CN109251022A - The precinct laser sintering technology of the alumina oxide matrix porous ceramic shell of moltening mold castings - Google Patents

The precinct laser sintering technology of the alumina oxide matrix porous ceramic shell of moltening mold castings Download PDF

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CN109251022A
CN109251022A CN201811109236.3A CN201811109236A CN109251022A CN 109251022 A CN109251022 A CN 109251022A CN 201811109236 A CN201811109236 A CN 201811109236A CN 109251022 A CN109251022 A CN 109251022A
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ceramic shell
prefabricated component
weight
parts
mesh
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许庆彦
魏倩
许自霖
王润楠
钟江伟
杨聪
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Tsinghua University
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Tsinghua University
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    • 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
    • C04B35/16—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 silicates other than clay
    • C04B35/18—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 silicates other than clay rich in aluminium oxide
    • C04B35/185—Mullite 3Al2O3-2SiO2
    • 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
    • C04B35/64—Burning or sintering processes
    • 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
    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/0051—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof characterised by the pore size, pore shape or kind of porosity
    • C04B38/0054—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof characterised by the pore size, pore shape or kind of porosity the pores being microsized or nanosized
    • 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
    • C04B2235/65—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
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    • 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
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    • 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
    • C04B2235/665—Local sintering, e.g. laser sintering
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
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Abstract

The present invention provides the precinct laser sintering technologies of the alumina oxide matrix porous ceramic shell of moltening mold castings.Based on the gross mass of the ceramic shell, the mass percentage of mullite phase is not less than 60% in the ceramic shell.On the one hand, the precision of the ceramic shell is high, intensity is high, quality is stable, excellent in mechanical performance, and then can make when producing engine blade using the ceramic shell as mold, which is not susceptible to rupture and lead to leakage；On the other hand, the ceramic shell is with short production cycle, at low cost, it is easy to accomplish industrialization.

Description

The precinct laser sintering technology of the alumina oxide matrix porous ceramic shell of moltening mold castings
Technical field
The present invention relates to field of material technology, specifically, being related to the choosing of the alumina oxide matrix porous ceramic shell of moltening mold castings Area's laser sintering technology.
Background technique
The preparation method period of ceramic shell is long, at high cost at present, and it is poor to prepare resulting ceramic shell mechanical property, Unstable quality.
Thus, the relevant technologies of existing ceramic shell still have much room for improvement.
Summary of the invention
The present invention is directed to solve at least some of the technical problems in related technologies.
The present invention is the following discovery based on inventor and completes:
In the related art, the mechanical property of the ceramic shell of traditional Investment casting technology preparation is poor, and quality is unstable It is fixed, and the production cycle is long, at high cost, is difficult to control.After inventor has carried out a large amount of careful investigations and experimental study for this It was found that due to method itself, optimization is best anyway using method in the related technology when preparing ceramic shell Technological parameter, the mass percentage for preparing mullite phase in resulting ceramic shell is lower, thereby results in traditional It prepares in the method for ceramic shell, the mechanical property for preparing resulting ceramic shell is poor, unstable quality, it is difficult to meet ceramics The actual use demand of shell.
Based on this, inventor has broken correlation after having carried out a large amount of in-depth studies to the method for preparing ceramic shell Since ceramic shell is applied to field of aerospace technology, harsh for production technology and precinct laser sintering technology in technology Laser energy deficiency can not produce the general cognition of ceramic shell, it has unexpectedly been found that first be prepared using precinct laser sintering technology It carries out being sintered the prefabricated component again after prefabricated component improving significantly and prepares in resulting ceramic shell not come The mass percentage of stone phase.Further, process conditions, ginseng of the inventor to precinct laser sintering technology and sintering processes Number etc. has carried out further optimization, to obtain the pottery that precision is high, intensity is high, quality is stable, mechanical property is more excellent Porcelain shell, and then the ceramic shell will not occur to rupture and lead to leakage when producing engine blade as mold.
In view of this, an object of the present invention is to provide a kind of precision height, intensity is high, quality is stable, mechanical property It is excellent, as mold produce engine blade when be not susceptible to rupture and cause leakage, it is with short production cycle, at low cost, be easy to Realize the ceramic shell of industrialization.
In one aspect of the invention, the present invention provides a kind of ceramic shells.According to an embodiment of the invention, based on institute The gross mass of ceramic shell is stated, the mass percentage of mullite phase is not less than 60% in the ceramic shell.Inventors have found that On the one hand, the precision of the ceramic shell is high, intensity is high, quality is stable, excellent in mechanical performance, and then can make with the ceramics When shell produces engine blade as mold, which is not susceptible to rupture and lead to leakage；On the other hand, the ceramics The production cycle of shell can be as short as 4~5 days, it is at low cost, it is easy to accomplish industrialization, at the same be suitable for trial and error study.
