CN113698225A

CN113698225A - Ceramic load bearing board and preparation method thereof

Info

Publication number: CN113698225A
Application number: CN202110988490.0A
Authority: CN
Inventors: 詹海林; 陈初升
Original assignee: University of Science and Technology of China USTC
Current assignee: Chen Chusheng; University of Science and Technology of China USTC
Priority date: 2021-08-26
Filing date: 2021-08-26
Publication date: 2021-11-26
Anticipated expiration: 2041-08-26
Also published as: CN113698225B

Abstract

The invention provides a ceramic setter plate and a preparation method thereof. The invention provides a ceramic setter plate, wherein a plate body comprises a gradient straight hole layer; the gradient straight hole layer comprises a plurality of gradient straight holes distributed in a honeycomb shape, the axial direction of the hole channel is the thickness direction of the plate body, and the aperture of each straight hole is changed along the axial direction in a gradient manner. The ceramic setter plate with the structure provided by the invention has the advantages of high porosity, good air permeability and mechanical strength meeting the application requirements.

Description

Ceramic load bearing board and preparation method thereof

Technical Field

The invention relates to the field of ceramics, in particular to a ceramic load bearing plate and a preparation method thereof.

Background

The co-fired ceramic technology which rises in recent years, including LTCC, MLCC and HTCC, is widely applied to the field of a plurality of military and civil ceramic functional devices due to the characteristics of low cost, multi-layer layout, light weight, high performance, high integration and the like of products. The porous backing plate is a base material which must be used in the co-firing and post-firing processes of the co-fired ceramic, and the porous backing plate is required to have high air permeability, small surface roughness and sufficient mechanical strength.

The current preparation processes of setter plates mainly comprise dry pressing molding (CN101767991A), casting molding (CN110330358A), casting molding (CN103086737A) and the like. The preparation methods mainly provide pores in the setter plate by particle accumulation or adding pore-forming agents, pores produced by the method are difficult to ensure communication, so that the effect of high air permeability is difficult to achieve, and in addition, a large amount of pore-forming agents are added, so that the sintering difficulty of the product is increased, and the setter plate is not suitable for mass production. In order to meet the performance requirements, only special raw materials such as ceramic fibers can be selected, the characteristics of basic fibers are adopted, the porosity of the fiber board is high, and therefore the air permeability is good, but the price of the fiber raw materials is high, and the mass production is not facilitated.

Disclosure of Invention

In view of this, the invention provides a ceramic setter plate and a method for manufacturing the same. The ceramic setter plate provided by the invention can effectively improve the porosity and mechanical strength of the setter plate.

The invention provides a ceramic setter plate, wherein a plate body comprises a gradient straight hole layer;

the gradient straight hole layer comprises a plurality of gradient straight holes distributed in a honeycomb shape, the axial direction of the hole channel is the thickness direction of the plate body, and the aperture of each straight hole is changed along the axial direction in a gradient manner.

Preferably, in the gradient straight hole, the size of each straight hole is independently selected from: the aperture of the thin end is 0.1-10 μm, the aperture of the thick end is 50-500 μm, and the length of the pore channel is 0.1-5 mm.

Preferably, the plate body comprises a gradient straight hole layer and a capillary hole layer;

the capillary hole layer comprises a plurality of capillary holes.

Preferably, in the capillary hole layer, the pore size of the plurality of capillary holes is independently selected from: 0.1 to 80 μm.

Preferably, the plate body comprises a first plate body and a second plate body which are superposed and compounded;

the first plate body comprises a gradient straight hole layer;

the second plate body comprises a gradient straight hole layer and a capillary hole layer;

wherein the thin end surface in the gradient straight hole layer of the first plate body is in contact with the thin end surface in the gradient straight hole layer of the second plate body;

the thin end surface refers to the side of the gradient straight hole layer close to the thin end of the straight hole.

The invention also provides a preparation method of the ceramic setter plate in the technical scheme, which comprises the following steps:

a) preparing ceramic slurry A and sacrificial slurry XS;

the ceramic slurry A comprises the following components:

the ceramic raw material is prepared from a ceramic raw material,

the mass of the binder accounts for 3-10 wt% of the mass of the ceramic raw material;

a dispersant, wherein the mass of the dispersant accounts for 0.5 wt% -5 wt% of the mass of the ceramic raw material;

the pore-forming agent accounts for 5-30% of the volume of the ceramic raw material;

the mass of the solvent accounts for 30-60 wt% of the sum of the mass of the ceramic raw material and the mass of the pore-forming agent;

mixing a ceramic raw material, a binder, a dispersant, a pore-forming agent and a solvent to obtain ceramic slurry A;

the sacrificial slurry XS comprises the following components:

the sacrificial material is a powder material which can be discharged by sintering and is insoluble in the solvent;

mixing a sacrificial material, a binder, a dispersant and a solvent to obtain sacrificial slurry XS;

b) tape casting:

carrying out double-layer tape casting on the ceramic slurry A and the sacrificial slurry XS to obtain a material belt

c) And (3) curing:

the material belt is

Placing in water for curing to obtain wet blank

d) Wet blank treatment:

for the wet blank

Drying and maintaining to obtain green body

e) And (3) sintering:

to the green body

Sintering to obtain a ceramic setter plate A;

in the obtained ceramic setter plate A, the plate body comprises a gradient straight hole layer.

a) preparing ceramic slurry A and ceramic slurry B;

the ceramic slurry B comprises the following components:

the ceramic raw material is prepared from a ceramic raw material,

mixing a ceramic raw material, a binder, a dispersant, a pore-forming agent and a solvent to obtain ceramic slurry B;

b) tape casting:

carrying out double-layer tape casting on the ceramic slurry A and the ceramic slurry B to obtain a material belt

c) And (3) curing:

the material belt is

Placing in water for curing to obtain wet blank

d) Wet blank treatment:

for the wet blank

Drying and maintaining to obtain green body

e) And (3) sintering:

to the green body

Sintering to obtain the ceramic setter plate

The obtained ceramic setter plate

In, the plate body includes gradient straight hole layer and capillary pore layer.

