CN100417625C - Kiln furniture for use in a non-oxidizing atmosphere - Google Patents
Kiln furniture for use in a non-oxidizing atmosphere Download PDFInfo
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- CN100417625C CN100417625C CNB2006101392354A CN200610139235A CN100417625C CN 100417625 C CN100417625 C CN 100417625C CN B2006101392354 A CNB2006101392354 A CN B2006101392354A CN 200610139235 A CN200610139235 A CN 200610139235A CN 100417625 C CN100417625 C CN 100417625C
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Abstract
Provided is a kiln furniture for use in a non-oxidizing atmosphere, which has SiC and Si3N4 and/or Si2N2O as main components, contains from 0.12 to 3.0 mass% of inorganic oxides other than an silicon oxynitride and silicon oxide. The kiln furniture for use in a non-oxidizing atmosphere according to the present invention causes neither significant deterioration in strength nor breakage even if it is used in a non-oxidizing atmosphere having an oxygen concentration of 1000 ppm or less and at the same time, has a greatly improved actual service life.
Description
Technical field
The present invention relates to the non-oxidizing atmosphere kiln furnitures.
Background technology
Silicon carbide (SiC) refractory materials is owing to have excellent thermotolerance and resistivity against fire, in occupation of consequence, for example is usually used in that ceramic ware burns till with column plate, other burn till usefulness anchor clamps, jacket kiln furnitures such as (sheath) industrial.This SiC refractory materials was by mixing the clay about 5～10 quality % in the SiC particle in the past, through mixing, moulding, burning till, made in conjunction with SiC with silicate minerals, for example clay mineral.But the SiC refractory materials that produces like this is because the crystal boundary joint portion is the low clay mineral of refractoriness, so easily in high temperature generation softening transform and oxidation.
Therefore, disclosed a kind of in the SiC particle, mix Si and moulding after, in non-oxidizing nitrogen containing atmosphere, burn till this formed body and make the technology of silicon nitride SiC refractory materials (silicon nitride combined with silicon carbide refractory material) (with reference to patent documentation 1).This SiC refractory materials is to use the bond material that is made of silicon nitride to combine the SiC particle, is intended to improve physical strength, resistance to sudden heating under the high temperature.But, even the SiC refractory materials that the method for being put down in writing according to patent documentation 1 produces also can not satisfy characteristics such as hot strength, resistance to sudden heating.
In order to solve the problems of the technologies described above, a kind of SiC of consisting of aggregate particle 60～90 quality %, Si have been disclosed
3N
4Matter and/or Si
2ON
2Crystal boundary joint portion 8～35 quality % of matter, the crystal boundary glassiness and/or crystal matter phase 1.0～15.0 quality % and metal Si are the technology (with reference to patent documentation 2) of the SiC refractory materials (silicon nitride combined with silicon carbide refractory material) of 0.05～2.0 quality %.This SiC refractory materials is improved hot strength and resistance to sudden heating by containing the metal Si of 0.05～5.0 quality %.
But, silicon nitride combined with silicon carbide refractory material in the past (with reference to patent documentation 1 and patent documentation 2), though can give play to its excellent characteristic when under atmospheric atmosphere, using, but when for example under oxygen concn is non-oxidizable atmosphere below the 1000ppm, using, compare with situation about under atmospheric atmosphere, using, intensity significantly reduces at short notice, and is final damaged, has very short problem actual service life.
Patent documentation 1: specially permit communique No. 2655699
Patent documentation 2: special fair 7-47507 communique
Summary of the invention
The present invention carries out in view of the problem that exists in the above-mentioned conventional art, its objective is provides a kind of non-oxidizing atmosphere kiln furnitures, even these kiln furnitures are under oxygen concn is non-oxidizable atmosphere below the 1000ppm, also significant deterioration in strength even breakage can be prevented, actual service life can be increased substantially simultaneously.
[1] non-oxidizing atmosphere kiln furnitures, main component are SiC and Si
3N
4And/or Si
2N
2O, and contain silicon oxynitride and silicon oxide inorganic oxide 0.12～3.0 quality % in addition.
[2] as the non-oxidizing atmosphere kiln furnitures of above-mentioned [1] record, aggregate portion uses SiC, and the aggregate joint portion is by the Si that contains 5～25 quality %
3N
4And/or Si
2N
2The refractory materials of O constitutes, and the inorganic oxide that exists in the described refractory materials is adjusted to Al
2O
3Account for 0.1～1.9 quality %, SiO
2Account for 0.5～6.7 quality %, remainder is made of SiC.