According to an embodiment of the invention, the compressive strength of the ceramic shell is not less than 80MPa, the bullet of the ceramic shell Property modulus be not less than 1500MPa.
In another aspect of the invention, the present invention provides a kind of methods for preparing ceramic shell.It is according to the present invention Embodiment, this method comprises: precinct laser sintering is carried out to raw mixture, to obtain prefabricated component；By the prefabricated component into Row sintering processes, to obtain ceramic shell.Inventors have found that this method is simple, convenient, it is easy to accomplish, cost is relatively low, Production cycle can be as short as 4~5 days, it is easy to accomplish industrialization, while being suitable for trial and error and studying, and preparing resulting ceramic shell precision High, intensity height, quality stabilization, excellent in mechanical performance, and then can producing engine using the ceramic shell as mold When blade, which is not susceptible to rupture and lead to leakage.
According to an embodiment of the invention, the raw mixture includes: the Al of 35~60 parts by weight2O3；6~16 parts by weight Binder；The SiO of 24~59 parts by weight2。
According to an embodiment of the invention, the Al2O3With the SiO2Granularity be each independently 270~450 mesh.
According to an embodiment of the invention, the Al2O3With the SiO2Purity be not less than 99.0% each independently.
According to an embodiment of the invention, the binder includes epoxy resin ER12.
According to an embodiment of the invention, the raw mixture is by by the Al2O3, the binder and described SiO2It is stirred 12 under the speed conditions of 8~10r/min~obtain for 24 hours.
According to an embodiment of the invention, described be stirred is carried out using planetary three-dimensional hybrid equipment.
According to an embodiment of the invention, the precinct laser sintering meets at least one of the following conditions: lift height 0.10~0.20mm；16~24W of laser power, 3000~5000mm/s of scanning speed, 0.10~0.20mm of sweep span.
According to an embodiment of the invention, the sintering processes through the following steps that carry out: with 6~8 DEG C/min plus After hot rate is warming up to 800~1200 DEG C, 1450~1600 DEG C are warming up to the rate of heat addition of 3~5 DEG C/min, and 1450~ 20~40min is kept the temperature under the conditions of 1600 DEG C.
According to an embodiment of the invention, this method comprises: using planetary three-dimensional hybrid equipment, in the speed of mainshaft 8~ Under the conditions of 10r/min, air dielectric, by 35~60 parts by weight, the Al that granularity is 270~450 mesh2O3, the ring of 6~16 parts by weight Oxygen resin ER12 and 24~59 parts by weight, the SiO that granularity is 270~450 mesh2Mixing 12~for 24 hours, to obtain raw material mixing Object；In 16~24W of laser power, 3000~5000mm/s of scanning speed, 0.10~0.20mm of sweep span, lift height 0.10 Under conditions of~0.20mm, the raw mixture is subjected to precinct laser sintering, to obtain prefabricated component；With 6~8 DEG C/min The rate of heat addition prefabricated component is warming up to 800~1200 DEG C after, with the rate of heat addition of 3~5 DEG C/min by the prefabricated component It is warming up to 1450~1600 DEG C and keeps the temperature 20~40min, to obtain ceramic shell.
Detailed description of the invention
Fig. 1 shows the flow diagram of the method for preparing ceramic shell of one embodiment of the invention.
Fig. 2 a, Fig. 2 b, Fig. 2 c, Fig. 2 d show the operation principle schematic diagram of precinct laser sintering of the invention.
Fig. 3 shows the X ray diffracting spectrum of ceramic shell in the embodiment of the present invention 1.
Fig. 4 shows the electron scanning micrograph of ceramic shell in the embodiment of the present invention 1.
Fig. 5 shows the normal temperature compressed load-deformation curve of ceramic shell in the embodiment of the present invention 1.
Fig. 6 shows the high temperature compressed load-deformation curve of ceramic shell in the embodiment of the present invention 1.
Fig. 7 shows the X ray diffracting spectrum of ceramic shell in the embodiment of the present invention 2.
Fig. 8 shows the electron scanning micrograph of ceramic shell in the embodiment of the present invention 2.
Fig. 9 shows the normal temperature compressed load-deformation curve of ceramic shell in the embodiment of the present invention 2.
Figure 10 shows the high temperature compressed load-deformation curve of ceramic shell in the embodiment of the present invention 2.
Figure 11 shows the X ray diffracting spectrum of ceramic shell in the embodiment of the present invention 3.
Figure 12 shows the electron scanning micrograph of ceramic shell in the embodiment of the present invention 3.
Figure 13 shows the normal temperature compressed load-deformation curve of ceramic shell in the embodiment of the present invention 3.
Figure 14 shows the high temperature compressed load-deformation curve of ceramic shell in the embodiment of the present invention 3.