Preferably, in the ceramic slurry a:

the ceramic raw material is ceramic powder and/or ceramic fiber;

the ceramic material is selected from one or more of alumina, zirconia, silica, titania, magnesia, kaolin, calcium carbonate, silicon carbide, talc, feldspar, cordierite, diatomite, mullite and boehmite;

the binder is selected from one or more of PESF, PES and PVB;

the dispersing agent is PVP and/or DSP;

the pore-forming agent is one or more of starch, graphite and wood chips;

the solvent is one or more selected from NMP, DMAc and DMSO.

Preferably, in the ceramic slurry B:

the ceramic raw material is ceramic powder and/or ceramic fiber;

the binder is selected from one or more of PESF, PES and PVB;

the dispersing agent is PVP and/or DSP;

the pore-forming agent is one or more of starch, graphite and wood chips;

the solvent is one or more selected from NMP, DMAc and DMSO.

Preferably, in the sacrificial slurry XS:

the sacrificial material is selected from one or more of graphite, starch and wood chips;

the binder is selected from one or more of PESF, PES and PVB;

the dispersing agent is PVP and/or DSP;

the solvent is one or more selected from NMP, DMAc and DMSO.

The ceramic setter plate provided by the invention has the advantages that the gradient straight holes distributed in a honeycomb shape are formed in the plate body, the axial direction of the pore channel is the thickness direction of the plate body, and the aperture of the straight holes changes along the axial gradient. The ceramic setter plate with the structure provided by the invention can effectively improve the porosity of the setter plate, the special pore structure can increase the air permeability of the setter plate, and the mechanical strength can meet the application requirements.

Experimental results show that the ceramic setter plate provided by the invention has the porosity of more than 55% and the air permeability of 8500m³/m²H.bar or more, and the three-point bending strength is 9.5MPa or more.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a schematic cross-sectional structural view of a first ceramic setter plate according to the present invention;

FIG. 2 is a schematic perspective view of a first ceramic setter plate according to the present invention;

FIG. 3 is a schematic cross-sectional view of a second ceramic setter plate according to the present invention;

FIG. 4 is a schematic perspective view of a second ceramic setter plate according to the present invention;

FIG. 5 is a schematic cross-sectional view of a third ceramic setter plate according to the present invention;

FIG. 6 is a schematic perspective view of a third ceramic setter plate according to the present invention;

FIG. 7 is an optical microscope photograph of a cross section of the ceramic setter obtained in example 3;

FIG. 8 is a schematic view of the honeycomb surface of the ceramic setter plate obtained in example 3;

FIG. 9 is a schematic view of the smooth surface of the ceramic setter plate obtained in example 3;

FIG. 10 is a schematic cross-sectional view of a graded straight hole layer in a ceramic setter plate.

Detailed Description

Regarding the first ceramic setter plate provided by the present invention:

the invention provides a first ceramic setter plate, which comprises: a gradient straight orifice layer.

Referring to fig. 1 and fig. 2, fig. 1 is a schematic cross-sectional structure diagram of a first ceramic setter plate provided by the present invention, and fig. 2 is a schematic perspective structure diagram of the first ceramic setter plate provided by the present invention; the first ceramic setter plate structure is marked as type A. Wherein, 1 is a plate body, 101 is a gradient straight hole (101a is a thin end, 101b is a thick end), 102 is a capillary hole, 103 is a first surface, and 104 is a second surface.

In the invention, the plate body of the ceramic setter plate comprises a gradient straight hole layer, and the gradient straight hole layer comprises a plurality of gradient straight holes which are distributed in a honeycomb shape. The gradient straight hole is a hollow pipe structure (namely a communicating hole), the axial direction of the pore channel is the thickness direction of the plate body, and the aperture of the straight hole changes along the axial gradient. The number of the gradient straight holes can be more than 1.

Wherein:

the gradient straight holes are distributed in a honeycomb shape, the axial direction of the pore channel is the thickness direction of the plate body, and the aperture of the straight holes changes along the axial gradient. In fig. 1-2, the gradient straight hole is only used to show the general shape of the gradient straight hole, and the sidewall thereof is relatively smooth, and in the actual product, the sidewall of the gradient straight hole is not completely smooth due to the straight hole structure formed by the reaction of the raw materials. Distribution of gradient straight holes referring to fig. 10, fig. 10 is a schematic cross-sectional view of a gradient straight hole layer in a ceramic setter plate, wherein black circles represent each gradient straight hole, and the gradient straight holes are distributed in a honeycomb shape.

In the plurality of gradient straight holes, the aperture of each straight hole changes in a gradient manner along the axial direction of the pore channel (namely the thickness direction of the plate body), namely, the aperture of each straight hole changes in a gradient manner from the upper surface to the lower surface of the plate body (the upper surface and the lower surface are not limited by special directions, one surface is the upper surface, and the other surface is naturally the lower surface). The gradient can be gradually increased or decreased, for example, the aperture diameter of each straight hole is gradually increased from the first surface to the second surface along the thickness direction of the plate body; if the direction from the second surface to the first surface is reversed, the aperture diameter of each straight hole is gradually reduced.

The gradient straight holes have gradient pore diameters, so that each gradient straight hole comprises a thin end and a thick end, which is shown in fig. 1, wherein 101a is the thin end, and 101b is the thick end. In the present invention, the size of each of the plurality of gradient straight holes is independently selected from: the aperture of the thin end is 0.1-10 μm, the aperture of the thick end is 50-500 μm, and the length of the pore channel is 0.1-5 mm. In the invention, the plate body of the ceramic setter plate comprises a first surface and a second surface, wherein the gradient straight hole penetrates through the two surfaces, but the gradient straight hole penetrates through the two surfaces in a microscopic view because the aperture of the gradient straight hole is smaller, but holes cannot be seen by naked eyes on the upper surface and the lower surface of the plate body in a macroscopic view, and the plate body is still a compact plate body.

In the present invention, the gradient straight-hole layer further includes a plurality of capillary holes, see fig. 1 and 2, wherein 102 is a capillary hole. The capillary holes are distributed in the matrix space except for the gradient straight holes, such as being sandwiched between the gradient straight holes. In the invention, the pore diameter of each capillary pore is independently selected from 0.1-80 μm.

