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CN103524140B - Oxide ceramic fiber board - Google Patents

Oxide ceramic fiber board Download PDF

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Publication number
CN103524140B
CN103524140B CN201310437109.7A CN201310437109A CN103524140B CN 103524140 B CN103524140 B CN 103524140B CN 201310437109 A CN201310437109 A CN 201310437109A CN 103524140 B CN103524140 B CN 103524140B
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China
Prior art keywords
ceramic fiber
fiber board
oxide ceramic
silicon sol
fibre
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Expired - Fee Related
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CN201310437109.7A
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CN103524140A (en
Inventor
刘家臣
申偲伯
董学
刘珊
王明超
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Tianjin University
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Tianjin University
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Abstract

The invention discloses an oxide ceramic fiber board. The oxide ceramic fiber board comprises raw material components including silica sol, chopped fibers and a surfactant in a mass ratio of 1000:(100-200):(1-10), wherein the silica sol is prepared by mixing tetraethyl orthosilicate, ethanol and water in a mass ratio of (2-10):(1-9):(1-9), performing vacuum filtration to mold a wet blank, and after the gel is dried, and calcining the gel at 1200-1400 DEG C for 0.5-4 hours. According to the invention, the volume density (0.3g/cm<3>-0.7g/cm<3>) of the ceramic fiber board can be adjusted by changing the concentration (5-20wt%) of the silica sol, and the normal temperature heat conductivity of the oxide ceramic fiber board is 0.07-0.2W/m.K and is adjustable. The oxide ceramic fiber board disclosed by the invention is simple in process and environment-friendly, and can be prepared into any size and shape, and the long-term use temperature of the oxide ceramic fiber board can reach 1600 DEG C.

