floor. By sequentially laying the base fiberboard, the first grid substrate, the stress absorption layer plate, the second grid substrate and the carbonized wood surface layer in the order from bottom to top, and adjusting the cold-pressing pressure according to the interlayer contact resistance of the first grid substrate during cold-pressing, the dynamic control of the tightness of the composite layer is realized, and a good stress conduction path is formed between different material layers in the composite structure. By determining the relative laying direction of the first grid substrate and the second grid substrate according to the average moisture content and moisture content distribution variance of the carbonized wood surface layer, the composite structure has anisotropic adaptive ability, so that the structure can still remain stable when facing stress changes in different directions, and when the floor heating is turned on and the environmental temperature exceeds the phase transition temperature of the grid substrate, the grid substrate actively shrinks to apply pre-stress to the grid and tighten the floor structure, and actively resist the swelling trend of the surface layer caused by temperature rise.

[0039] Further, the method of the present application adjusts the relative laying direction of the first and second grid substrates under different conditions when the wood blank has reached or is below the equilibrium moisture content of the use environment, the possibility of future hygroexpansion is greater than that of drying shrinkage, and the internal moisture content of the wood is very uniform, so the overall deformation trend is small. At this time, by laying the grid main direction of the first grid substrate parallel to the long edge direction of the composite floor blank and laying the grid main direction of the second grid substrate perpendicular to the long edge direction of the composite floor blank, the two layers of grids provide the strongest constraint in the longitudinal and transverse directions of the board, respectively, forming an orthogonal grid reinforcement structure that uniformly resists the small stresses that may come from various directions, improving dimensional stability. When the wood blank is overall wet and will mainly undergo drying shrinkage in the future, but the shrinkage is uniform, mainly resisting the transverse shrinkage with the largest shrinkage rate along the grain direction of the wood, by laying the grid main direction of the first grid substrate parallel to the long edge direction and laying the grid main direction of the second grid substrate at an acute angle to the long edge direction to constrain the transverse shrinkage. When the wood blank has a suitable overall dryness but uneven internal dryness, resulting in a high risk of warping due to uneven expansion or complex internal shear stress in the future, by laying the grid main direction of the first grid substrate and the grid main direction of the second grid substrate at an oblique angle to the long edge direction, and the included angle between the grid main direction of the first grid substrate and the grid main direction of the second grid substrate is an acute angle, the uneven stress is dispersed in multiple directions, thereby inhibiting deformation caused by excessive local stress. When the wood blank is both wet and uneven, resulting in severe and uneven shrinkage in the future, which in turn produces shrinkage stress and shear stress causing cracking and warping, by laying the grid main direction of the first grid substrate at an acute angle to the long edge direction and laying the grid main direction of the second grid substrate at an acute angle to the long edge direction, and the acute angle between the grid main direction of the first grid substrate and the long edge direction is less than the acute angle between the grid main direction of the second grid substrate and the long edge direction, providing a relatively balanced constraint force in the longitudinal, transverse, and diagonal directions to cope with complex and severe stress changes, achieving improved stability of the performance of the composite floor.

[0040] Further, the method of the present application increases the cold pressing pressure. Since the humidity distribution of the template is uneven, the hygroscopic performance of the template under the condition of environmental humidity is uneven. By increasing the cold pressing pressure during cold pressing, the layers are firmly bonded and fixed to resist the problem of poor internal stress uniformity caused by uneven hygroscopic performance, thereby preventing interlayer peeling.

[0041] Further, the method of the present application obtains the thickness variation rate of the composite floor blank by preheating pressing, and determines the hot-pressing pressure step-down value of the stage-type hot-pressing mode according to the variation rate, so as to avoid uneven stress distribution in the composite structure caused by excessive or insufficient hot-pressing pressure; the cold-pressing pressure determines the initial density of the blank, and in the hot-pressing activation stage, the grid-shaped substrate shrinks under heat and does work, and the hot-pressing pressure restricts the shrinkage, so that the stress cannot be effectively released or even the structure is damaged and cannot effectively guide the shrinkage direction, resulting in the structure being skewed, and by subsequently gradually reducing the pressure, a gradual environment is provided for the shrinkage of the grid-shaped substrate, the shrinkage force of the grid-shaped substrate is directed to act on the overall structure, and the stability of the mechanical properties of the composite board is improved.