In the invention, the thickness of the first ceramic setter plate is preferably 0.5-5 mm.

Regarding the second ceramic setter plate provided by the present invention:

the invention provides a second ceramic setter plate, which comprises: gradient straight pore layer and capillary pore layer.

Referring to fig. 3 and 4, fig. 3 is a schematic cross-sectional structure diagram of a second ceramic setter plate provided by the present invention, and fig. 4 is a schematic perspective structure diagram of the second ceramic setter plate provided by the present invention; the second ceramic setter plate structure is marked as

And (4) molding. Wherein 2 is a plate body, 2-z is a gradient straight hole layer, 2-m is a capillary hole layer, 201 is a gradient straight hole, 202z and 202m are capillary holes, 203 is a first surface, and 204 is a second surface.

In fig. 3-4, the dashed line is used as a boundary, the gradient straight pore layer is above the dashed line, and the capillary pore layer is below the dashed line. Wherein, the structure and the straight hole size of the gradient straight hole layer 2-z are the same as those in the first ceramic setter plate in the above technical solution, and are not described herein again.

In the present invention, the capillary hole layer 2-m includes only capillary hole-like pores, and does not include gradient straight hole-like pores. In the invention, in the capillary hole layers 2-m, the pore diameters of a plurality of capillary holes 202m are independently selected from: 0.1 to 80 μm.

In the second ceramic setter plate, the total thickness of the plate body is 0.5-5 mm; wherein, the thickness of the gradient straight hole layer accounts for 10 to 90 percent of the total thickness of the plate body.

Regarding the third ceramic setter plate provided by the present invention:

the third ceramic setter plate provided by the invention comprises: the first plate body and the second plate body.

Referring to fig. 5 and 6, fig. 5 is a schematic cross-sectional structure diagram of a third ceramic setter plate provided by the present invention, and fig. 6 is a schematic perspective structure diagram of the third ceramic setter plate provided by the present invention; the third ceramic setter plate structure is marked as

And (4) molding. 1 is a first plate body, 101 is a gradient straight hole, 102 is a capillary hole, 103 is a first surface of the first plate body, and 104 is a second surface of the first plate body; 2 is a second plate body, 2-z is a gradient straight hole layer, 2-m is a capillary hole layer, 201 is a gradient straight hole, 202z and 202m are capillary holes, 203 is a first surface of the second plate body, and 204 is a second surface of the second plate body.

In the invention, the first plate body comprises a gradient straight hole layer. The structure, the size of the straight hole, the thickness of the plate body and the like of the gradient straight hole layer are the same as those of the first ceramic setter plate in the technical scheme, and are not described in detail herein.

In the invention, the second plate body comprises a gradient straight hole layer and a capillary hole layer. The structure, the size and the like of the gradient straight hole layer and the capillary hole layer in the second plate body are consistent with those in the second ceramic setter plate in the technical scheme, and are not described in detail herein.

In the invention, the thin end surface in the gradient straight hole layer of the first plate body is contacted with the thin end surface in the gradient straight hole layer of the second plate body; wherein, the thin end surface refers to the side of the gradient straight hole layer close to the thin end of the straight hole. Referring to fig. 5-6, the first surface 103 of the first plate is in contact with the first surface 203 of the second plate.

With respect to other ceramic setter plates provided by the present invention:

the invention also provides another ceramic setter plate, comprising: two first ceramic setter plates; wherein the thin end surfaces in the gradient straight hole layers of the two first ceramic setter plates are in contact.

The invention also provides another ceramic setter plate, comprising: two second ceramic setter plates; wherein the thin end surfaces in the gradient straight hole layers of the two second ceramic setter plates are in contact.

The invention also provides other ceramic setter plates, comprising: at least one of the two plate bodies comprises a gradient straight hole layer; the structure of the gradient straight hole layer is the same as that in the foregoing technical solution, and is not described herein again.

The ceramic setter plate provided by the invention has the advantages that a gradient straight hole structure is formed in the plate body, a plurality of gradient straight holes are distributed in a honeycomb shape, the axial direction of a pore passage is the thickness direction of the plate body, and the pore diameter of each straight hole is changed along the axial direction in a gradient manner. The ceramic setter plate with the structure provided by the invention can effectively improve the porosity of the setter plate, and the special hole structure is an effective hole capable of increasing the air permeability, so that the air permeability of the setter plate can be effectively improved, and the mechanical strength of the ceramic setter plate can be improved.

The invention provides a preparation method of a first ceramic setter plate (namely, A type) in the technical scheme, which comprises the following steps:

a) preparing ceramic slurry A and sacrificial slurry XS;

the sacrificial slurry XS comprises the following components:

b) tape casting:

c) And (3) curing:

the material belt is

Placing in water for curing to obtain wet blank

d) Wet blank treatment:

for the wet blank

Curing to obtain a green body

e) And (3) sintering:

to the green body

Sintering to obtain a ceramic setter plate A;

With respect to step a): ceramic slurry a and sacrificial slurry XS were prepared.

The raw material composition and the preparation method of the ceramic slurry a are the same as those in the foregoing technical solutions, and are not described in detail here.

The sacrificial slurry XS comprises the following components: sacrificial materials, binders, dispersants, and solvents.

Wherein:

the sacrificial material is a powder material which can be discharged through sintering and is insoluble in the solvent, and the powder material is organic powder and/or inorganic powder. The sacrificial material is preferably one or more of graphite, starch and wood chips. The content of the sacrificial material is 30 wt% -60 wt%.

The binder is preferably one or more of PESF (i.e., polyphenylene ether sulfone), PES (i.e., polyether sulfone), and PVB (i.e., polyvinyl butyral). In the invention, the content of the binder is 3-10 wt%.

The dispersant is preferably PVP (i.e. polyvinylpyrrolidone) and/or DSP (i.e. modified fish oil). In the invention, the content of the dispersant is 1 wt% -5 wt%.

The solvent is selected from NMP (i.e., N-methylpyrrolidone), DMAc (i.e., dimethyl ethyl phthalein amine)

) And DMSO (i.e., dimethyl sulfoxide), more preferably NMP (i.e., N-methylpyrrolidone). In the invention, the content of the solvent is 30-60 wt%.