[3] as the non-oxidizing atmosphere kiln furnitures of above-mentioned [1] or [2] record, described inorganic oxide is present in the major part of described aggregate joint portion.
[4] as the non-oxidizing atmosphere kiln furnitures of each record in above-mentioned [1]～[3], the content of the elemental composition of described inorganic oxide is Al source 0.06～1 quality %, Fe source 0.3～0.5 quality %, Ca source 0.003～0.01 quality %, Ni source 0.004～0.01 quality %, Zr source 0.0008～0.01 quality %, O source 0.5～3 quality %.
[5] as the non-oxidizing atmosphere kiln furnitures of each record in above-mentioned [1]～[4], void content is 5～14%.
[6] as the non-oxidizing atmosphere kiln furnitures of each record in above-mentioned [1]～[5], the flexural strength decrement is no more than 15%.
Non-oxidizing atmosphere kiln furnitures of the present invention are even under oxygen concn is non-oxidizable atmosphere below the 1000ppm, also can prevents significant deterioration in strength even breakage, and can increase substantially actual service life.
Embodiment
Below, explain non-oxidizing atmosphere kiln furnitures of the present invention, but the present invention is not limited to these embodiments, without departing from the present invention, can carry out various changes, modification, improvement based on those skilled in the art's knowledge.
Non-oxidizing atmosphere kiln furnitures of the present invention, main component are SiC and Si
3N
4And/or Si
2N
2O, and contain silicon oxynitride and silicon oxide inorganic oxide 0.12～3.0 quality % in addition.Here, said among the present invention " non-oxidizing atmosphere " is meant and contains the atmosphere that oxygen concn is the such low concentration oxygen of 1～1000ppm.
Non-oxidizing atmosphere kiln furnitures of the present invention preferably contain the SiC as 69～89 quality % of aggregate, as the Si of 5～25 quality % of aggregate joint portion
3N
4And/or Si
2N
2O.Like this, refractory materials of the present invention has SiC as aggregate, and has the Si as parafacies in the aggregate joint portion
3N
4And/or Si
2N
2O.If less than above-mentioned scope, then be difficult to obtain sufficient resistance to sudden heating and intensity (flexural strength and Young's modulus) as the amount of the SiC of principal phase; If many, then because the parafacies of formation joint portion would be few, so can't give play to full intensity.
Here, non-oxidizing atmosphere of the present invention with the principal character of kiln furnitures is, the choosing of aggregate quality award from the ministry contains the SiC of 69～89 quality %, and the aggregate joint portion is by the Si that contains 5～25 quality %
3N
4And/or Si
2N
2The refractory materials of O constitutes, and in the inorganic oxide that exists in described refractory materials, is adjusted to Al
2O
3Be 0.1～1.9 quality %, SiO
2Be 0.5～6.7 quality %.In addition, kiln furnitures of the present invention, normally inorganic oxide is contained in (near 0%) in the aggregate portion hardly, preferably is present in the major part of aggregate joint portion.
The kiln furnitures that form by in the past silicon nitride combined with silicon carbide refractory material, normal conditions be as the aggregate clearance portion of the silicon carbide of aggregate (when aggregate during for particle in aggregate crystal boundary portion) in conjunction with silicon nitride, be present in simultaneously this aggregate clearance portion (when aggregate during for particle in aggregate crystal boundary portion) aggregate binding substances generation oxidation, the oxide compound of its oxidation generation forms overlay film, thereby can play the effect that suppresses combination between the aggregate, reaches refractory materials continuation oxidation.But, under non-oxidizing atmosphere, use in the past in the silicon nitride combined with silicon carbide refractory material, if forming the oxide compound of above-mentioned overlay film is reduced in turn, then can't on refractory materials, form stable overlay film, so the combination that the oxidation of refractory materials suppresses between effect and the aggregate just becomes difficult.Thereby the deterioration of refractory materials will become significantly, cause intensity significantly to descend at short notice, even damaged, and significantly shorten actual service life.
On the other hand, under the situation of the kiln furnitures that form by silicon nitride combined with silicon carbide refractory material that use in the present invention, by the Al in the inorganic oxide of doing one's utmost to suppress to be present in the aggregate joint portion as O elements fed source
2O
3And SiO
2Can improve bonding strength to greatest extent as the silicon nitride on the aggregate joint portion of the silicon carbide of aggregate, on refractory materials, form the stable oxide overlay film simultaneously, therefore can give the oxidation inhibition effect that refractory materials continues, even thereby under oxygen concn is non-oxidizable atmosphere below the 1000ppm, also significant deterioration in strength even breakage can be prevented, actual service life can be increased substantially simultaneously.