Appended drawing reference:
11: the first sheet submodel region, 12: the second sheet submodel region 99: laser 100: laser beam emitting device 200: laser deflection device 300: power spreading device 400: powder feed system 500: work system
Specific embodiment
The embodiment of the present invention is described below in detail.The embodiments described below is exemplary, and is only used for explaining this hair It is bright, and be not considered as limiting the invention.Particular technique or condition are not specified in embodiment, according to text in the art It offers described technology or conditions or is carried out according to product description.Reagents or instruments used without specified manufacturer, For can be with conventional products that are commercially available.
In one aspect of the invention, the present invention provides a kind of ceramic shells.According to an embodiment of the invention, based on institute The gross mass of ceramic shell is stated, the mass percentage of mullite phase is not less than 60% in the ceramic shell.Inventors have found that The ceramic shell prepares resulting ceramic shell compared to method in the related technology, due to the mass percentage of mullite phase Height, thus the precision of the ceramic shell is high, intensity is high, quality is stable, excellent in mechanical performance, and then can make with the ceramics When shell produces engine blade as mold, which is not susceptible to rupture and lead to leakage；On the other hand, the ceramics The production cycle of shell can be as short as 4~5 days, it is at low cost, it is easy to accomplish industrialization, at the same be suitable for trial and error study.
In some embodiments of the invention, the gross mass based on the ceramic shell, mullite in the ceramic shell The mass percentage of phase can be 60%, 62.4%, 70%, 80%, 88%, 90%, 95.4% etc..The ceramics as a result, The mass percentage of mullite phase in shell significantly improves, can be further such that the precision height of the ceramic shell, intensity High, quality stabilization, excellent in mechanical performance, and then can make when producing engine blade using the ceramic shell as mold, The ceramic shell is not susceptible to rupture and lead to leakage；On the other hand, the production cycle of the ceramic shell can be as short as 4~5 days, at This is low, it is easy to accomplish industrialization, while being suitable for trial and error and studying.
According to an embodiment of the invention, the compressive strength of the ceramic shell is not less than 80MPa, the bullet of the ceramic shell Property modulus be not less than 1500MPa.In some embodiments of the invention, the normal temperature compressed intensity of the ceramic shell can be 80MPa, 85MPa, 92MPa, 100MPa, 110MPa, 118MPa etc.；The high temperature compression strength of the ceramic shell can be 92MPa, 99MPa, 110MPa, 120MPa, 130MPa, 140MPa, 150MPa, 160MPa, 172MPa etc.；The ceramic shell Room temperature elasticity modulus can for 1500MPa, 1558MPa, 1600MPa, 1821MPa, 2000MPa, 2200MPa, 2400MPa, 2600MPa, 2834MPa etc.；The high-temperature elastic modulus of the ceramic shell can for 1600MPa, 1712MPa, 1800MPa, 1875MPa, 2000MPa, 2188MPa etc..The mass percentage of the mullite phase in the ceramic shell significantly improves as a result, Can be with further such that the precision of the ceramic shell be high, intensity is high, quality is stable, excellent in mechanical performance, and then can make When producing engine blade using the ceramic shell as mold, which is not susceptible to rupture and lead to leakage.
In another aspect of the invention, the present invention provides a kind of methods for preparing ceramic shell.It is according to the present invention Embodiment, a, Fig. 2 b, Fig. 2 c, Fig. 2 d referring to Figures 1 and 2, method includes the following steps:
S100: precinct laser sintering is carried out to raw mixture, to obtain prefabricated component.
According to an embodiment of the invention, the precinct laser sintering, which refers to, carries out prototype to the structure of the prefabricated component Afterwards, the technology of printing sintering is carried out.Before carrying out printing sintering to the raw mixture, it is necessary first to the prefabricated component Prototype is carried out, that is, designs the shape of the prefabricated component, printing sintering is carried out to the raw mixture so as to subsequent.? In some embodiments of the present invention, carrying out prototype to the raw mixture can be specially to use modeling software (UG/ Pro/E etc.) the design prefabricated component 3D model after, the 3D model file of the prefabricated component is converted into STL format, and to institute The 3D model for stating prefabricated component carries out hierarchy slicing processing, and the 3D model for carrying out the hierarchy slicing treated the prefabricated component is Multiple sheet submodels region (the case where below by taking two sheet submodel regions as an example, is illustrated, reference Fig. 2 d, including the One sheet submodel region 11 and the second sheet submodel region 12), each sheet submodel region has cutting section. It is conducive to subsequent carry out precinct laser sintering, as a result, to obtain the prefabricated component.