The invention is not particularly limited in the manner of making the above components into slurry, and it is sufficient to make the slurry according to the conventional pulping manner in the art, specifically, the sacrificial material, the binder, the dispersant and the solvent are mixed to obtain the sacrificial slurry XS. In the present invention, the mixing is preferably performed by ball milling. The rotation speed of the ball milling is preferably 25-50 rpm. The ball milling time is preferably 10-20 h. And (4) carrying out mixing treatment to obtain uniform sacrificial slurry XS.

With respect to step b): and (4) tape casting.

In the double-layer casting, the height of a front cutter and the height of a rear cutter of a casting cutter are respectively adjusted, and then slurry is added for casting forming. In the present invention, it is preferable that the ceramic slurry A is fed between the front and rear and the rear blade, and the sacrificial slurry XS is fed behind the rear blade to obtain the ceramic slurry layer AComposite material belt with upper sacrificial sizing layer XS and lower sacrificial sizing layer XS

The height between the front cutter and the rear cutter corresponds to the thickness of the ceramic slurry layer A, and the height of the rear cutter corresponds to the thickness of the sacrificial slurry layer XS.

In the invention, the thickness of the ceramic A layer is preferably 2-3 mm, and the thickness of the XS layer (namely the sacrificial layer) is preferably 0.1-0.5 mm.

With respect to step c): and (5) curing.

The material belt is

Placing in water for curing to obtain wet blank

The invention has no special limit on the using amount of the water and can completely submerge the material belt

And (4) finishing. The time for curing in water is preferably 5-20 h. The principle of forming the gradient straight-hole structure by solidification in water is consistent with the foregoing description, and is not repeated herein. Wherein, the material belt

The invention controls the compositions of the slurry to be the ceramic slurry A and the sacrificial slurry XS shown in the specification, and simultaneously controls the curing process and parameters as follows: the material belt is arranged along the thickness direction of the plate body

Vertically and stably put into water until the material belt is put into

And completely immersing the sacrificial layer XS in water, wherein the sacrificial layer XS is arranged below the slurry A, the slurry A is arranged above the slurry A (namely the depth of the sacrificial layer XS in the water is deeper), the temperature of the water is 5-30 ℃, and the curing time is 5-20 h. Preferably, the temperature of the water is 15 ℃.In some embodiments, the volume ratio of water to all solvent contained in the tape is 80: 1, but is not so limited.

After the solidification treatment, the upper part of the plate body (corresponding to the layer A of the ceramic slurry) forms a straight hole structure, and the aperture changes in a gradient manner from one end of the straight hole to the other end; the lower part of the plate body corresponds to the sacrificial layer XS, and the internal structure of the sacrificial layer is porous and spongy. Curing and forming to obtain a wet blank

In the ceramic layer A, one surface far away from the sacrificial slurry XS layer corresponds to the thin end of the gradient straight hole, and the surface in contact with the sacrificial slurry XS layer corresponds to the thick end of the gradient straight hole.

With respect to step d): and (5) wet blank treatment.

For the wet blank

Drying and maintaining to obtain green body

In the invention, before airing and maintaining, the target product is preferably cut into a certain shape and size, and then airing and maintaining are carried out. In the present invention, the conditions for drying and maintaining are preferably as follows: the temperature is 10-35 ℃, the relative humidity is 20-80%, and the time is 10-40 h. By the above treatment, a green compact is obtained

With respect to step e): and (5) sintering.

To the green body

Sintering to obtain the ceramic setter plate A. In the present invention, the sintering preferably includes: the first heating, the glue discharging and the second heating. The first temperature raising condition is preferably: the heating rate is preferably 1-5 ℃/min, the target temperature is preferably 600-800 ℃, and the heat preservation time is preferably 1-5 h. After the first temperature raising treatment, the process is carried outAnd (5) removing the glue, and then carrying out second temperature rise treatment. The second temperature rise condition is preferably: the heating rate is preferably 3-10 ℃/min, the target temperature is preferably 1300-1500 ℃, and the heat preservation time is preferably 2-10 h. After the sintering treatment, the sacrificial layer (i.e., XS layer) is sintered away, and the ceramic setter plate A is obtained.

In the ceramic setter plate A, the plate body comprises a gradient straight hole layer which corresponds to the structure of the first ceramic setter plate in the technical scheme, as shown in fig. 1-2, in which gradient straight holes penetrate through both surfaces, but since the gradient straight holes have smaller hole diameters, therefore, microscopically, the gradient straight holes penetrate through the two surfaces, but macroscopically, the holes cannot be seen on the upper surface and the lower surface of the plate body by naked eyes, but still as a compact plate, in the second preparation method, the sacrificial layer is introduced first and then sintered, so that a rough surface is formed on the sacrificial layer removing surface (i.e. the surface where the thick end of the gradient straight hole in the ceramic setter plate a is located), that is, the surface where the straight-hole thick end is located is a relatively rough honeycomb surface in appearance (see fig. 8), and the surface where the straight-hole thin end is located is a smooth surface in appearance (see fig. 9).

The invention also provides a second ceramic load bearing plate (namely, the second ceramic load bearing plate) in the technical scheme

Form (b) comprising the steps of:

a) preparing ceramic slurry A and ceramic slurry B;

the ceramic slurry B comprises the following components:

the ceramic raw material is prepared from a ceramic raw material,

b) tape casting:

c) And (3) curing:

the material belt is

Placing in water for curing to obtain wet blank

d) Wet blank treatment:

for the wet blank

Drying and maintaining to obtain green body

e) And (3) sintering:

to the green body

Sintering to obtain the ceramic setter plate

The obtained ceramic setter plate

With respect to step a): ceramic slurry a and ceramic slurry B were prepared.

In the invention, the ceramic slurry B comprises the following components: ceramic raw materials, a binder, a dispersant, a pore-forming agent and a solvent.

Wherein:

the ceramic raw material is ceramic powder and/or ceramic fiber. Wherein, the ceramic material is preferably one or more of alumina, zirconia, silica, titania, magnesia, kaolin, calcium carbonate, silicon carbide, talc, feldspar, cordierite, diatomite, mullite and boehmite.