Description

Oxide ceramic fiber board
Technical field
The present invention relates to a kind of rigid hot structured material, particularly relate to a kind of Oxide ceramic fiber board and preparation method thereof.
Background technology
Oxide ceramic fiber board, as a kind of novel rigid hot structured material, is widely used in tunnel furnace, retort furnace as furnace lining; Ladle, coke-oven plant's pipeline are as thermofin etc.Ceramic beaverboard is one of deep processed product of ceramic fiber, has following advantage: high porosity, high physical strength, high temperature tolerance, lower thermal conductivity, have certain toughness simultaneously compared to cloth, tapetum fibrosum, fibrefelt etc.
Selecting a kind of suitable high-temperature fibre and high-temperature agglomerant to be the prerequisites preparing ceramic beaverboard is also core element.Chemically composition and weave construction on oxide ceramic fibre can be divided into: Zirconium oxide fibre, sapphire whisker (80,95), mullite fiber (72), aluminum silicate fiber, silica fiber, high silica fiber.From Fibre diameter and length-to-diameter ratio, oxide fibre can be divided into: macrofiber (length: tens centimetres to hundreds of rice), staple fibre (length: hundreds of micron to tens centimetre), whisker (length: below hundreds of micron).
The difference of ceramic fiber the Nomenclature Composition and Structure of Complexes directly determines the high/low temperature intensity, creep resistance, Young's modulus etc. of fiber; The length of fiber determines the final form of fibre product: some fibre spinnable cloth, can blanket processed, can papermaking, some fiber is just not all right, the Application Areas that the different fibre product of final decision is proprietary separately.
High-temperature agglomerant is divided into (1) reaction bonded type binding agent from bonding mechanism: norbide, silicon carbide, and during high temperature, sintering aid autoxidation is that high-viscosity melt or nanometer high activity oxide bond anchoring fiber node.(2) high-temperature stream ejector half binding agent: highly reactive form of oxygen SiClx, boron oxide, aluminum oxide.Be divided into (1) solid-state adhesion agent and (2) colloidal binder from states of matter: silicon sol, Alumina gel, zirconium colloidal sol, water glass etc., application solgel reaction anchoring fiber node, obtain high strength base substrate, high temperature sintering obtains goods.
How to select the characteristic such as ultimate compression strength, compression resilience, void content, thermal conductivity of high-temperature agglomerant meeting remarkably influenced fibrous matrix.When adopting solid-state adhesion agent, add-on is not easily evenly distributed at least in fibrous matrix, stress concentration and affect the mechanical property of fibre product; Add-on at most fibre product volume density is large, and then thermal conductivity increases (fibre product normal temperature thermal conductivity and volume density linear), and void content reduces.In a lot of situation, colloidal state and solid-state high-temperature agglomerant can be with the use of.
The basal component of silicon sol is hydration SiO 2(amorphous Si O 2), SiO 2be dispersed in water or in ethanol with micelle form, outward appearance is creamy white or clear, has hydrophilic increasing oiliness, and available distilled water diluting is to any concentration, and dilution rear stability strengthens.There is polymolecularity, preferably wear resistance, good light transmission.The Nature comparison of silicon sol is complicated, SiO 2concentration, size of particles, specific surface area, the dispersity of system, temperature, minor component in amount of cure and system the factor such as character all can affect the performance of silicon sol.
Alkaline silica sol is by being raw material with water glass, is obtained by ion exchange method, and after cation and anion exchange, obtain the polysilicon acid solution of less stable, solution is slightly acidic, makees stablizer with NaOH or other reagent, by the stable range of pH modulation 8.5 ~ 9.5.SiO 2content 15% ~ 40%, Na 2o content 0.1% ~ 0.5%, owing to containing a certain amount of Na in alkaline silica sol 2o, refractoriness is lower than acidic silicasol.
Filler: 1, filler can be hollow glass ball, hollow ball is in fibrous matrix network gap, and one is increase matrix strength, and two is reduce heat conduction.2, filler also can be Silica hydrogel: first prepare fibre network matrix, and after vacuum impregnation silicon sol, make Silica hydrogel be filled in fibre network gap through supercritical drying, this structure largely can reduce the thermal conductivity of goods.
Sintering: main consideration two factors: sintering temperature must lower than the impaired temperature of the intensity of fiber, produce the temperature of cohesive strength higher than high-temperature agglomerant simultaneously, say from this point, a kind of ceramic fiber of rational Match and high-temperature agglomerant are the core places that success prepares ceramic beaverboard!
Generally speaking, the forming method of ceramic beaverboard is all colloidal formation: as gel injection, can to realize complicated shape shaping, but monomer is poisonous, and slurry and gelation process control more complicated; Vacuum filtration is shaping relatively simple, has more general applicability, is more suitable for heavy industrialization application.
Summary of the invention
The present invention is directed to the deficiency of existing Oxide ceramic fiber board technology of preparing, provide a kind of method of " it is shaping that acidic silicasol high-temperature agglomerant adds vacuum filtration " that adopts to prepare Oxide ceramic fiber board; The long-time use temperature of ceramic beaverboard prepared by the method reaches 1600 DEG C (using Zirconium oxide fibre as matrix), and the volume density of ceramic beaverboard can regulate arbitrarily within the specific limits according to the concentration of silicon sol.
The present invention realizes above-mentioned purpose by following technical solution, and concrete steps are as follows:
