WO2007055776A2 - REACTION INVERSE DE FRITTAGE DE COMPOSITES Si3N4/SiC - Google Patents

REACTION INVERSE DE FRITTAGE DE COMPOSITES Si3N4/SiC Download PDF

Info

Publication number
WO2007055776A2
WO2007055776A2 PCT/US2006/033405 US2006033405W WO2007055776A2 WO 2007055776 A2 WO2007055776 A2 WO 2007055776A2 US 2006033405 W US2006033405 W US 2006033405W WO 2007055776 A2 WO2007055776 A2 WO 2007055776A2
Authority
WO
WIPO (PCT)
Prior art keywords
silicon
grains
sic
sio
silicon nitride
Prior art date
Application number
PCT/US2006/033405
Other languages
English (en)
Other versions
WO2007055776A3 (fr
Inventor
Jia-Lin Sun
Original Assignee
The Vanguard Company, Llc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US11/279,461 external-priority patent/US7446066B1/en
Application filed by The Vanguard Company, Llc filed Critical The Vanguard Company, Llc
Priority to EP06802409A priority Critical patent/EP1951486A4/fr
Publication of WO2007055776A2 publication Critical patent/WO2007055776A2/fr
Publication of WO2007055776A3 publication Critical patent/WO2007055776A3/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/628—Coating the powders or the macroscopic reinforcing agents
    • C04B35/62802—Powder coating materials
    • C04B35/62805—Oxide ceramics
    • C04B35/62807—Silica or silicates
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/14—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silica
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/56—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides
    • C04B35/565—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides based on silicon carbide
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/62605—Treating the starting powders individually or as mixtures
    • C04B35/62645—Thermal treatment of powders or mixtures thereof other than sintering
    • C04B35/62655—Drying, e.g. freeze-drying, spray-drying, microwave or supercritical drying
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3418—Silicon oxide, silicic acids, or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/38—Non-oxide ceramic constituents or additives
    • C04B2235/3817—Carbides
    • C04B2235/3826—Silicon carbides
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/38—Non-oxide ceramic constituents or additives
    • C04B2235/3852—Nitrides, e.g. oxynitrides, carbonitrides, oxycarbonitrides, lithium nitride, magnesium nitride
    • C04B2235/3873—Silicon nitrides, e.g. silicon carbonitride, silicon oxynitride
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/38—Non-oxide ceramic constituents or additives
    • C04B2235/3895—Non-oxides with a defined oxygen content, e.g. SiOC, TiON
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/42—Non metallic elements added as constituents or additives, e.g. sulfur, phosphor, selenium or tellurium
    • C04B2235/428—Silicon
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5427—Particle size related information expressed by the size of the particles or aggregates thereof millimeter or submillimeter sized, i.e. larger than 0,1 mm
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5436—Particle size related information expressed by the size of the particles or aggregates thereof micrometer sized, i.e. from 1 to 100 micron
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5463—Particle size distributions
    • C04B2235/5481—Monomodal
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
    • C04B2235/604—Pressing at temperatures other than sintering temperatures
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
    • C04B2235/6562—Heating rate
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
    • C04B2235/6567—Treatment time
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/658—Atmosphere during thermal treatment
    • C04B2235/6583—Oxygen containing atmosphere, e.g. with changing oxygen pressures
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/66—Specific sintering techniques, e.g. centrifugal sintering
    • C04B2235/661—Multi-step sintering
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/74—Physical characteristics
    • C04B2235/76—Crystal structural characteristics, e.g. symmetry
    • C04B2235/767—Hexagonal symmetry, e.g. beta-Si3N4, beta-Sialon, alpha-SiC or hexa-ferrites
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/80—Phases present in the sintered or melt-cast ceramic products other than the main phase