According to an embodiment of the invention, the printing sintering is dust feeder 400 referring to Fig. 2 a, Fig. 2 b, Fig. 2 c, Fig. 2 d According to powder feeding direction transferring raw material mixture, then the raw mixture is put down according to powdering direction using power spreading device 300 It is layered on the surface of work system 500, laser 99 is launched by laser beam emitting device 100, the control of computer scanning control system swashs The deflection of light-deflection apparatus 200, the laser deflection device 200 according to the first sheet submodel region 11 cutting section Profile sintering is scanned on the raw mixture, obtain the 11 (structural schematic diagram of the first sheet submodel region Referring to Fig. 2 b).After the first sheet submodel region 11 sintering obtained when prototype is completed, work system 500 Decline the height (structural schematic diagram reference Fig. 2 c) in a sheet submodel region, power spreading device 300 according to moving direction Tile one layer of uniform raw mixture on the surface in the first sheet submodel region 11 after the completion of having scanned sintering, And continue by the laser deflection device 200 according to the profile of the cutting section in the second sheet submodel region 12 described Sintering is scanned on raw mixture, to form the second sheet submodel region 12 (structural schematic diagram reference Fig. 2 d), After multiple sheet submodel regions are all so scanned sintering, the prefabricated component is obtained.Of the invention In other embodiments, it can also include powder system (not shown) of overflowing, be sintered after completion to collect each layer of scanning Remaining raw mixture.
In some embodiments of the invention, the laser beam emitting device 100 can be specially laser；The laser is inclined Rotary device 200 can be specially galvanometer；The power spreading device 300 can be powder-laying roller.Device is simple, convenient as a result, holds It easily realizes, cost is relatively low, it is easy to accomplish industrialized production.
According to an embodiment of the invention, the thickness in multiple sheet submodels region of the precinct laser sintering, that is, be layered Thickness can be 0.10~0.20mm.In some embodiments of the invention, the lift height can be specially 0.10mm, 0.12mm, 0.14mm, 0.16mm, 0.18mm, 0.20mm etc..Thus, it is possible to make the intensity height of the prefabricated component, precision high, And the efficiency of the precinct laser sintering can be made higher, to be conducive to the progress of subsequent technique.Lift height is too small, constituency Laser sintered depth is bigger, when may cause binder charing, the intensity and precision of the prefabricated component, and increasing forming Between；Lift height is excessive, and binder can occur part and soften, and the intensity of the prefabricated component and precision variation is caused (to need to illustrate , in an embodiment of the present invention, " prefabricated component " can be understood as " the first base " in material machine-shaping field, refer to described After raw mixture carries out precinct laser sintering, it is sintered the workpiece obtained before).
According to an embodiment of the invention, the laser power of the precinct laser sintering can be 16~24W.Of the invention In some embodiments, the laser power of the precinct laser sintering can be specially 16W, 18W, 20W, 22W, 24W etc..As a result, Intensity height, the precision of the prefabricated component can be made high, to be conducive to the progress of subsequent technique.Laser power is excessive, laser pair The heat of the raw mixture transmission is excessively high, will lead to the prefabricated component and is also easy to produce buckling deformation or bonding failure；Conversely, Laser power is too low, and the heat that laser transmits the raw mixture is relatively low, and the intensity of the prefabricated component is too low, or even cannot Molding.
According to an embodiment of the invention, the scanning speed of the precinct laser sintering can be 3000~5000mm/s.? In some embodiments of the present invention, the scanning speed of the precinct laser sintering can be specially 3000mm/s, 3500mm/s, 4000mm/s, 4500mm/s, 5000mm/s etc..Thus, it is possible to make the intensity height of the prefabricated component, precision high, and can make The efficiency for obtaining the precinct laser sintering is higher, to be conducive to the progress of subsequent technique.It is laser sintered when scanning speed is too low Time is long, and the heat that laser is transmitted to the raw mixture is high, easily leads to binder charing, intensity, the essence of the prefabricated component Degree is deteriorated, and reduces forming efficiency；Scanning speed is excessively high, and the laser sintered time is short, and laser is transmitted to the raw mixture Thermal Finite, binder solidification not exclusively, the intensity and precision of the prefabricated component are poor.
According to an embodiment of the invention, the sweep span of the precinct laser sintering can be 0.10~0.20mm.At this Invention some embodiments in, the sweep span of the precinct laser sintering can be specially 0.10mm, 0.12mm, 0.14mm, 0.15mm, 0.16mm, 0.18mm, 0.20mm etc..Thus, it is possible to make the intensity height of the prefabricated component, precision high, and can make The efficiency for obtaining the precinct laser sintering is higher, to be conducive to the progress of subsequent technique.Due in laser sintered processing, laser The spot diameter of beam be it is certain, when sweep span is too small, scanning times on unit area increase, and laser energy exported Height easily leads to binder scaling loss, and the prefabricated component is also easy to produce bending, deformation, causes the prefabricated component intensity, precision too low, and Extend molding time；Sweep span is excessive, and scan line lap is very little, the energy in the region between adjacent two scan lines It very little and is unevenly distributed, the mouldability of the prefabricated component is poor, and intensity is poor.
According to an embodiment of the invention, inventor the technical parameter of the precinct laser sintering has been carried out it is a large amount of careful Investigation and experimental verification, inventors have found that when the lift height is 0.10mm, laser power 20W, scanning speed are When 4000mm/s, sweep span are 0.15mm, the precision for preparing resulting prefabricated component can be made to reach and further increased, thus Further such that handling by follow-up sintering, the precision height of obtained ceramic shell, intensity is high, quality is stable, mechanical property reaches To best.