The binder is preferably one or more of PESF (i.e., polyphenylene ether sulfone), PES (i.e., polyether sulfone), and PVB (i.e., polyvinyl butyral). In the present invention, the binder is preferably present in an amount of 3 to 10 wt% based on the mass of the ceramic raw material.

The dispersant is preferably PVP (i.e. polyvinylpyrrolidone) and/or DSP (i.e. modified fish oil). In the present invention, the dispersant preferably accounts for 0.5 wt% to 5 wt% of the mass of the ceramic raw material.

The pore-forming agent is preferably one or more of starch, graphite and wood chips. In the present invention, it is preferable that the volume of the pore-forming agent is 5% to 30% of the volume of the ceramic raw material.

) And DMSO (i.e., dimethyl sulfoxide), more preferably NMP (i.e., N-methylpyrrolidone). In the present invention, the solvent preferably accounts for 30 wt% to 60 wt% of the mass of the ceramic raw material.

The invention has no special limitation on the mode of preparing the components into the slurry, and the ceramic slurry B can be obtained by mixing the ceramic raw material, the binder, the dispersant, the pore-forming agent and the solvent according to the conventional pulping mode in the field. Preferably, the ceramic raw material, the dispersant, the pore-forming agent and the solvent are uniformly mixed, and then the binder is added and continuously and uniformly mixed. In the present invention, the mixing is preferably performed by ball milling. The rotation speed of the ball milling is preferably 25-50 rpm. The ball milling time is preferably 14-30 h, wherein the ball milling time is preferably 4-10 h before the binder is added, and the ball milling time is preferably 10-20 h after the binder is added. And (3) carrying out mixing treatment to obtain uniform ceramic slurry B.

According to the component introduction, the component types and specific selection ranges of the components of the ceramic slurry A and the ceramic slurry B are the same, and when the ceramic slurry A and the ceramic slurry B are simultaneously adopted, the components of the same type are independently selected from the corresponding selection ranges, namely the ceramic slurry A and the ceramic slurry B can be the same or different. When the ceramic slurry A and the ceramic slurry B are the same (namely, only one slurry is adopted), single-layer tape casting can be carried out to prepare the material belt, and a structure comprising a gradient straight hole layer and a capillary hole layer can be formed in subsequent solidification.

With respect to step b): and (4) tape casting.

In the double-layer casting, the height of a front cutter and the height of a rear cutter of a casting cutter are respectively adjusted, and then slurry is added for casting forming. In the present invention, it is preferable that the ceramic slurry A is fed between the front and rear blades and the rear blade, and the ceramic slurry B is fed behind the rear blade, thereby obtaining a composite tape in which the ceramic slurry layer A is on the upper side and the ceramic slurry layer B is on the lower side

Wherein, the height between the front cutter and the rear cutter corresponds to the thickness of the ceramic A layer, and the height of the rear cutter corresponds to the thickness of the ceramic B layer.

In the invention, the thickness of the ceramic layer A is preferably 2-4 mm, and the thickness of the ceramic layer B is preferably 0.1-0.5 mm.

With respect to step c): and (5) curing.

The material belt is

Is put into water forCuring to obtain a wet blank

And (4) finishing. The time for curing in water is preferably 10-20 h. The principle of forming the gradient straight hole layer and the capillary hole layer by curing in water is consistent with the principle described above, in the process of placing the material belt in water for curing, the phase-inversion slurry is contacted with water, the water enters the slurry to generate a viscosity finger-entering phenomenon, and the entry of the water simultaneously causes the thermodynamic equilibrium of the binder and the solvent in the slurry to be greatly broken, so that phase separation is generated; the finger-like pore layer is formed when the viscosity dominates, and the capillary structure dominates when phase separation dominates. Specifically, in the phase inversion process, water is exchanged with the solvent in the slurry, the binder is gradually separated out from the solvent to drive the ceramic powder in the slurry to be rearranged, meanwhile, the slurry is gradually gelatinized, the gelation time is short, the gel front advancing speed is high, the concentration of the polymer (namely the binder in the slurry) is low, the membrane tends to form a finger-shaped macroporous structure, and in the later curing period, the gelation time is long, the gel front advancing speed is low, the polymer concentration is high, and the membrane tends to form a spongy structure with only capillary pores.

For the material belt

The invention controls the compositions of the slurry to be the ceramic slurry A and the ceramic slurry B shown in the specification, and simultaneously controls the curing process and parameters as follows: the material belt is arranged along the thickness direction of the plate body

Vertically and stably put into water until the material belt is put into

Completely submerged in water with slurry B layer below and slurry a layer above (i.e., deeper depth of slurry B layer in water), the temperature of the waterThe curing time is 5-20 h at 5-30 ℃. Preferably, the temperature of the water is 15 ℃. In some embodiments, the volume ratio of water to all solvent contained in the tape is 80: 1, but is not so limited. After the solidification treatment, the upper part of the plate body (corresponding to the ceramic layer A) forms a straight hole structure, and the aperture changes in a gradient manner from one end of the straight hole to the other end; the lower part of the plate body (i.e. corresponding to the ceramic layer B) forms a capillary structure. Curing and forming to obtain a wet blank

In the ceramic layer A, one surface far away from the ceramic layer B corresponds to the thin end of the gradient straight hole, and the surface in contact with the ceramic layer B corresponds to the thick end of the gradient straight hole.

If a plurality of material belts are simultaneously cured (namely, a batch of material belts are simultaneously cured) in the same container, when a plurality of material belts are required to be stacked, the distance between two adjacent material belts is required to be controlled to be not less than 20 mm; specifically, multiple layers of partition plates can be arranged in the container, the material belts are arranged on the partition plates on different layers, and the distance between the different material belts is controlled through the installation height of the partition plates.

With respect to step d): and (5) wet blank treatment.

For the wet blank

Drying and maintaining to obtain green body

With respect to step e): and (5) sintering.