Definitions

  • Si 3 N 4 will be oxidized before SiC within the sintering temperature range.
  • Si 3 N 4 reacts with oxygen as expressed in reactions 2.30, 2.26 and 2.16 , which may proceed depending on the oxygen partial pressure.
  • FIG. 3 it can be seen that when p Oi is relatively low, Si 2 N 2 O is first produced, and the reaction product is SiO 2 with rising p Oi .
  • SiO because it is a gaseous compound, the discussion may be carried out through the relationship of SiO and SiO 2 .
  • a ⁇ G A r G ⁇ + RTIn(p M //) - ⁇ PN J P ⁇ T 2.49
  • Si 2 N 2 O is produced, the gas pressure of SiO and N 2 produced can break through the surface film at a relatively low temperature. But the Si 2 N 2 O can still form the protecting film. If the oxygen partial pressure is high enough to oxidize Si 2 N 2 O, then the protecting SiO 2 film is formed. This is also the basis of forming a Si 2 N 2 O/ Si 3 N 4 /SiC system.
  • the sintering process of reverse reaction sintering Si 3 N 4 /SiC composites is actually the reaction process of controlling oxidation, by reacting to produce new and active SiO 2 and a little
  • Si 2 N 2 O which segregates onto the SiC and Si 3 N 4 particle surfaces, thus aiding in sintering.
  • oxygen must first diffuse through the SiO 2 film to reach the reaction interface; the oxidation reaction is thus limited by the diffusion of oxygen through the silica shells that form on the respective particles.
  • the gaseous reaction products such as CO 2 , CO, SiO, N 2 and NO, and the like, are emitted by reverse diffusion from the interface through the silica layer, which also influences the diffusion of oxygen therethrough to the interface.
  • the driving force of sintering is the surface energy (surface tension).
  • the powder material is typically highly dispersed, and more typically is characterized by an extremely large specific surface area, and thus has relatively high surface energy.
  • the reduction of surface free energy is the main driving force of sintering the material.
  • the difference between the surface energy ( ⁇ t ,) of powder particles and the interface energy ( ⁇ s ) of crystal particles of multi-crystal sinter will result in the reduction of free energy of system, and the ratio S b / ⁇ s is is thus a measure of the sintering character of powder.
  • the first step of sintering process can be regarded as the compacting of the body formed of partially compacted particulate material, such as a mixture of SiC and S 3 N 4 particles.
  • the body is heated in the air and a thin silica layer is formed around substantially all of the particles; the silica layer thus prevents further oxidation of the silicaeous particles.
  • impurities in the raw material may be reacted with SiO 2 to produce a lower melting point eutectic material.
  • the viscosity of eutectic liquid is relatively low and the particles making up the body may be redistributed by surface tension.
  • the second step of sintering process is typically one of dissolving-diffusing-reseparating out.
  • the diffusion of O 2 through the silica layer limits the reaction rates. Due to the existence of the eutectic liquid, the speed of compacting the body is increased. After the particles are redistributed, they are separated by the thin liquid film. As the body densities, the liquid separating the particles becomes quite thin. Typically, the thinner the liquid film, the greater the pressure of the particles. The solubility at the point of particles contacting is increased due to this pressure. The material at the contact points is gradually dissolved into the liquid, and then transferred to other surface and separated out.
  • the third step of sintering process is the process of grain growth. Due to the shrinkage/disappearance/closure of the pores, sintering speed is reduced but the microstructure of the material still continues to change. That is, other phenomena such as the grain growth, necking, and capillary action of liquid filing pores still continue to occur, but at slower rates. During the cooling process, the remaining interfacial liquid is hardened to glassy state or partially crystallized. If an exterior force is applied, the degree of compacting between the particles may be accelerated. As the thermodynamic equations illustrate, the sintering process is accompanied by the oxidation of Si 3 N 4 , which provides a continuous emission of N 2 . The microstructure analysis of reverse reaction sintering Si 3 N 4 ZSiC composites
  • the study on microstructure of reverse reaction sintering Si 3 N 4 ZSiC composites includes the study on the structure of micro minerals and of micro pores.
  • the surface area and inner area of sample Pl, P2, P3 and P4 were analyzed by XRD, SEM and EPMA in order to confirm the microstructure of the sintered samples.
  • the result of the analyses are as follows: The study on microstructure of SiC-SijST ⁇ sintering system
  • FIGs. 6 and 7 are surface area (0-5mm) and inner area (8- 16mm) XRD patterns, respectively.
  • the samples were prepared by mixing the constituent powders and forming them into green bodies. This was done by pressing at about 105 MPa; some samples required small amounts of binder (dextrine solution) to allow pressing.
  • the green bodies were dried at 105 degrees Celsius for 10 hours.
  • the green bodies were then heated at a rate of 50 degrees CelsiusZhour to about 800 degrees Celsius, where they were allowed to soak for 8 to 10 hours.
  • the samples were then heated at a rate of 50 degrees CelsiusZhour to about 1450 degrees Celsius, where they were allowed to soak for 5 hours.