According to an embodiment of the invention, the raw mixture includes: the Al of 35~60 parts by weight2O3；6~16 parts by weight Binder；The SiO of 24~59 parts by weight2.In some embodiments of the invention, described in the raw mixture Al2O3Parts by weight can be for 35 parts by weight, 40 parts by weight, 45 parts by weight, 50 parts by weight, 55 parts by weight, 60 parts by weight etc.； The parts by weight of the binder can be 6 parts by weight, 8 parts by weight, 10 parts by weight, 12 parts by weight, 14 parts by weight, 16 parts by weight Deng；The SiO2Parts by weight can be 24 parts by weight, 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight, 50 weights Measure part, 55 parts by weight, 59 parts by weight etc..Proportion as a result, in the raw mixture is suitable, so that using of the present invention The ceramic shell that is formed of method in the content of mullite phase higher be possibly realized.
According to an embodiment of the invention, the Al2O3With the SiO2Granularity can be each independently 270~450 Mesh.In some embodiments of the invention, the Al2O3With the SiO2Granularity can each independently be specially 270 mesh, 300 mesh, 330 mesh, 360 mesh, 390 mesh, 420 mesh, 450 mesh etc..The Al as a result,2O3With the SiO2Granularity it is moderate, benefit In the molding of the prefabricated component, when carrying out precinct laser sintering to the raw mixture, the raw mixture is not susceptible to Bonding, results in steamed bun shape convex surface；It is conducive to the power spreading device in precinct laser sintering simultaneously to carry out the raw mixture Powdering.
According to an embodiment of the invention, the Al2O3With the SiO2Purity be not less than 99.0% each independently, In some embodiments of the present invention, the Al2O3With the SiO2Purity can be each independently 99.0%, 99.9%, 99.99% etc..Al in the raw mixture as a result,2O3And SiO2Purity it is higher, may further ensure that be formed The better performances of the ceramic shell.
According to an embodiment of the invention, binder includes epoxy resin ER12.Material source is extensive as a result, is easy to get, cost It is lower, and caking property is preferable, and the mechanical properties such as compressive strength and the elasticity modulus of the ceramic shell can be made further to mention It is high.
According to an embodiment of the invention, the raw mixture preparation method can be the Al2O3, the binder With the SiO2It is stirred 12 under the speed conditions of 8~10r/min~for 24 hours.In some embodiments of the invention, by institute State Al2O3, the binder and the SiO2The revolving speed being stirred can be specially 8r/min, 9r/min, 10r/min etc.；It will The Al2O3, the binder and the SiO2The time being stirred can be 12h, 14h, 16h, 18h, 20h, 22h, for 24 hours Deng.The mixed effect of each component is preferable in the raw mixture as a result, when the time being stirred is 12h, mixes It is even (after mixing raw mixture, repeatedly to be sampled from raw mixture, in microscope than reachable by 97% or more Under it is for statistical analysis, thus obtain mix ratio)；When incorporation time is extended to for 24 hours, mix than up to 99%.
In some embodiments of the invention, described be stirred can be using the progress of planetary three-dimensional hybrid equipment , the revolving speed is the speed of mainshaft of the planetary three-dimensional hybrid equipment.Device is simple, convenient as a result, is easy real Existing, cost is relatively low, it is easy to accomplish industrialized production.
S200: the prefabricated component is sintered, to obtain ceramic shell.
It is warming up to according to an embodiment of the invention, the sintering processes can be by the rate of heat addition with 6~8 DEG C/min After 800~1200 DEG C, 1450~1600 DEG C are warming up to the rate of heat addition of 3~5 DEG C/min, and under the conditions of 1450~1600 DEG C What the step of keeping the temperature 30min carried out.Specifically, in some embodiments of the invention, the sintering processes can be by with 6 DEG C/min, 7 DEG C/min or 8 DEG C/min the rate of heat addition be warming up to 800 DEG C, 900 DEG C, 1000 DEG C, 1100 DEG C or 1200 After DEG C, with the rate of heat addition of 3 DEG C/min, 3 DEG C/min or 5 DEG C/min be warming up to 1450 DEG C, 1500 DEG C, 1550 DEG C or 1600 DEG C, and the step of keeping the temperature 20min, 30min or 40min at such a temperature carries out.Thus, it is possible to make described pre- For product when being sintered, the shrinking percentage of prefabricated component is smaller, and the raw mixture for forming the prefabricated component occurs diffusion, moves It moves, the stomata in raw mixture disappears, and a large amount of fine and close mullite phases is generated, thus further such that the ceramic shell Precision is high, intensity is high, quality is stable, excellent in mechanical performance, and then can producing hair using the ceramic shell as mold When motivation blade, which is not susceptible to rupture and lead to leakage.