[0042] Further, the method of the present application ensures that the composite floor can fully release internal stress during the forming process, improves the bonding strength between material layers, and thus enhances the dimensional stability and durability in the geothermal environment.

[0043] Further, the composite floor of the present application is stacked from bottom to top by the base fiberboard, the first grid-shaped substrate, the stress absorption layer plate, the second grid-shaped substrate, and the carbonized wood surface layer, wherein the thickness of the carbonized wood surface layer is controlled to be 2-4 mm, so as to ensure that it has good carbonization stability; the first grid-shaped substrate and the second grid-shaped substrate are made of nickel-chromium alloy, and have good heat conduction performance and mechanical shrinkage characteristics; the stress absorption layer plate is made of polyurethane elastomer, and has good elasticity and stress buffering capacity, and can effectively absorb local stress generated due to the difference in material expansion and shrinkage; the base fiberboard is a high-density fiberboard, which provides support and stability for the overall structure. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 The figure is the overall flowchart of the preparation method of the carbonized wood multi-insulation layer composite floor of the embodiment of the present application;

[0045] Figure 2 The figure is the flowchart of determining the relative laying direction of the first grid-shaped substrate and the second grid-shaped substrate in the preparation method of the carbonized wood multi-insulation layer composite floor of the embodiment of the present application;

[0046] Figure 3 The figure is the flowchart of adjusting the cold-pressing pressure in the preparation method of the carbonized wood multi-insulation layer composite floor of the embodiment of the present application;

[0047] Figure 4 The figure is the structure schematic diagram of the carbonized wood multi-insulation layer composite floor of the embodiment of the present application;

[0048] Explanation of reference numerals: 1-base fiberboard, 2-first grid-shaped substrate, 3-stress absorption layer plate, 4-second grid-shaped substrate, 5-carbonized wood surface layer. Detailed Implementation

[0049] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0050] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0051] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0052] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0053] Please see Figure 1 , Figure 2 , Figure 3 as well as Figure 4 The diagrams shown are, respectively, an overall flowchart of the carbonized wood multi-insulation layer composite flooring and its preparation method according to an embodiment of the present invention, a flowchart for determining the relative laying direction of the first and second mesh substrates, a flowchart for adjusting the cold pressing pressure, and a structural schematic diagram of the carbonized wood multi-insulation layer composite flooring. The present invention provides a method for preparing carbonized wood multi-insulation layer composite flooring, comprising:

[0054] The wood blanks are carbonized to obtain a carbonized wood surface layer, and the average moisture content and moisture content distribution variance of the carbonized wood surface layer are detected.

[0055] An alloy insulating layer is embedded in a mold to obtain a mesh-like substrate;

[0056] The base fiberboard, the first mesh substrate, the stress-absorbing layer, the second mesh substrate, and the carbonized wood surface layer are laid in sequence from bottom to top, and then cold-pressed to obtain the composite flooring blank.

[0057] wherein a cold-pressing pressure of the cold-pressing process is adjusted according to an interlayer contact resistance of the first grid-shaped substrate, and a relative laying direction of the first grid-shaped substrate and the second grid-shaped substrate is determined according to the average moisture content and the moisture content distribution variance;

[0058] pre-heat pressing the composite floor blank to obtain a thickness variation rate of the composite floor blank;

[0059] determining a step-down value of the hot-pressing pressure of the step-down hot-pressing mode according to the thickness variation rate;

[0060] hot-pressing the composite floor blank according to the step-down hot-pressing mode to obtain a finished product composite floor.

[0061] Specifically, in the process of laying the base fiberboard, the first grid-shaped substrate, the stress absorption layer board, the second grid-shaped substrate and the carbonized wood surface layer in order from bottom to top, an adhesive needs to be added between each two adjacent layers of boards.