  • the samples were then cooled to room temperature. All sintering was done in air under normal atmospheric pressures.
  • FIG. 6 shows that the surface sample of Pl is one of 0-5mm area and its main crystal phases are SiC, Si 3 N 4 and SiO 2 .
  • FIG. 7 shows that the interior of sample of Pl is mainly composed of SiC, Si 3 N 4 and SiO 2 , but with more Si 3 N 4 and less SiO 2 than at the surface.
  • FIGs. 8 and 9 relate to a nitrogen-containing oxide found in the section of sample Pl and its morphology.
  • SEM and ESA show the existence of nitride in the state of conglomerate, indicating that Si 2 N 2 O is produced during the oxidation of Si 3 N 4 .
  • the absence of the primary peak for Si 2 N 2 O in XRD pattern indicates that either the amount of Si 2 N 2 O present is relatively small, the Si 2 N 2 O is amorphous or glassy, or the Si 2 N 2 O crystal structure includes sufficient impurities so as to be substantially distorted.
  • Sample P2 was analyzed by XRD and EPMA; the results are presented as FIGs. 10 and 11, and are of the surface (0-5mm) and interior area (8- 16mm), respectively.
  • metallic silicon is present in the sintered matrix of P2.
  • the oxidation products of sintering are Si 2 N 2 O and a little SiO 2 ; the main crystal phases are hexagonal SiC and Si 3 N 4 .
  • the content of crystal phase Of Si 2 N 2 O and SiO 2 in the surface area (FIG.10) of the sample are relatively high (compared with the peak strength).
  • Metallic silicon still exists in the surface area (FIG. 10).
  • There is relatively little Si 2 N 2 O crystal phase present in the inner area (FIG. 11) is little.
  • Electron microprobe analysis results for sample P2 are shown in FIGs. 12 and 13.
  • the surface area of P2 the distribution of metallic silicon, with the diameter of the silicon particles being less than about 50 ⁇ m; the metallic silicon particles are distributed in the among of coarse SiC particles, which indicates that metallic silicon in the surface area has not been disappeared totally after being sintered at the relatively high temperature of 1450 degrees Celsius.
  • there is obvious chromatic aberration in the surface area along the pores extending below the surface see FIG. 13).
  • Comparison of the distribution of O, C and N indicates that the surface of the particles have an area of high oxygen content. Thus, the reaction of oxygen diffusing toward surrounding area occurs around the pores.
  • FIG. 14 illustrates the interior area (8-16mm) morphology of sample P2, and shows that the content of metallic silicon in the inner area is relatively greater and concentrated in the voids of SiC. Such distribution appears to be beneficial to the oxidation resistance of SiC and thus improves the binding strength. Apparently, metallic silicon is melted into the SiC voids and acts as a binder.
  • FIG 15 illustrates the Si 2 N 2 O mineral morphology in inner area (8-18mm) of sample P2.
  • Significant Si 2 N 2 O is present in the interior area of sample P2.
  • Si 2 N 2 O is present on the surface of grains Si 3 N 4 as short, cylinder crystals. Further, silica has precipitated in the surrounding area. Inner oxidation of pores is also be observed, and the oxidation process extends toward the sample interior along the void surface area. SiO produced by oxidation is precipitated onto the surface due to total oxidation of exterior surface, which prevents further oxidation.
  • the Si 2 N 2 O crystal morphology is not as obvious, and the Si 2 N 2 O crystals seem to grow finer. So the ratio of remnant nitrogen is high and the strength of the sintered P2 sample was high as well.
  • the X-ray pattern confirms the presence of Si 2 N 2 O. And it is probable that the oxygen diffused into the matrix reacts preferentially with metallic silicon.
  • the metal silicon (surface and inner area) in the sample matrix is not totally oxidation during the sintering of the SiC-Si 3 N 4 sample.
  • the metallic silicon apparently infiltrates into the void of the SiC crystals at the sintering temperature and acts in a binding role, likely as a plastic phase. Meanwhile, metallic silicon reacts more easily with oxygen than does Si 3 N 4 , so the formation of a Si 2 N 2 O phase is not observed, and thus more Si 3 N 4 is present after the sample is sintered.
  • the sample thus produced has better chemical durability characteristics, which were confirmed by the erosion test of cryolite-sodium fluoride melt test.
  • the SiO 2 phase in the surface area is -M 8 relatively high (comparison of peak strength) compared to that of the inner area (significant amounts of SiO 2 were not observed in X-ray pattern).
  • the primary peak of Si 2 N 2 O mineral was detected both on surface and interior of the P3 sample, indicating that the Si 2 N 2 O content was higher and SiO 2 may be present in an amorphous or glassy state; if so, the structure is suited for use in a thermal shock resistance environment.
  • FIG.18 is surface EPMA pattern of sample P3;
  • FIG. 19 is surface area Si 2 N 2 O morphology of sample P3;
  • FIG. 20 is interior area (8-16m) morphology of sample P3.
  • the analysis of FIG. 18 shows that the oxidation product OfSi 3 N 4 on the surface is Si 2 N 2 O and SiO 2 , and the crystal grows very well (seeing FIG. 19). Meanwhile, Si 3 N 4 here may be covered by SiO 2 and Si 2 N 2 O and thus cannot be detected.
  • FIG. 20 shows that Si 2 N 2 O crystasl from the oxidation of Si 3 N 4 are very fine; this may be an effect of the speed of gas diffusion through the silica layer.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Ceramic Products (AREA)