The embodiment of the present invention is described below in detail.
Embodiment 1
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 40 parts by weight, grain Degree is the Al of 270 mesh2O3(purity: mass fraction >=99.0%), 60 parts by weight, the SiO that granularity is 270 mesh2(purity: quality point Number >=99.0%), 8 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 16W, scanning speed 5000mm/ Under conditions of s, sweep span 0.10mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 8 DEG C/min, with the rate of heat addition of 3 DEG C/min by prefabricated component It is warming up to 1450 DEG C and keeps the temperature 30min, to obtain ceramic shell.
Fig. 3 is the X ray diffracting spectrum that the present embodiment prepares resulting ceramic shell.It can be seen that main phase is orthogonal The mullite phase of crystalline form, secondary phase are the cubic cristobalite phase of crystalline form and the quartzy phase of hexagonal crystal shape, whole in raw mixture Al2O3And SiO2Generate mullite phase (3Al2O3·2SiO2), remainder SiO2Crystalline form occurs in the high temperature process to turn Become, is cristobalite phase by quartzy phase transition.Can be calculated, mullite phase, quartzy phase, cristobalite phase mass percentage successively It is 62.4%, 12.7%, 25.0%.
Fig. 4 is the scanning electron micrograph that the present embodiment prepares resulting ceramic shell.It can be seen that the ceramic mould Shell is porous structure, and open pore size is between 10~50 μm.
The Mechanics Performance Testing of ceramic shell:
Using the mechanical property of heat simulating tester (Gleeble 1500D) test ceramic shell, fixed drafts is The 20% of ceramic shell height, strain rate 10-3/s。
Fig. 5 is the normal temperature compressed load-deformation curve that the present embodiment prepares resulting ceramic shell, ceramic shell performance For linear elasticity, within the scope of small strain, stress linearly increases with the increase of strain, after reaching maximum breaking strength, immediately Occur defeated and dispersed.As seen from the figure, the normal temperature compressed intensity of the ceramic shell is 85MPa, and room temperature elasticity modulus is 1558MPa.
Fig. 6 is that the present embodiment prepares compressive stress strain curve of the resulting ceramic shell under 900 DEG C of test conditions. As seen from the figure, the high temperature compression strength of the ceramic shell is 92MPa, high-temperature elastic modulus 1712MPa.
Embodiment 2
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 10r/min, air dielectric, by 48 parts by weight, grain Degree is the Al of 325 mesh2O3(purity: mass fraction >=99.0%), 52 parts by weight, the SiO that granularity is 325 mesh2(purity: quality point Number >=99.0%), 12 parts by weight, the epoxy resin ER12 that granularity is 350 mesh are mixed for 24 hours, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 18W, scanning speed 4000mm/ Under conditions of s, sweep span 0.15mm, lift height 0.15mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 3 DEG C/min by prefabricated component It is warming up to 1550 DEG C and keeps the temperature 30min, to obtain ceramic shell.
Fig. 7 is the X ray diffracting spectrum that the present embodiment prepares resulting ceramic shell.It can be seen that at 1550 DEG C, The object phase composition of the ceramic shell is mullite phase and cristobalite phase, can't detect the presence of quartzy phase, at the same 2 θ=18~ There is steamed bun peak appearance within the scope of 26 °, illustrates to form part amorphous phase in the ceramic shell.It is calculated, in the ceramic shell The mass percentage of mullite phase and cristobalite phase is respectively 88.0% and 12.0%, illustrates whole quartz phase and part side Quartzy mutually to become vitreous silica at 1550 DEG C, in cooling procedure, remaining cristobalite mutually becomes low form from high temperature modification It remains, vitreous silica forms amorphous phase SiO2It remains.
Fig. 8 is the scanning electron micrograph that the present embodiment prepares resulting ceramic shell.It can be seen that in this technique Under the conditions of, the size of open pore is at 40~150 μm, and the open pore compared with embodiment 1 becomes large-sized, and stomatal number amount becomes smaller.
The Mechanics Performance Testing of ceramic shell:
Using the mechanical property of heat simulating tester (Gleeble 1500D) test ceramic shell, fixed drafts is The 20% of ceramic shell height, strain rate 10-3/s。
Fig. 9 is the normal temperature compressed load-deformation curve that the present embodiment prepares resulting ceramic shell, the room temperature pressure of the product Stress under compression-strain curve is similar with embodiment 1, and linear elasticity is shown as within the scope of small strain, and stress is in line with the increase of strain Property increase, after reaching maximum breaking strength, be broken immediately, normal temperature compressed intensity is 92MPa, and room temperature elasticity modulus is 1821MPa can have found with Fig. 5 of embodiment 1 comparison, and the raising of temperature can increase the ceramic shell to a certain degree when sintering processes Normal temperature compressed intensity.