[0062] Specifically, the carbonization treatment conditions are as follows: the carbonization treatment temperature is in the range of [180℃, 220℃], the carbonization treatment time is in the range of [2 hours, 4 hours], and the oxygen concentration is less than 5%; under the conditions that the wood blank material is oak and the wood blank thickness is not more than 5cm, the preferred embodiment of the carbonization treatment temperature is 200℃, and the preferred embodiment of the carbonization treatment time is 3 hours.

[0063] Specifically, the carbonization treatment device is a reaction kettle, the laid materials are cold-pressed and bonded by a cold press, and the materials and the adhesive are cured by a hot press.

[0064] Specifically, the cold-pressing temperature is 24℃, and the pressure holding time after cold-pressing is 15min.

[0065] Under the condition that the adhesive is urea-formaldehyde resin glue, the hot-pressing temperature is 120℃, and the total hot-pressing time is in the range of [4min, 6min].

[0066] The actual hot-pressing total time, the actual cold-pressing temperature and the actual pressure holding time can be adjusted by the person skilled in the art according to the actual situation.

[0067] Specifically, the interlayer contact resistance is measured by setting electrodes on the upper and lower surfaces of the first grid-shaped substrate to measure the contact resistance between the first grid-shaped substrate and the adjacent layers.

[0068] Specifically, the moisture content is detected by a microwave moisture content detector, and the thickness of the composite floor blank is detected by a displacement sensor.

[0069] In the implementation, the method of the present application realizes the internal moisture state of the carbonized wood surface layer by carbonizing the wood blank to obtain the carbonized wood surface layer and detecting the average moisture content and the moisture content distribution variance, so that the drier the surface layer is, the greater the potential trend of moisture absorption expansion in the use environment is, and the stronger the memory elastic force of the surface layer trying to restore the original state is, which may generate greater internal stress in the subsequent processing. By embedding the alloy isolation layer into the mold to form the grid-shaped substrate, the internal stress generated by the shrinkage and expansion of the wood layer caused by the change of temperature and humidity is effectively offset by using the characteristic of the retraction force generated after heating, thereby reducing the deformation risk of the overall composite floor. By sequentially laying the base fiber board, the first grid-shaped substrate, the stress absorption layer plate, the second grid-shaped substrate and the carbonized wood surface layer in the order from bottom to top, and adjusting the cold pressing pressure according to the interlayer contact resistance of the first grid-shaped substrate during the cold pressing process, the dynamic control of the tightness of the composite interlayer is realized, and the composite structure is ensured to form a good stress conduction path between different material layers. By determining the relative laying direction of the first grid-shaped substrate and the second grid-shaped substrate according to the average moisture content and the moisture content distribution variance of the carbonized wood surface layer, the composite structure has anisotropic adaptive ability, so that the structure can still remain stable when facing stress changes in different directions, and when the floor heating is turned on and the environmental temperature exceeds the phase transition temperature of the grid-shaped substrate, the grid-shaped substrate actively shrinks to apply a prestress to the grid and then tightens the floor structure to actively resist the surface layer expansion trend caused by the temperature rise.

[0070] Specifically, the process of determining the laying rotation angle of the first grid-shaped substrate and the second grid-shaped substrate according to the average moisture content and the moisture content distribution variance includes:

[0071] respectively obtaining the average moisture content and the moisture content distribution variance;

[0072] if the average moisture content is less than or equal to a preset moisture content and the moisture content distribution variance is less than or equal to a preset variance, the main direction of the grid of the first grid-shaped substrate is laid parallel to the long edge direction of the composite floor blank, and the main direction of the grid of the second grid-shaped substrate is laid perpendicular to the long edge direction of the composite floor blank;

[0073] if the average moisture content is greater than the preset moisture content and the moisture content distribution variance is less than or equal to the preset variance, the main direction of the grid of the first grid-shaped substrate is laid parallel to the long edge direction, and the main direction of the grid of the second grid-shaped substrate is laid at an acute angle with the long edge direction;