Abstract

La présente invention concerne un procédé de fabrication d'un corps fritté composite de nitrure de silicium/carbure de silicium, comprenant le mélange d’une quantité prédéterminée de poudre de nitrure de silicium avec une quantité prédéterminée de poudre de carbure de silicium, le traitement thermique de la poudre mélangée résultante à une température située entre environ 800 et 1500 °C sous une atmosphère de frittage constituée essentiellement d’azote, et la production d'un film mince de silice autour des grains individuels de nitrure de silicium et de carbure de silicium. Le film mince de silice est utile pour retarder la diffusion de l’oxygène dans les particules de nitrure de silicium et ralentir leur oxydation. La pression de l'atmosphère de frittage n'est pas sensiblement supérieure à la pression atmosphérique.
PCT/US2006/033405 2005-11-07 2006-08-28 REACTION INVERSE DE FRITTAGE DE COMPOSITES Si3N4/SiC WO2007055776A2 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP06802409A EP1951486A4 (fr) 2005-11-07 2006-08-28 REACTION INVERSE DE FRITTAGE DE COMPOSITES Si3N4/SiC

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US59704905P 2005-11-07 2005-11-07
US60/597,049 2005-11-07
US11/279,461 US7446066B1 (en) 2005-11-07 2006-04-12 Reverse reaction sintering of Si3N4/SiC composites
US11/279,461 2006-04-12

Publications (2)

Publication Number Publication Date
WO2007055776A2 true WO2007055776A2 (fr) 2007-05-18
WO2007055776A3 WO2007055776A3 (fr) 2007-11-22

Family

ID=38023736

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2006/033405 WO2007055776A2 (fr) 2005-11-07 2006-08-28 REACTION INVERSE DE FRITTAGE DE COMPOSITES Si3N4/SiC

Country Status (2)