The refractory materials that uses among the present invention, the content of the elemental composition of preferred described inorganic oxide is Al source 0.06～1 quality %, Fe source 0.3～0.5 quality %, Ca source 0.003～0.01 quality %, Ni source 0.004～0.01 quality %, Zr source 0.0008～0.01 quality %, O source 0.5～3 quality % (content is meant shared ratio in whole refractory materialss).This be since when the content of each element for a long time, all in use be reduced separately and deterioration take place.On the other hand, when the content of each element after a little while, cause the strength degradation of bound fraction, perhaps the surface that contacts with atmosphere is difficult to generate firm glass ingredient, and deterioration takes place.
And, non-oxidizing atmosphere kiln furnitures of the present invention, preferred void content is 5～14%.This be because, if void content is big, then increase with the atmosphere gas contacted specific surface area, its result is reduced by atmosphere, and accelerated deterioration.On the other hand, if void content is little, though then degradation speed descends, resistance to sudden heating also can descend, and it is not preferred just being used as refractory materials.
And then, the refractory materials that uses among the present invention, preferred flexural strength decrement is no more than 15%.
Here, the definition of above-mentioned flexural strength decrement is, with the flexural strength of kiln furnitures after (under the non-oxidizing atmosphere) keeps 200 hours actual use under 1400 ℃, the inert atmosphere of oxygen concn 500ppm, the velocity of variation (%) of the flexural strength before using with reality.Above-mentioned flexural strength is to calculate according to the four-point bending test that JIS standard (JISR 1601) is stipulated.
Here, the refractory materials of Shi Yonging in the present invention, as the maximum particle diameter of the SiC of aggregate preferably below 2000 μ m, 50～300 μ m more preferably.This be because, when the maximum particle diameter of SiC during, apply the generation that thermal stresses can cause fine crack less than 50 μ m, if there is the above SiC particle of 50 μ m in the tissue, then this particle plays the effect that stops crackle to take place.With respect to this, if less than the SiC particle of 50 μ m, easily at crystal boundary generation crackle, and development rapidly, cause resistance to sudden heating to descend.On the other hand, if the maximum particle diameter of SiC aggregate surpasses 300 μ m, then be difficult to obtain sufficient resistance to sudden heating and intensity (flexural strength and Young's modulus).
The manufacture method of the refractory materials (silicon nitride combined with silicon carbide refractory material) that uses in the present invention then, is described.The refractory materials of Shi Yonging in the present invention is normally through raw material blending, mixing, cast molding, the demoulding, drying, burn till operation manufacturings such as (nitrogen atmosphere is burnt till), oxidation are burnt till, inspection.
Here, the manufacture method of the refractory materials of Shi Yonging in the present invention, molding procedure is preferably cast molding.Thus, the compactness of gained moulding product will be improved, so the intensity (flexural strength and Young's modulus) of the refractory materials after burning till can be improved according to the manufacture method of refractory materials of the present invention.
In addition, the manufacture method of the refractory materials of Shi Yonging is in fact preferably burnt till at 1350～1500 ℃ under nitrogen atmosphere in the present invention, and firing time is preferably 1～30 hour.Thus, in the manufacture method of refractory materials of the present invention, Si in the formed body and the nitrogen in the atmosphere react, and generate silicon oxynitride by silicon nitride and micro amount of oxygen on as the crystal boundary of the SiC particle of aggregate, make between the aggregate to mutually combine.
Here, non-oxidizing atmosphere of the present invention with kiln furnitures more preferably in fact by the SiO of 0.01～2 quality %
2The recrystallize SiC sintered compact that constitutes with the SiC of 99.99～98 quality %, in this case, even at oxygen concn is under the non-oxidizable atmosphere of (more preferably below the 500ppm) below the 1000ppm, can not cause the remarkable deterioration and the breakage of intensity yet, realize the long lifetime.
Embodiment
Below, illustrate in greater detail the present invention based on embodiment, but the present invention is not limited to these embodiment.