To the green body

Sintering to obtain the ceramic setter plate

In the present invention, the sintering preferably includes: the first heating, the glue discharging and the second heating. The first temperature raising condition is preferably: the heating rate is preferably 1-3 ℃/min, the target temperature is preferably 600-800 ℃, and the heat preservation time is preferably 1-5 h. After the first temperature rise treatment, the glue is discharged, and then the second temperature rise treatment is carried out. The second temperature rise condition is preferably: the heating rate is preferably 3-10 ℃/min, the target temperature is preferably 1300-1500 ℃, and the heat preservation time is preferably 2-10 h. After the sintering treatment, the ceramic setter plate is obtained

Namely a composite plate body with a ceramic layer A at the upper part and a ceramic layer B at the lower part

The ceramic load bearing plate

In, the plate body includes straight hole layer of gradient and capillary pore layer, corresponds the structure of the second kind of pottery bearingburning board among the above-mentioned technical scheme.

The invention also provides a third ceramic load bearing plate (namely, a third ceramic load bearing plate) in the technical scheme

Form (b) comprising the steps of:

a) preparation of Wet Green bodies A and A, respectively

b) Green body treatment:

mixing the wet blank A and the wet blank

Stacking and pressing to obtain a composite green body

Wherein, during the stacking process, the thin end surface in the gradient straight hole layer in the wet blank A and the wet blank

The thin end surfaces in the middle gradient straight hole layer are contacted;

c) and (3) sintering:

to the composite green body

Sintering to obtain the ceramic setter plate

With respect to step a):

in the present invention, a wet green A and a wet green are prepared

The preparation method is the same as that in the above technical scheme, and is not described in detail herein.

With respect to step b):

before stacking, preferably, the two wet blanks are cut, dried and maintained. Wherein, the conditions of the drying and maintenance are the same as those in the above technical scheme, and are not repeated herein. After the above treatment, the two wet blanks are stacked.

During the stacking process, the thin end surface in the gradient straight hole layer in the wet blank A and the wet blank

Thin end surfaces in a medium gradient straight bore layerContacting; in practice, two wet blanks are stacked in contact on the upward facing surface during casting (i.e., the side of the wet blank a in contact with the doctor blade front and the side of the wet blank a in contact with the doctor blade rear).

And pressing after the overlapping. In the invention, the pressing temperature is preferably 50-80 ℃. The pressure of the pressing is preferably 500-1000 Psi. The pressure maintaining time of the pressing is preferably 0.5-5 min. And pressing to obtain the composite green body.

With respect to step c):

I.e. the first plate (ceramic A) is arranged on the upper part and the second plate (ceramic A)

) Composite plate body under

Wherein, one surface of the first plate body (ceramic A) corresponding to the thin end of the gradient straight hole is corresponding to the second plate body (ceramic

) The surfaces corresponding to the thin ends of the middle gradient straight holes are contacted.

The ceramic load bearing plate

Comprises a first plate body and a second plate body corresponding to the first plate body in the technical schemeThree ceramic setter plate structures.

The invention also provides a preparation method of other ceramic setter plates in the technical scheme, which is carried out on the basis of the preparation methods of the first ceramic setter plate to the third ceramic setter plate, and the preparation process of the ceramic setter plates is referred to, and the individual steps are correspondingly adjusted according to the structural composition of the target ceramic setter plate.

For a further understanding of the invention, reference will now be made to the preferred embodiments of the invention by way of example, and it is to be understood that the description is intended to further illustrate features and advantages of the invention, and not to limit the scope of the claims. In the following examples, the particle size of the ceramic powder is 1 to 100. mu.m.

Example 1: preparing a ceramic setter plate A (as shown in figure 1-2)

S1, preparing ceramic slurry A and sacrificial layer slurry XS:

(1) ceramic slurry A raw material:

ceramic powder: 80 wt% of alumina fine powder, 10 wt% of silica fine powder, 5 wt% of kaolin fine powder and 5 wt% of titanium oxide fine powder;

adhesive: polyvinyl butyral PVB accounting for 7.5 wt% of the ceramic powder;

dispersing agent: polyvinylpyrrolidone accounting for 1.5 wt% of the ceramic powder;

pore-forming agent: graphite with a median particle size D50 of 35 μm, the volume of which accounts for 15% of the volume of the ceramic powder;

solvent: n-methyl-2-pyrrolidone NMP accounts for 48 wt% of the total mass of the ceramic powder and the pore-forming agent.

Preparation of ceramic slurry A: mixing and ball-milling the ceramic powder, the pore-forming agent, the dispersing agent and the solvent for 5 hours, adding the binder, and continuing ball-milling for 15 hours to obtain ceramic slurry A.

(2) Sacrificial layer slurry XS raw material:

preparation of sacrificial slurry XS: and mixing the sacrificial material, the dispersing agent, the binder and the solvent, and performing ball milling for 20 hours to obtain sacrificial slurry XS.

S2, casting:

double-layer casting: adjusting the height of a front cutter of a casting cutter to 2.5mm, adjusting the height of a rear cutter to 0.3mm, adding sacrificial slurry XS behind the rear cutter, adding ceramic slurry A between the front cutter and the rear cutter, and casting to obtain the material belt

S3, curing:

feeding belt

Placing in water for curing for 15h, specifically: the material belt is arranged along the thickness direction of the plate body

Vertically and stably put into water until the material belt is put into

Completely immersed in water with the sacrificial layer XS layer below and the slurry A layer above (i.e., deeper depth of the sacrificial layer XS in water), the temperature of the water being 15 deg.C, the water and the tape

The volume ratio of all solvents contained in the mixture is 80: 1, and the mixture is solidified for 15 hours to obtain a wet blank

S4, green body treatment:

the wet blank is processed

Cutting into a certain shape and size,then airing the green body for 30 hours in an environment with the temperature of 30 ℃ and the relative humidity of 60 percent to obtain a green body

S5, sintering:

mixing the green body

Heating to 800 ℃ at the speed of 1 ℃/min, preserving heat for 2h, then removing glue, heating to 1450 ℃ at the speed of 3 ℃/min, preserving heat for 5h, wherein the sacrificial layer XS is burnt off, and the ceramic setter plate A is obtained. The structure of the resulting product is shown in fig. 1-2.