Figure 10 is that the present embodiment prepares compressive stress strain curve of the resulting ceramic shell under 900 DEG C of test conditions. As seen from the figure, the high temperature compression strength of the ceramic shell is 99MPa, high-temperature elastic modulus 1875MPa.
Embodiment 3
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
Figure 11 is the X ray diffracting spectrum that the present embodiment prepares resulting ceramic shell.It can be seen that at 1600 DEG C Under, the object phase composition of the ceramic shell is mullite phase and cristobalite phase, be can be calculated, the quality of mullite phase and cristobalite phase Percentage composition is respectively 95.4% and 4.6%, and dynamic, unordered cristobalite mutually continue to convert to vitreous silica, in cooling procedure Middle vitreous silica is changed into amorphous phase SiO2。
Figure 12 is the scanning electron micrograph that the present embodiment prepares resulting ceramic shell.It can be seen that 1600 At DEG C, the open pore of the ceramic shell connects into three-dimensional network, more densifies.
The Mechanics Performance Testing of ceramic shell:
Using the mechanical property of heat simulating tester (Gleeble 1500D) test ceramic shell, fixed drafts is The 20% of ceramic shell height, strain rate 10-3/s。
Figure 13 is the normal temperature compressed load-deformation curve that the present embodiment prepares resulting ceramic shell, in small strain range Interior, which shows as linear elasticity, and room temperature load-deformation curve linearly increases, and after reaching maximum breaking strength, sends out immediately Raw brittle fracture, normal temperature compressed intensity are 118MPa, elasticity modulus 2834MPa.With Fig. 5 and embodiment 2 of embodiment 1 Fig. 9 is compared, and the normal temperature compressed intensity and elasticity modulus of the ceramic shell of the present embodiment have certain amplitude raising, this is because not The content for carrying out stone phase increases and the development of the crystalline form of mullite phase is more completely caused.
Figure 14 is that the present embodiment prepares compressive stress strain curve of the resulting ceramic shell under 900 DEG C of test conditions. As seen from the figure, the high temperature compression strength of the ceramic shell is 172MPa, high-temperature elastic modulus 2188MPa.
Embodiment 4
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4000mm/ Under conditions of s, sweep span 0.15mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 5
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 15W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 6
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 25W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 7
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 2500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 8
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 5500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 9
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.80mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 10
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.22mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 11
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.80mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 12
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.22mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity of prefabricated component obtained in the present embodiment is high, precision is high, to be conducive to the progress of subsequent technique, and then is convenient for Obtain ceramic shell.
Embodiment 13
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 5 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The normal of the ceramic shell that the present embodiment obtains, high temperature compression strength are lower, and (slow heating can promote crystal grain to grow up, and hinder Hinder the progress of sintering densification).
Embodiment 14
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 9 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The normal of the ceramic shell that the present embodiment obtains, high temperature compression strength, elasticity modulus are higher.
Embodiment 15
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 750 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity for the ceramic shell that the present embodiment obtains is lower, because of low first burning temperature not coming of causing to generate in tissue Stone nucleus is less, is unfavorable for the growth and development of later period mullite crystal, also has led to the low-intensity of ceramic shell.
Embodiment 16
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1250 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The normal of the ceramic shell that the present embodiment obtains, elevated temperature strength are poor.
Embodiment 17
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 2 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity for the ceramic shell ceramic shell that the present embodiment obtains is poor, easily leads to shell and generates a fairly large number of hole Gap, and extend sintering time.
Embodiment 18
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 6 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity for the ceramic shell that the present embodiment obtains is poor, occurs greatly because too fast heating rate results in shell Temperature gradient and stress gradient, easily lead to shell and crack and deform.
Embodiment 19
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1400 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity for the ceramic shell that the present embodiment obtains is lower, and the hole quantity of ceramic shell is more, mullite crystal hair It educates not exclusively.
Embodiment 20
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1650 DEG C and keeps the temperature 30min, to obtain ceramic shell.
The intensity for the ceramic shell that the present embodiment obtains is reduced compared with embodiment 3, but shell body shrinking percentage deteriorates, in tissue More liquid phase can be generated, its mechanical property is weakened.
Embodiment 21
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 15min, to obtain ceramic shell.
The intensity for the ceramic shell that the present embodiment obtains is poor, and because its soaking time is shorter, mullite crystal development is endless Entirely.
Embodiment 22
Using planetary three-dimensional hybrid equipment, under the conditions of speed of mainshaft 8r/min, air dielectric, by 55 parts by weight, grain Degree is the Al of 400 mesh2O3(purity: mass fraction >=99.0%), 45 parts by weight, the SiO that granularity is 400 mesh2(purity: quality point Number >=99.0%), 10 parts by weight, the epoxy resin ER12 mixing 12h that granularity is 350 mesh, to obtain raw mixture.