[0074] if the average moisture content is less than or equal to the preset moisture content and the moisture content distribution variance is greater than the preset variance, the grid main direction of the first grid substrate and the grid main direction of the second grid substrate are laid at an oblique angle to the long side direction, and the included angle between the grid main direction of the first grid substrate and the long side direction is an acute angle;

[0075] if the average moisture content is greater than the preset moisture content and the moisture content distribution variance is greater than the preset variance, the grid main direction of the first grid substrate is laid at an acute angle to the long side direction, the grid main direction of the second grid substrate is laid at an acute angle to the long side direction, and the acute angle between the grid main direction of the first grid substrate and the long side direction is smaller than the acute angle between the grid main direction of the second grid substrate and the long side direction.

[0076] Specifically, the grid main direction is the main extension direction of the continuous wire bundle,

[0077] wherein, for a rectangular grid, the grid long side direction is taken as the grid main direction, and for a rhombic diagonal grid, the grid symmetry axis direction is taken as the grid main direction.

[0078] Specifically, in laying the grid main direction of the first grid substrate parallel to the long side direction and laying the grid main direction of the second grid substrate at an acute angle to the long side direction, the acute angle between the grid main direction of the second grid substrate and the long side direction is 45°;

[0079] In laying the grid main direction of the first grid substrate and the grid main direction of the second grid substrate at an oblique angle to the long side direction, the included angle between the grid main direction of the first grid substrate and the long side direction is 22.5°, and the included angle between the grid main direction of the second grid substrate and the long side direction is 67.5°;

[0080] In laying the grid main direction of the first grid substrate at an acute angle to the long side direction and laying the grid main direction of the second grid substrate at an acute angle to the long side direction, the included angle between the grid main direction of the first grid substrate and the long side direction is 30°, and the included angle between the grid main direction of the second grid substrate and the long side direction is 60°.

[0081] Specifically, under the conditions that the adhesive is urea-formaldehyde resin glue, the blank material is oak, and the length of the composite floor blank is not more than 2m, the preset moisture content is generally in the range of [5%, 9%], the preset variance is generally in the range of [1%, 2%], the preferred embodiment of the preset moisture content is 8%, and the preferred embodiment of the preset variance is 1.5%. 2 2 2

[0082] ​​​Those skilled in the art can understand that the optional range of the preset moisture content and the preset variance and the preferred embodiment provided in the embodiment are the values selected under the condition that the adhesive is urea-formaldehyde resin glue, the blank material is oak, and the length of the composite floor blank is not more than 2 m, and the values are the best values for the effect of the technical problem solved by the technical scheme of the present application. In actual application or experiment, those skilled in the art can adaptively adjust the preset moisture content and the preset variance according to the actual application environment and application scene.

[0083] Specifically, the variance of the moisture content distribution is the average value of the square sum of the difference between the moisture content of the detection points on the surface of the carbonized wood veneer layer and the average moisture content.

[0084] Specifically, the surface of the carbonized wood veneer layer is divided into a plurality of detection regions according to a square per unit length, and the center point of the detection region is the detection point of the moisture content.

[0085] Specifically, the moisture content is detected by a microwave moisture content detector; for example, a carbonized wood veneer layer with a length of 2000 mm and a width of 200 mm is evenly divided into 10 regions along the length direction, and each region has a size of 200 mm x 200 mm. The probe of the microwave moisture content detector is vertically aligned with the detection points to detect and record the moisture content of each detection point, respectively.

[0086] Specifically, the rotation and laying of the first grid-shaped substrate and the second grid-shaped substrate are laid by a mechanical arm.