Embodiment 1 and embodiment 2, comparative example 1 and comparative example 2
In the main raw material that is mixed with silicon carbide 85 quality % and silicon 15 quality %, mixed aid (dispersion agent and tackiness agent) and water carry out raw material blending operation respectively.The raw material that obtains put in the trommel screen mix, the mud that will obtain with above-mentioned trommel screen mixing is injected in the gypsum mold, with the moisture absorption in the mud to gypsum mold, on mould, be controlled to specific thickness (6～8mm), obtain formed body separately.
The formed body that obtains is taken out from gypsum mold, and the intravital moisture of drying and moulding burns till the drying and moulding body that obtains 10 hours in 1400 ℃ in nitrogen atmosphere.Then, the sintered body that obtains in atmospheric atmosphere, was burnt till 10 hours in 1450 ℃ of oxidations.At last, check size and macroscopic irregularity after, obtain the kiln furnitures (embodiment 1 and embodiment 2, comparative example 1 and comparative example 2) that constitute by silicon nitride combined with silicon carbide refractory material separately as goods.
Embodiment 3～7, comparative example 3～9
In the main raw material that is combined with silicon carbide 85 quality % and silicon 15 quality %, compounding aid (tackiness agent) and water mix with muller.With the material extrusion molding that obtains is specific thickness (6～8mm).
After the intravital moisture of the moulding that obtains carried out drying, the drying and moulding body that obtains was burnt till 10 hours in 1400 ℃ in nitrogen atmosphere.Then, the sintered body that obtains in atmospheric atmosphere, was burnt till 10 hours in 1450 ℃ of oxidations.At last, check size and macroscopic irregularity after, obtain the kiln furnitures (embodiment 3～7, comparative example 3～9) that constitute by silicon nitride combined with silicon carbide refractory material separately as goods.
For the kiln furnitures that obtain separately (embodiment 1～7, comparative example 1～9), the content (quality %) of the inorganic oxide beyond table 1 expression silicon oxynitride and silicon oxide, the SiC of aggregate portion amount (quality %), the Si that contains as the aggregate joint portion
3N
4+ Si
2N
2O amount (quality %), be present in the Al in the inorganic oxide of aggregate joint portion
2O
3(quality %) and SiO
2(quality %).Here, the content of aggregate joint portion is ratio shared in whole goods.
Table 1
In addition, for the kiln furnitures that obtain separately (embodiment 1～7, comparative example 1～9), adopt the chemical constitution of the inorganic oxide in the wet chemistry assay determination aggregate joint portion.In its result of table 2 expression.Here, the Al source is Al in the inorganic oxide
2O
3, the Fe source is Fe
2O
3, the Ca source is CaCO
3, the Ni source is that NiO, Zr source are ZrO
2, the O source is each oxide raw material and/or burns till generation by oxidation.
And then, the flexural strength decrement of the void content of the kiln furnitures (embodiment 1～7, comparative example 1～9) that obtain separately in table 2 expression and the kiln furnitures separately that (oxygen concn 500ppm) is actual in non-oxidizing atmosphere when using.In addition, the flexural strength decrement of the kiln furnitures separately when table 3 expression changes oxygen concn in the oxygen atmosphere.
Table 2
Table 3. test back crooked damaged strength rating unit: %
Discuss
As shown in Table 1 and Table 2, in embodiment 1～7, because the Si that the aggregate joint portion is contained
3N
4And/or Si
2N
2O amount (quality %) is 5～25 quality %, and in the inorganic oxide that exists in the aggregate joint portion, is adjusted to Al
2O
3Be 0.1～1.9 quality %, SiO
2Be 0.5～6.7 quality %, the element component content of inorganic oxide satisfies Al source 0.06～1 quality % simultaneously, Fe source 0.3～0.5 quality %, Ca source 0.003～0.01 quality %, Ni source 0.004～0.01 quality %, Zr source 0.0008～0.01 quality %, the condition of O source 0.5～3 quality %, therefore compare with comparative example 1～9, the flexural strength decrement of the kiln furnitures separately when reality is used in non-oxidizing atmosphere is far away little, that is to say, even under oxygen concn is non-oxidizable atmosphere below the 1000ppm, also significant deterioration in strength even breakage can be prevented, actual service life can be increased substantially simultaneously.
In addition, as shown in table 3, even can know when the oxygen concn in the oxygen atmosphere changed to 1000ppm, 500ppm, 1ppm, have the kiln furnitures of the composition of embodiment 1～7, compare the remarkable deterioration that can prevent flexural strength more with comparative example 1～9.
Industrial applicability
Non-oxidizing atmosphere of the present invention can be applied to aptly with kiln furnitures The situation of burning till in the non-oxidizable atmosphere below the 1000ppm.