Country Link
EP (1) EP1951486A4 (fr)
WO (1) WO2007055776A2 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115620847A (zh) * 2022-12-06 2023-01-17 中国空气动力研究与发展中心计算空气动力研究所 一种硅基复合材料烧蚀形貌的确定方法及相关装置
CN115772039A (zh) * 2022-12-14 2023-03-10 衡阳凯新特种材料科技有限公司 一种具有发热膜的氮化硅发热体的制备方法

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3193399A (en) * 1960-07-28 1965-07-06 Norton Co Siliconoxynitride bonded silicon carbide article and method
WO1987005597A1 (fr) * 1986-03-14 1987-09-24 Commonwealth Scientific And Industrial Research Or Procede de formage d'un produit en ceramique
DE3855544T2 (de) * 1987-04-10 1997-03-27 Hitachi Ltd Keramische Verbundwerkstoff und Verfahren zur Herstellung desselben
JPH0747507B2 (ja) * 1990-08-31 1995-05-24 日本碍子株式会社 窒化物結合ＳｉＣ耐火物
JP2974473B2 (ja) * 1991-10-30 1999-11-10 日本碍子株式会社 複合セラミックスおよびその製造法
JP4376579B2 (ja) * 2003-09-09 2009-12-02 日本碍子株式会社 窒化珪素結合ＳｉＣ耐火物及びその製造方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of EP1951486A4 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115620847A (zh) * 2022-12-06 2023-01-17 中国空气动力研究与发展中心计算空气动力研究所 一种硅基复合材料烧蚀形貌的确定方法及相关装置
CN115772039A (zh) * 2022-12-14 2023-03-10 衡阳凯新特种材料科技有限公司 一种具有发热膜的氮化硅发热体的制备方法

Also Published As

Publication number Publication date
WO2007055776A3 (fr) 2007-11-22
EP1951486A4 (fr) 2009-11-18
EP1951486A2 (fr) 2008-08-06

Similar Documents

Publication Publication Date Title
US7723247B2 (en) Method for pressurelessly sintering zirconium diboride/silicon carbide composite bodies to high densities
US4640903A (en) Silicon nitride sintered bodies and a method for producing the same
KR101160140B1 (ko) 지르코늄디보라이드-실리콘카바이드 복합소재의 제조방법
EP0385509B1 (fr) Procédé de production de matériaux composites céramiques
US8097548B2 (en) High-density pressurelessly sintered zirconium diboride/silicon carbide composite bodies and a method for producing the same
US7446066B1 (en) Reverse reaction sintering of Si3N4/SiC composites
JPH1149572A (ja) セラミックス複合粒子及びその製造方法
WO2007055776A2 (fr) REACTION INVERSE DE FRITTAGE DE COMPOSITES Si3N4/SiC
US7648675B2 (en) Reaction sintered zirconium carbide/tungsten composite bodies and a method for producing the same
JP4348429B2 (ja) 窒化ケイ素多孔体及びその製造方法
JPS6212663A (ja) Ｂ４ｃ質複合体およびその製造方法
JP3152790B2 (ja) 窒化珪素質焼結体の製造方法
JP3975016B2 (ja) 窒化珪素焼結体及びその製造方法
JPS6212664A (ja) Ｂ↓４ｃ質複合体の焼結方法
JP3570676B2 (ja) セラミックス多孔体及びその製造方法
EP0261065B1 (fr) Production d'articles céramiques incorporant une matière de remplissage poreuse
JP3318466B2 (ja) 窒化珪素質焼結体およびその製造方法
JPH0627029B2 (ja) 窒化珪素質焼結体及びその製造法
JPH0138075B2 (fr)
JP3667145B2 (ja) 窒化珪素質焼結体
JPS6344713B2 (fr)
JPH0772105B2 (ja) 窒化珪素質焼結体およびその製造方法
JPH06247771A (ja) 窒化ほう素複合材料およびその製造方法
JP3567001B2 (ja) 炭化珪素と窒化珪素の複合焼結体の製造方法
Naito PORE SIZE DISTRIBUTION DURING COMPACTION AND EARLY STAGE SINTERING OF Si3N4

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase in:

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2006802409

Country of ref document: EP