[0087] In the implementation, the method of the present application adjusts the relative laying direction of the first and second grid substrates under different conditions when the wood blank has reached or is below the equilibrium moisture content of the use environment, the possibility of future hygroexpansion is greater than that of dry shrinkage, and the internal moisture content of the wood is very uniform, so the overall deformation trend is small. At this time, by laying the grid main direction of the first grid substrate parallel to the long edge direction of the composite floor blank and laying the grid main direction of the second grid substrate perpendicular to the long edge direction of the composite floor blank, the two layers of grids provide the strongest constraint in the longitudinal and transverse directions of the board, respectively, forming a kind of orthogonal grid reinforcing structure, uniformly resisting the possible slight stress from various directions, and improving the dimensional stability. When the wood blank is overall wet and will mainly undergo dry shrinkage in the future, but the shrinkage is uniform, mainly resisting the transverse shrinkage with the largest shrinkage rate along the grain direction of the wood, by laying the grid main direction of the first grid substrate parallel to the long edge direction and laying the grid main direction of the second grid substrate at an acute angle to the long edge direction to constrain the transverse shrinkage. When the wood blank has appropriate dryness as a whole, but the internal dryness is uneven, there are stress hotspots, and there is a risk of high warping due to future uneven expansion or complex internal shear stress. By laying the grid main direction of the first grid substrate and the grid main direction of the second grid substrate at an oblique angle to the long edge direction, and the included angle between the grid main direction of the first grid substrate and the grid main direction of the second grid substrate is an acute angle, the uneven stress is dispersed in multiple directions, thereby inhibiting the deformation caused by excessive local stress. When the wood blank is both wet and uneven, resulting in severe and uneven shrinkage in the future, and causing cracking and warping due to shrinkage stress and shear stress, by laying the grid main direction of the first grid substrate at an acute angle to the long edge direction and laying the grid main direction of the second grid substrate at an acute angle to the long edge direction, and the acute angle of the grid main direction of the first grid substrate to the long edge direction is less than the acute angle of the grid main direction of the second grid substrate to the long edge direction, a relatively balanced constraint force is provided in the longitudinal, transverse and diagonal directions to cope with complex and severe stress changes, and the stability of the performance of the composite floor is improved.

[0088] Specifically, the process of adjusting the cold pressing pressure of the cold pressing process according to the interlayer contact resistance of the first grid substrate includes:

[0089] Obtaining the interlayer contact resistance of the first grid substrate in the cold pressing process;

[0090] Comparing the interlayer contact resistance with the preset resistance;

[0091] If the interlayer contact resistance collected for a plurality of times is greater than or equal to the preset resistance, the cold pressing pressure is increased to the set value after the interlayer contact resistance decreases.

[0092] Specifically, under the condition that the grid aperture is 2-5 mm, the wire diameter is 0.3-0.6 mm, and the surface area of the composite floor blank is not more than 5 m 2 , the preset resistance generally has a value range of [10 mΩ, 50 mΩ], and the preferred embodiment of the preset resistance is 30 mΩ.

[0093] Those skilled in the art can understand that the optional range and the preferred embodiment of the preset resistance provided in the embodiment are the best values for the technical problem solved by the technical solution of the present application under the condition that the grid aperture is 2-5 mm, the wire diameter is 0.3-0.6 mm, and the surface area of the composite floor blank is not more than 5 m 2 . In actual application or experiment, those skilled in the art can adaptively adjust the preset resistance according to the actual application environment and application scenario.

[0094] Specifically, the starting condition for increasing the cold pressing pressure to the interlayer contact resistance after the cold pressing pressure is restored to the set value is that the interlayer contact resistance is greater than or equal to the preset resistance in five consecutive samplings.

[0095] In implementation, if the difference between the maximum interlayer contact resistance and the preset resistance exceeds 1 mΩ, the cold pressing pressure is 0.01 MPa, for example, the initial cold pressing pressure is 0.8 MPa, and the interlayer contact resistance is greater than or equal to 30 mΩ in five consecutive samplings, and the maximum interlayer contact resistance is 35 mΩ, then the pressure is increased to 0.8 MPa+0.01 MPa*5=0.85 MPa, and the pressure is restored to 0.8 MPa after the resistance value is reduced to 30 mΩ or less.