A kind of Oxide ceramic fiber board, its raw material consists of silicon sol, chopped strand and tensio-active agent, and its mass ratio is 1000:100 ~ 200:1 ~ 10;
This Oxide ceramic fiber board preparation method, has the following step:
(1) silicon sol is prepared
Tetraethoxy, second alcohol and water are mixed according to the mass ratio of 2 ~ 10:1 ~ 9:1 ~ 9, with inorganic or organic acid, pH is transferred to 1 ~ 3, magnetic agitation 2 hours, obtain silicon sol and high-temperature agglomerant that concentration is 5wt% ~ 20wt%;
(2) fibre stuff is prepared and vacuum filtration is shaping
Select one or more mixtures in aluminum silicate fiber, mullite fiber, sapphire whisker, Zirconium oxide fibre, silica fiber, high silica fiber, smash with hollander, obtain the chopped strand that length-to-diameter ratio is 50 ~ 500; Joined in silicon sol by the tensio-active agent of chopped strand and step (1) and prepare fibre stuff, its composition and ratio is: silicon sol: chopped strand: the mass ratio of tensio-active agent is 1000:100 ~ 200:1 ~ 10; Again fibre stuff quick oscillation is stirred 30 minutes, then fibre stuff is injected mould, vacuum filtration is shaping, obtains wet base after gel;
(3) dry and calcining
By the wet base of step (2) after dry 48 hours, microwave heating, in 1200 DEG C ~ 1400 DEG C calcinings 0.5 ~ 4 hour, obtained Oxide ceramic fiber board.
Inorganic or the organic acid of described step (1) is the one in sulfuric acid, hydrochloric acid, nitric acid or acetic acid.
The tensio-active agent of described step (2) is the one in sodium alkyl benzene sulfonate, sodium alkyl sulfate, sodium soap or alkyl sodium sulfonate, and its concentration is 0.2 ~ 0.5wt%.
The shape of cross section of the forming mould of described step (2) is arbitrary shape, and mold bottom has some through holes for draining.
The high-temperature calcination of described step (3) can be Resistant heating, globars heating or Si-Mo rod heating.
Tool of the present invention has the following advantages and positively effect:
(1) use temperature of Oxide ceramic fiber board of the present invention can change (1000 DEG C ~ 1600 DEG C) according to ceramic fiber difference; By changing the concentration of high-temperature agglomerant, the volume density (0.3g/cm of ceramic beaverboard can be regulated 3~ 0.7g/cm 3); Meanwhile, the normal temperature thermal conductivity of Oxide ceramic fiber board is that 0.07W/mK ~ 0.2W/mK is adjustable.
(2) the present invention adopts microwave heating significantly can shorten ceramic beaverboard required time in calcination process, energy-saving and emission-reduction.
(3) the present invention adopts acidic silicasol as high-temperature agglomerant, and the component of acidic silicasol is 100% pure SiO 2, do not use any organic binder bond, improve the use temperature of fiberboard.
Accompanying drawing explanation
Scanning electronic microscope (SEM) picture of Fig. 1 embodiment of the present invention 1 mullite fiber plate.
Embodiment
Be the present invention is further explained and illustrates below in conjunction with embodiment, but the present invention is not constituted any limitation.The raw material used in following examples is commercially available analytical pure raw material.
Embodiment 1
By tetraethoxy, second alcohol and water in mass ratio 10:9:9 mix, with nitric acid adjust pH to 1, magnetic agitation 2 hours, obtains silicon sol high-temperature agglomerant.The chopping of mullite loose wool is obtained the chopped strand that length-to-diameter ratio is 300,100g fiber is joined in 1000mL silicon sol, then the Sodium dodecylbenzene sulfonate solution that 10mL concentration is 0.2wt% is added successively, stir after 30 minutes, again fibre stuff is injected mould, vacuum filtration is shaping, obtains wet base after gel.Base will be wet in atmosphere dry 24 as a child, at 1300 DEG C of calcinings, 2 hours obtained Oxide ceramic fiber board goods.Product volume density is 0.3g/cm 3~ 0.4g/cm 3, normal temperature thermal conductivity is 0.07W/mK ~ 0.1W/mK, and its long-time use temperature is 1400 DEG C.As shown in Figure 1, mullite fiber overlaps mutually the microscopic appearance of goods, interspersed formation network matrix, and high-temperature agglomerant adheres to fiber nodes, there is the hole that a lot of three-dimensional runs through around fiber.
Embodiment 2
By tetraethoxy, second alcohol and water in mass ratio 2:1:1 mix, with hydrochloric acid adjust pH to 2, magnetic agitation 2 hours, obtains silicon sol high-temperature agglomerant.The chopping of aluminum oxide loose wool is obtained the chopped strand that length-to-diameter ratio is 200,150g fiber is joined in 1000mL silicon sol, then the Sodium dodecylbenzene sulfonate solution that 10mL concentration is 0.3wt% is added successively, stir after 30 minutes, again fibre stuff is injected mould, vacuum filtration is shaping, obtains wet base after gel.Base will be wet in atmosphere dry 24 as a child, at 1350 DEG C of calcinings, 3 hours obtained Oxide ceramic fiber board goods.Product volume density is 0.4g/cm 3~ 0.5g/cm 3, normal temperature thermal conductivity is 0.1W/mK ~ 0.14W/mK, and its long-time use temperature is 1500 DEG C.
Embodiment 3
By tetraethoxy, second alcohol and water in mass ratio 4:1:1 mix, with sulfuric acid adjust pH to 1, magnetic agitation 2 hours, obtains silicon sol high-temperature agglomerant.The chopping of zirconium white loose wool is obtained the chopped strand that length-to-diameter ratio is 100,100g fiber is joined in 1000mL silicon sol, then the Sodium dodecylbenzene sulfonate solution that 10mL concentration is 0.4wt% is added successively, stir after 30 minutes, again fibre stuff is injected mould, vacuum filtration is shaping, obtains wet base after gel.Base will be wet in atmosphere dry 24 as a child, with microwave Muffle furnace at 1400 DEG C of calcinings, 1 hour obtained Oxide ceramic fiber board goods.Product volume density is 0.6g/cm 3~ 0.7g/cm 3, normal temperature thermal conductivity is 0.17W/mK ~ 0.2W/mK, and its long-time use temperature is 1600 DEG C.
Various raw material cited by the present invention and the span of various processing parameter can realize the present invention, then this is illustrated no longer one by one.