Claims (4)
1. the non-oxidizing atmosphere kiln furnitures is characterized in that, its main component is SiC and Si
3N
4And/or Si
2N
2O, and contain inorganic oxide 0.12～3.0 quality % beyond silicon oxynitride and the silicon oxide, the content of the elemental composition of described inorganic oxide is Al source 0.06～1 quality %, Fe source 0.3～0.5 quality %, Ca source 0.003～0.01 quality %, Ni source 0.004～0.01 quality %, Zr source 0.0008～0.01 quality %, O source 0.5～3 quality %; Described non-oxidizing atmosphere is no more than 15% with the flexural strength decrement of kiln furnitures.
2. as the non-oxidizing atmosphere kiln furnitures of claim 1 record, aggregate portion uses SiC, and the aggregate joint portion is by the Si that contains 5～25 quality %
3N
4And/or Si
2N
2The refractory materials of O constitutes, and the inorganic oxide that exists in the described refractory materials is adjusted to Al
2O
3Account for 0.1～1.9 quality %, SiO
2Account for 0.5～6.7 quality %, remainder is made of SiC.
3. as the non-oxidizing atmosphere kiln furnitures of claim 1 or 2 records, described inorganic oxide is present in the major part of described aggregate joint portion.
4. as the non-oxidizing atmosphere kiln furnitures of each record in the claim 1～3, void content is 5～14%.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005273476 | 2005-09-21 | ||
| JP2005273476 | 2005-09-21 | ||
| JP2006236628 | 2006-08-31 |
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|---|---|
| CN1935741A CN1935741A (en) | 2007-03-28 |
| CN100417625C true CN100417625C (en) | 2008-09-10 |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112500168B (en) * | 2021-01-25 | 2022-11-29 | 中钢集团洛阳耐火材料研究院有限公司 | Crystal boundary enhanced nitride combined silicon carbide kiln furniture |
Citations (6)
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|---|---|---|---|---|
| CN1045281C (en) * | 1993-09-03 | 1999-09-29 | 中国科学院上海硅酸盐研究所 | Silicon nitride combined with silicon carbide refractory material for pouring ladle gate |
| CN1061961C (en) * | 1997-07-16 | 2001-02-14 | 国家建筑材料工业局山东工业陶瓷研究设计院 | Nanometre silicon-carbide-silicon nitride complex phase ceramics and its preparation method |
| CN1528708A (en) * | 2003-10-16 | 2004-09-15 | 上海交通大学 | Ceramic material and process for making rotary spray head using same |
| CN1562883A (en) * | 2004-04-09 | 2005-01-12 | 清华大学 | Firebrick made from silicom nitride combined with silicon carbide in use for sidewall of electrobath for making aluminium |
| JP2005082451A (en) * | 2003-09-09 | 2005-03-31 | Ngk Insulators Ltd | SILICON NITRIDE-COMBINED SiC REFRACTORY AND ITS PRODUCING METHOD |
| CN1609057A (en) * | 2004-11-12 | 2005-04-27 | 清华大学 | Fast microwave sintering process of combined silicon nitride-silicon carbide refractorg material |
-
2006
- 2006-09-20 CN CNB2006101392354A patent/CN100417625C/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1045281C (en) * | 1993-09-03 | 1999-09-29 | 中国科学院上海硅酸盐研究所 | Silicon nitride combined with silicon carbide refractory material for pouring ladle gate |
| CN1061961C (en) * | 1997-07-16 | 2001-02-14 | 国家建筑材料工业局山东工业陶瓷研究设计院 | Nanometre silicon-carbide-silicon nitride complex phase ceramics and its preparation method |
| JP2005082451A (en) * | 2003-09-09 | 2005-03-31 | Ngk Insulators Ltd | SILICON NITRIDE-COMBINED SiC REFRACTORY AND ITS PRODUCING METHOD |
| CN1528708A (en) * | 2003-10-16 | 2004-09-15 | 上海交通大学 | Ceramic material and process for making rotary spray head using same |
| CN1562883A (en) * | 2004-04-09 | 2005-01-12 | 清华大学 | Firebrick made from silicom nitride combined with silicon carbide in use for sidewall of electrobath for making aluminium |
| CN1609057A (en) * | 2004-11-12 | 2005-04-27 | 清华大学 | Fast microwave sintering process of combined silicon nitride-silicon carbide refractorg material |
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