[0096] In implementation, the method of the present application increases the cold pressing pressure, and since the humidity distribution of the template is uneven, the hygroscopic performance of the template under the condition of environmental humidity is uneven. By increasing the cold pressing pressure during cold pressing, each layer is firmly bonded and fixed to resist the problem of poor internal stress uniformity caused by uneven hygroscopic performance, thereby preventing interlayer peeling.

[0097] Specifically, the process of determining the step-down value of the hot pressing pressure of the hot pressing mode according to the thickness change rate determination stage includes:

[0098] Obtaining the thickness change rate;

[0099] Comparing the thickness change rate with a preset change rate;

[0100] If the thickness change rate is greater than or equal to the preset change rate, the step-down value is reduced.

[0101] Specifically, the thickness change rate is a ratio of a difference between a thickness of the composite floor board blank at a starting time of the pre-heat pressing and a thickness of the composite floor board blank at an ending time of the pre-heat pressing to the thickness of the composite floor board blank at the starting time of the pre-heat pressing.

[0102] Specifically, the increase range of the cold-pressing pressure is determined according to a difference between the maximum interlayer contact resistance continuously collected and the preset resistance.

[0103] Specifically, the down-regulation step value is a product of the down-regulation multiple and the hot-pressing pressure at the last adjustment time minus the hot-pressing pressure at the last adjustment time.

[0104] Specifically, the phased down-regulation hot-pressing mode is to divide the total hot-pressing time into a plurality of equal hot-pressing stage durations, and the hot-pressing pressure in each hot-pressing stage duration is reduced by the down-regulation step value compared with the hot-pressing pressure in the adjacent last hot-pressing stage duration,

[0105] The number relationship between the hot-pressing stage duration and the adjustment time is that the number of the hot-pressing stage duration = the number of the adjustment time + 1.

[0106] Specifically, under the conditions that the grid aperture is 2-5 mm, the wire diameter is 0.3-0.6 mm, and the surface area of the composite floor board blank is not more than 5 m 2 The general value range of the preset change rate is [0.01, 0.03], and the preferred embodiment of the preset change rate is 0.015.

[0107] The skilled in the art can understand that the optional range and the preferred embodiment of the preset change rate provided in the embodiment are the best values selected for the effect of the technical problem solved by the technical scheme of the present application under the conditions that the grid aperture is 2-5 mm, the wire diameter is 0.3-0.6 mm, and the surface area of the composite floor board blank is not more than 5 m 2 In actual application or experiment, the skilled in the art can adaptively adjust the preset change rate according to the actual application environment and application scene.

[0108] In implementation, if the difference between the preset change rate and the thickness change rate exceeds 1% each time, the down-regulation multiple is increased to 1.05 times of the original down-regulation multiple to reduce the down-regulation compensation value, for example, the difference between the preset change rate and the thickness change rate is 2%, the current down-regulation multiple is 0.7, the initial hot-pressing pressure is 1.2 MPa, the total hot-pressing time is 6 minutes, the hot-pressing stage duration is 2 minutes, and the original down-regulation compensation value is 1.2 MPa-1.2 MPa x 0.7 = 0.36 MPa,

[0109] Then the down-regulation multiple increases to 0.7*1.05*1.05=0.77175≈0.77, and the down-regulation compensation value decreases to 1.2MPa-1.2MPa*0.77=0.276MPa.

[0110] In the implementation, the method obtains the thickness change rate of the composite floor blank by preheating pressing, and determines the hot-pressing pressure down-regulation step value of the stage down-regulation hot-pressing mode according to the change rate, so as to avoid uneven distribution of internal stress of the composite structure caused by excessive or insufficient hot-pressing pressure; the cold-pressing pressure determines the initial compactness of the blank, and in the hot-pressing activation stage, the grid-shaped substrate shrinks under the heat and does work, and the hot-pressing pressure restricts the shrinkage, so that the stress cannot be effectively released and even the structure is damaged and cannot be effectively guided to shrink in the direction, so that the structure is skewed, and by subsequently gradually reducing the pressure, a gradual environment is provided for the shrinkage of the grid-shaped substrate, the shrinkage force of the grid-shaped substrate is guided to act on the overall structure in a directional manner, and the stability of the mechanical properties of the composite board is improved.