Claims (4)

1. an Oxide ceramic fiber board, its raw material consists of silicon sol, chopped strand and tensio-active agent, and its mass ratio is 1000:100 ~ 200:1 ~ 10;
This Oxide ceramic fiber board preparation method, has the following step:
(1) silicon sol is prepared
Tetraethoxy, second alcohol and water are mixed according to the mass ratio of 2 ~ 10:1 ~ 9:1 ~ 9, with inorganic or organic acid, pH is transferred to 1 ~ 3, magnetic agitation 2 hours, obtain silicon sol and high-temperature agglomerant that concentration is 5wt% ~ 20wt%;
(2) fibre stuff is prepared and vacuum filtration is shaping
Select one or more mixtures in aluminum silicate fiber, mullite fiber, sapphire whisker, Zirconium oxide fibre, silica fiber, high silica fiber, smash with hollander, obtain the chopped strand that length-to-diameter ratio is 50 ~ 500; Chopped strand and tensio-active agent are joined in silicon sol and prepare fibre stuff, its composition and ratio is: silicon sol: chopped strand: the mass ratio of tensio-active agent is 1000:100 ~ 200:1 ~ 10; Again fibre stuff quick oscillation is stirred 30 minutes, then fibre stuff is injected mould, vacuum filtration is shaping, obtains wet base after gel;
(3) dry and calcining
By the wet base of step (2) after dry 48 hours, microwave heating, in 1200 DEG C ~ 1400 DEG C calcinings 0.5 ~ 4 hour, obtained Oxide ceramic fiber board.
2. Oxide ceramic fiber board according to claim 1, is characterized in that, the inorganic or organic acid of described step (1) is the one in sulfuric acid, hydrochloric acid, nitric acid or acetic acid.
3. Oxide ceramic fiber board according to claim 1, is characterized in that, the tensio-active agent of described step (2) is the one in sodium alkyl benzene sulfonate, sodium alkyl sulfate, sodium soap or alkyl sodium sulfonate, and its concentration is 0.2 ~ 0.5wt%.
4. Oxide ceramic fiber board according to claim 1, is characterized in that, the shape of cross section of the mould of described step (2) is arbitrary shape, and mold bottom has some through holes for draining.
CN201310437109.7A 2013-09-23 2013-09-23 Oxide ceramic fiber board Expired - Fee Related CN103524140B (en)

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