Example 2: preparing ceramic load bearing board

(as shown in FIGS. 3-4)

S1, preparing ceramic slurry A and ceramic slurry B;

(1) ceramic slurry A raw material:

ceramic powder: 60 wt% of mullite fine powder, 20 wt% of white corundum powder, 15 wt% of boehmite fine powder, 3.5 wt% of kaolin fine powder and 1.5 wt% of calcium carbonate powder;

adhesive: polyvinyl butyral PVB accounting for 7.5 wt% of the ceramic powder;

dispersing agent: polyvinylpyrrolidone accounting for 1.7 wt% of the mass of the ceramic powder;

pore-forming agent: graphite with a median particle size D50 of 35 μm, the volume of which accounts for 10% of the volume of the ceramic powder;

solvent: n-methyl-2-pyrrolidone NMP accounts for 40 wt% of the total mass of the ceramic powder and the pore-forming agent.

(2) Ceramic slurry B raw materials:

adhesive: polyvinyl butyral PVB accounting for 7.5 wt% of the ceramic powder;

Preparation of ceramic slurry B: mixing and ball-milling the ceramic powder, the pore-forming agent, the dispersing agent and the solvent for 5 hours, adding the binder, and continuing ball-milling for 15 hours to obtain ceramic slurry B.

S2, casting:

double-layer casting: adjusting the height of a front cutter of a casting cutter to 3mm, adjusting the height of a rear cutter to 0.3mm, adding ceramic slurry B behind the rear cutter, adding ceramic slurry A between the front cutter and the rear cutter, and casting to obtain the material belt

S3, curing:

feeding belt

Placing in water for curing for 10 hours, specifically: the material belt is arranged along the thickness direction of the plate body

Vertically and stably put into water until the material belt is put into

Completely immersed in water, wherein slurry B layer is below and slurry A layer is above (i.e. the depth of slurry B layer in water is deeper), the temperature of water is 15 ℃, and water and the material belt

The volume ratio of all solvents contained in the mixture is 80: 1, and the mixture is solidified for 10 hours to obtain a wet blank

S4, green body treatment:

the wet blank is processed

Cutting into certain shape and size, air drying at 20 deg.C and 60% relative humidity for 30 hr to obtain green body

S5, sintering:

mixing the green body

Heating to 800 deg.C at a rate of 1 deg.C/min, maintaining for 2 hr, removing glue, heating to 1450 deg.C at a rate of 3 deg.C/min, and maintaining for 5 hr to obtain ceramic setter plate

The structure of the resulting product is shown in fig. 3-4.

Example 3: preparation of ceramic setter plate A-A

S1, preparing ceramic slurry A and sacrificial layer slurry XS:

(1) ceramic slurry A raw material:

adhesive: polyvinyl butyral PVB accounting for 7.5 wt% of the ceramic powder;

(2) Sacrificial layer slurry XS raw material:

S2, casting:

(1) single-layer casting: the height of the casting knife is adjusted to 2.0mm, and a ceramic slurry material belt A with the thickness of about 2.0mm is cast.

(2) Double-layer casting: adjusting the height of a front cutter of a casting cutter to 2.5mm, adjusting the height of a rear cutter to 0.3mm, adding sacrificial slurry XS behind the rear cutter, adding ceramic slurry A between the front cutter and the rear cutter, and casting to obtain the material belt

S3, curing:

respectively arranging the material belt A and the material belt

And (3) placing the material strip A in water for curing for 15h, wherein the curing of the material strip A is as follows: vertically putting the material belt A into water along the thickness direction of the plate body and stably putting the material belt A into the water until the material belt A is completely immersed into the water, wherein the temperature of the water is 15 ℃, the volume ratio of the water to the solvent contained in the material belt A is 80: 1, and curing for 15 h. Material belt

The curing of (a) is as follows: taking another container filled with water, and placing the material belt along the thickness direction of the plate body

Vertically and stably put into water until the material belt is put into

Completely submerged in water with the sacrificial layer XS layer below and the slurry A layer above (i.e., deeper depth of the sacrificial layer XS layer in water), with waterAt a temperature of 15 ℃, water and the material belt

The volume ratio of all solvents contained in the resin is 80: 1, and the curing time is 15 hours. Respectively obtaining a wet blank A and a wet blank through the treatment

S4, green body treatment:

mixing the wet blank A and the wet blank

Cutting into certain shape and size, air drying at 30 deg.C and 60% relative humidity for 30 hr to obtain green body A and green body

Thereafter, green body A and green body

Stacking, specifically stacking the upward surfaces of the two blanks during casting, and pressing at 65 ℃ under 700Psi and 3min of pressure maintaining to obtain a composite green blank with a thickness of about 3.3mm

S5, sintering:

compounding the green body

Heating to 800 ℃ at the speed of 1 ℃/min, preserving heat for 2h, then removing glue, heating to 1450 ℃ at the speed of 3 ℃/min, preserving heat for 5h, wherein the sacrificial layer XS is burnt off, and the ceramic setter plate A-A is obtained. Wherein, the one side that the thin end of straight hole corresponds in the gradient straight hole layer in two plate bodies A contacts each other.

Example 4: preparing ceramic load bearing board

(as shown in FIGS. 5-6)

S1, preparing ceramic slurry A, ceramic slurry B and sacrificial slurry XS;

(1) ceramic slurry A raw material:

adhesive: polyvinyl butyral PVB accounting for 7.5 wt% of the ceramic powder;

(2) Ceramic slurry B raw materials:

adhesive: polyvinyl butyral PVB accounting for 7 wt% of the ceramic powder;

(3) Sacrificial slurry XS feedstock:

S2, casting:

(1) double-layer casting of ceramic slurry: adjusting the height of a front cutter of a casting cutter to 3mm, adjusting the height of a rear cutter to 0.3mm, adding ceramic slurry B behind the rear cutter, adding ceramic slurry A between the front cutter and the rear cutter, and casting to obtain the material belt

(2) Double-layer tape casting of ceramic slurry and sacrificial slurry: adjusting the height of a front cutter of a casting cutter to 3mm, adjusting the height of a rear cutter to 0.3mm, adding sacrificial slurry XS behind the rear cutter, adding ceramic slurry A between the front cutter and the rear cutter, and casting to obtain the material belt