[0111] In the implementation, the method hot-presses the composite floor blank in the stage down-regulation hot-pressing mode, so as to ensure that the composite floor can fully release internal stress during the forming process, improve the bonding strength between material layers, and thus enhance the dimensional stability and durability in the geothermal environment.

[0112] The application provides an example of a carbonized wood multi-insulation layer composite floor, which comprises:

[0113] The base fiberboard 1, the first grid-shaped substrate 2, the stress absorption layer plate 3, the second grid-shaped substrate 4 and the carbonized wood surface layer 5 are sequentially stacked and laid from bottom to top.

[0114] The thickness of the carbonized wood surface layer 5 is 2-4 mm.

[0115] The first grid-shaped substrate 2 and the second grid-shaped substrate 4 are respectively made of a mesh structure of nickel-chromium alloy, the mesh aperture is 2-5 mm, and the wire diameter is 0.3-0.6 mm.

[0116] The stress absorption layer plate 3 is a polyurethane elastomer layer with a thickness of 1-2 mm.

[0117] The base fiberboard 1 is a high-density fiberboard with a thickness of 8-12 mm.

[0118] In the implementation, the composite floor described in the present application is prepared by sequentially stacking the base fiberboard 1, the first grid-shaped substrate 2, the stress absorption layer plate 3, the second grid-shaped substrate 4 and the carbonized wood surface layer 5 from bottom to top, wherein the thickness of the carbonized wood surface layer 5 is controlled to be 2-4 mm, ensuring that it has good carbonization stability; the first grid-shaped substrate 2 and the second grid-shaped substrate 4 are made of nickel-chromium alloy, having good heat conduction performance and mechanical retraction characteristics; the stress absorption layer plate 3 is made of polyurethane elastomer, having good elasticity and stress buffering capacity, and can effectively absorb the local stress generated due to the expansion and contraction difference of the materials; the base fiberboard 1 is a high-density fiberboard, providing support and stability for the overall structure.

[0119] So far, the technical solutions of the present application have been described in combination with the preferred embodiments shown in the drawings, but those skilled in the art can easily understand that the protection scope of the present application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without deviating from the principles of the present application, and the technical solutions after these changes or replacements will all fall within the protection scope of the present application.

Claims

1. A method for manufacturing a carbonized wood multi-insulation layer composite floor, characterized by, The method comprises: carrying out carbonization treatment on wood blanks to obtain a carbonized wood surface layer, and detecting the average moisture content and moisture content distribution variance of the carbonized wood surface layer; embedding an alloy isolation layer into a mold to obtain a mesh-like base material; sequentially laying a base fiber plate, a first mesh-like base material, a stress absorption layer plate, a second mesh-like base material, and the carbonized wood surface layer in a bottom-up order, and cold pressing according to a cold pressing pressure to obtain a composite floor blank, wherein the cold pressing pressure of the cold pressing process is adjusted according to the interlayer contact resistance of the first mesh-like base material, and the relative laying directions of the first mesh-like base material and the second mesh-like base material are determined according to the average moisture content and the moisture content distribution variance; preheating and pressing the composite floor blank to obtain a thickness change rate of the composite floor blank; determining a step-down value of the hot pressing pressure of a stage-down hot pressing mode according to the thickness change rate; hot pressing the composite floor blank according to the stage-down hot pressing mode to obtain a finished product composite floor; wherein the moisture content distribution variance is the average of the sum of squares of the differences between the moisture contents of a plurality of detection points on the surface of the carbonized wood surface layer and the average moisture content.