After the 3D model for designing the prefabricated component using UG modeling software, the 3D model file of the prefabricated component is converted into STL format, and hierarchy slicing processing is carried out to the 3D model of the prefabricated component.In laser power 20W, scanning speed 4500mm/ Under conditions of s, sweep span 0.20mm, lift height 0.10mm, the raw mixture is subjected to printing sintering, is obtained prefabricated Part.
After prefabricated component is warming up to 1000 DEG C with the rate of heat addition of 6 DEG C/min, with the rate of heat addition of 5 DEG C/min by prefabricated component It is warming up to 1600 DEG C and keeps the temperature 50min, to obtain ceramic shell.
The body shrinking percentage for the ceramic shell that the present embodiment obtains is bigger.
Comparative example 1
Traditional Investment casting technology prepares resulting ceramic shell.
The mass percentage of mullite phase is 22%~35%.
Normal temperature compressed intensity is 25MPa~30MPa, and room temperature elasticity modulus is 460MPa~700MPa.
High temperature compression strength under 700 DEG C of test conditions is 45MPa~60MPa, high-temperature elastic modulus be 700MPa~ 900MPa。
In the description of this specification, reference term " one embodiment ", " some embodiments ", " example ", " specifically show The description of example " or " some examples " etc. means specific features, structure, material or spy described in conjunction with this embodiment or example Point is included at least one embodiment or example of the invention.In the present specification, schematic expression of the above terms are not It must be directed to identical embodiment or example.Moreover, particular features, structures, materials, or characteristics described can be in office It can be combined in any suitable manner in one or more embodiment or examples.In addition, without conflicting with each other, the skill of this field Art personnel can tie the feature of different embodiments or examples described in this specification and different embodiments or examples It closes and combines.
Although the embodiments of the present invention has been shown and described above, it is to be understood that above-described embodiment is example Property, it is not considered as limiting the invention, those skilled in the art within the scope of the invention can be to above-mentioned Embodiment is changed, modifies, replacement and variant.

Claims (8)

1. a kind of ceramic shell, which is characterized in that the gross mass based on the ceramic shell, mullite phase in the ceramic shell Mass percentage be not less than 60%.
2. ceramic shell according to claim 1, which is characterized in that the compressive strength of the ceramic shell is not less than The elasticity modulus of 80MPa, the ceramic shell are not less than 1500MPa.
3. a kind of method for preparing ceramic shell characterized by comprising
Precinct laser sintering is carried out to raw mixture, to obtain prefabricated component；
The prefabricated component is sintered, to obtain ceramic shell.
4. according to the method described in claim 3, it is characterized in that, the raw mixture includes:
The Al of 35~60 parts by weight2O3；
The binder of 6~16 parts by weight；
The SiO of 24~59 parts by weight2,
Optional, the Al2O3With the SiO2Granularity be each independently 270~450 mesh,
Optional, the Al2O3With the SiO2Purity be not less than 99.0% each independently,
Optional, the binder includes epoxy resin ER12.
5. according to the method described in claim 4, it is characterized in that, the raw mixture is by by the Al2O3, it is described Binder and the SiO2It is stirred 12 under the speed conditions of 8~10r/min~obtain for 24 hours,
Optional, described be stirred is carried out using planetary three-dimensional hybrid equipment.
6. according to the method described in claim 3, it is characterized in that, the precinct laser sintering meet the following conditions at least it One:
0.10~0.20mm of lift height；16~24W of laser power, 3000~5000mm/s of scanning speed, sweep span 0.10 ~0.20mm.
7. according to the method described in claim 3, it is characterized in that, the sintering processes through the following steps that carry out:
After being warming up to 800~1200 DEG C with the rate of heat addition of 6~8 DEG C/min, it is warming up to the rate of heat addition of 3~5 DEG C/min 1450~1600 DEG C, and 20~40min is kept the temperature under the conditions of 1450~1600 DEG C.
8. according to the method described in claim 3, it is characterised by comprising:
Using planetary three-dimensional hybrid equipment, under the conditions of 8~10r/min of the speed of mainshaft, air dielectric, by 35~60 weight Part, the Al that granularity is 270~450 mesh2O3, the epoxy resin ER12 of 6~16 parts by weight and 24~59 parts by weight, granularity are 270~ The SiO of 450 mesh2Mixing 12~for 24 hours, to obtain raw mixture；
In 16~24W of laser power, 3000~5000mm/s of scanning speed, 0.10~0.20mm of sweep span, lift height Under conditions of 0.10~0.20mm, the raw mixture is subjected to precinct laser sintering, to obtain prefabricated component；
After the prefabricated component is warming up to 800~1200 DEG C with the rate of heat addition of 6~8 DEG C/min, with the heating of 3~5 DEG C/min The prefabricated component is warming up to 1450~1600 DEG C and keeps the temperature 20~40min by rate, to obtain ceramic shell.
CN201811109236.3A 2018-09-19 2018-09-21 The precinct laser sintering technology of the alumina oxide matrix porous ceramic shell of moltening mold castings Pending CN109251022A (en)

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