S3, curing:

respectively put the material belt

Material mixing belt

Curing in water for 10 hr to obtain a material belt

The curing of (a) is as follows: the material belt is arranged along the thickness direction of the plate body

Vertically and stably put into water until the material belt is put into

The volume ratio of all solvents contained in the resin is 80: 1, and the curing time is 10 hours. Material belt

Vertically and stably put into water until the material belt is put into

Completely immersed in water at 15 deg.C with the sacrificial layer XS layer below and the slurry A layer above (i.e., deeper depth of the sacrificial layer XS layer in water), and water and the tape

The volume ratio of all solvents contained in the resin is 80: 1, and the curing time is 10 hours. Respectively obtaining wet blanks by the treatment

And wet green

S4, green body treatment:

the wet blank is processed

And wet green

Cutting into certain shape and size, air drying at 20 deg.C and 60% relative humidity for 30 hr to obtain green bodies

And green compact

Thereafter, the green body is pressed

And green compact

Stacking the surfaces of the A layers of the two green bodies, and pressing at 65 deg.C under 700Psi for 3min to obtain a composite green body with a thickness of about 4.5mm

S5, sintering:

compounding the green body

Heating to 800 deg.C at a rate of 1 deg.C/min, maintaining for 2 hr, removing glue, heating to 1450 deg.C at a rate of 3 deg.C/min, and maintaining for 5 hr, wherein the sacrificial layer XS is burned off to obtain the ceramic setter plate

Wherein, the one side that the thin end of the straight hole in the gradient straight hole layer corresponds in two plate bodies contacts each other. The structure of the resulting product is shown in fig. 5-6.

Example 5:

(1) characterization of

The microstructure test of the cross section of the ceramic setter a-a obtained in example 3 was carried out, and the result is shown in fig. 7, and fig. 7 is an optical microscope photograph of the cross section of the ceramic setter obtained in example 3. It can be seen that a plurality of gradient straight hole structures appear inside the setter plate.

Observing the appearance of the upper and lower surfaces of the ceramic setter plate obtained in example 3, and as a result, as shown in fig. 8-9, fig. 8 is a schematic surface diagram of the honeycomb surface of the ceramic setter plate obtained in example 3, the honeycomb surface corresponds to the surface where the sacrificial layer XS is burned off, and a rough honeycomb structure is formed on the surface of the plate body due to the sintering off of the sacrificial layer XS; FIG. 9 is a schematic view of the smooth surface of the ceramic setter plate obtained in example 3.

(2) Performance testing

The ceramic setter plates obtained in examples 1 to 4 were subjected to performance tests, and the results are shown in Table 1.

TABLE 1 Properties of the ceramic setter plates obtained in examples 1 to 4

As can be seen from the test results in Table 1, the ceramic setter plates provided by the present invention have porosity of more than 55% and air permeability of 8500m³/m²H.bar or more, the three-point bending strength of 9.5MPa or more, higher porosity, good air permeability and mechanical strength.

The foregoing examples are provided to facilitate an understanding of the principles of the invention and their core concepts, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention. The scope of the invention is defined by the claims and may include other embodiments that occur to those skilled in the art. Such other embodiments are intended to be within the scope of the claims if they have structural elements that approximate the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claims

1. A ceramic setter plate is characterized in that a plate body comprises a gradient straight hole layer;

2. The ceramic setter plate of claim 1, wherein the dimensions of each of the gradient straight holes are independently selected from the group consisting of: the aperture of the thin end is 0.1-10 μm, the aperture of the thick end is 50-500 μm, and the length of the pore channel is 0.1-5 mm.

3. The ceramic setter plate of claim 1 or 2, wherein the plate body comprises a gradient straight hole layer and a capillary hole layer;

the capillary hole layer comprises a plurality of capillary holes.

4. The ceramic setter plate of claim 3, wherein the pore size of the plurality of capillaries in the capillary layer is independently selected from the group consisting of: 0.1 to 80 μm.

5. The ceramic setter plate of claim 1, wherein the plate body comprises a first plate body and a second plate body that are laminated and compounded;

the first plate body comprises a gradient straight hole layer;

6. A method for preparing the ceramic setter plate of any one of claims 1 to 5, comprising:

a) preparing ceramic slurry A and sacrificial slurry XS;

the ceramic slurry A comprises the following components:

the ceramic raw material is prepared from a ceramic raw material,

the sacrificial slurry XS comprises the following components:

b) tape casting:

c) And (3) curing:

the material belt is

Placing in water for curing to obtain wet blank

d) Wet blank treatment:

for the wet blank

Drying and maintaining to obtain green body

e) And (3) sintering:

to the green body

Sintering to obtain a ceramic setter plate A;

7. A method for preparing the ceramic setter plate of any one of claims 1 to 5, comprising:

a) preparing ceramic slurry A and ceramic slurry B;

the ceramic slurry B comprises the following components:

the ceramic raw material is prepared from a ceramic raw material,

b) tape casting:

c) And (3) curing:

the material belt is

Placing in water for curing to obtain wet blank

d) Wet blank treatment:

for the wet blank

Drying and maintaining to obtain green body

e) And (3) sintering:

to the green body

Sintering to obtain the ceramic setter plate

The obtained ceramic setter plate

8. The production method according to claim 6 or 7,

in the ceramic slurry a:

the ceramic raw material is ceramic powder and/or ceramic fiber;

the binder is selected from one or more of PESF, PES and PVB;

the dispersing agent is PVP and/or DSP;

the pore-forming agent is one or more of starch, graphite and wood chips;

the solvent is one or more selected from NMP, DMAc and DMSO.

9. The production method according to claim 7,

in the ceramic slurry B:

the ceramic raw material is ceramic powder and/or ceramic fiber;

the binder is selected from one or more of PESF, PES and PVB;

the dispersing agent is PVP and/or DSP;

the pore-forming agent is one or more of starch, graphite and wood chips;

the solvent is one or more selected from NMP, DMAc and DMSO.

10. The production method according to claim 6,

in the sacrificial slurry XS:

the binder is selected from one or more of PESF, PES and PVB;

the dispersing agent is PVP and/or DSP;

the solvent is one or more selected from NMP, DMAc and DMSO.