2. The method for preparing carbonized wood multi-layer composite flooring according to claim 1, characterized in that, The process of determining the relative laying directions of the first mesh-like base material and the second mesh-like base material according to the average moisture content and the moisture content distribution variance comprises: respectively obtaining the average moisture content and the moisture content distribution variance; if the average moisture content is less than or equal to a preset moisture content and the moisture content distribution variance is less than or equal to a preset variance, laying the mesh main direction of the first mesh-like base material parallel to the long edge direction of the composite floor blank, and laying the mesh main direction of the second mesh-like base material perpendicular to the long edge direction of the composite floor blank; if the average moisture content is greater than the preset moisture content and the moisture content distribution variance is less than or equal to the preset variance, laying the mesh main direction of the first mesh-like base material parallel to the long edge direction, and laying the mesh main direction of the second mesh-like base material at an acute angle with the long edge direction; if the average moisture content is less than or equal to the preset moisture content and the moisture content distribution variance is greater than the preset variance, laying the mesh main direction of the first mesh-like base material and the mesh main direction of the second mesh-like base material at an oblique angle with the long edge direction, and the included angle between the mesh main direction of the first mesh-like base material and the mesh main direction of the second mesh-like base material is an acute angle; if the average moisture content is greater than the preset moisture content and the moisture content distribution variance is greater than the preset variance, laying the mesh main direction of the first mesh-like base material at an acute angle with the long edge direction, laying the mesh main direction of the second mesh-like base material at an acute angle with the long edge direction, and the acute angle between the mesh main direction of the first mesh-like base material and the long edge direction is smaller than the acute angle between the mesh main direction of the second mesh-like base material and the long edge direction.

3. The method for preparing carbonized wood multi-layer composite flooring according to claim 1, characterized in that, The surface of the carbonized wood surface layer is divided into a plurality of detection regions according to squares per unit length, and the center points of the detection regions are the detection points of the moisture content.

4. The method for preparing carbonized wood multi-layer composite flooring according to claim 3, characterized in that, The process of adjusting the cold pressing pressure of the cold pressing process according to the interlayer contact resistance of the first mesh-like base material comprises: acquiring an interlayer contact resistance of the first mesh substrate in the cold pressing process; comparing the interlayer contact resistance with a preset resistance; if the interlayer contact resistance is greater than or equal to the preset resistance for continuous times, increasing the cold pressing pressure to a preset value.

5. The method for preparing carbonized wood multi-layer composite flooring according to claim 4, characterized in that, The process of determining the step-down value of the hot pressing pressure of the stage-type hot pressing mode according to the thickness change rate comprises: acquiring the thickness change rate; comparing the thickness change rate with a preset change rate; if the thickness change rate is greater than or equal to the preset change rate, decreasing the step-down value.

6. The method for preparing carbonized wood multi-layer composite flooring according to claim 5, characterized in that, The thickness change rate is the ratio of the difference between the thickness of the composite floor blank at the start time of the pre-hot pressing and the thickness of the composite floor blank at the end time of the pre-hot pressing to the thickness of the composite floor blank at the start time of the pre-hot pressing.

7. The method for preparing carbonized wood multi-layer composite flooring according to claim 6, characterized in that, The increasing range of the cold pressing pressure is determined according to the difference between the maximum interlayer contact resistance continuously acquired and the preset resistance.

8. The method for preparing carbonized wood multi-layer composite flooring according to claim 7, characterized in that, The step-down value is the product of the hot pressing pressure at the last adjustment time and the step-down multiple.

9. A carbonized wood multi-insulation composite floor prepared by the method of any one of claims 1 to 8, characterized in that, The process comprises: laying the base fiberboard, the first mesh substrate, the stress absorption layer plate, the second mesh substrate and the carbonized wood surface layer in sequence from bottom to top; the thickness of the carbonized wood surface layer is 2-4 mm; the first mesh substrate and the second mesh substrate are both mesh structures made of nickel-chromium alloy, the mesh aperture is 2-5 mm, and the wire diameter is 0.3-0.6 mm; the stress absorption layer plate is a polyurethane elastomer layer with a thickness of 1-2 mm; the base fiberboard is a high-density fiberboard with a thickness of 8-12 mm.

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