CN115500563A

CN115500563A - Porous ceramic matrix, ceramic atomizing core and preparation method thereof

Info

Publication number: CN115500563A
Application number: CN202211267269.7A
Authority: CN
Inventors: 李俊辉; 赵贯云; 赵波洋; 聂革
Original assignee: Shenzhen Woody Vapes Technology Co Ltd
Current assignee: Shenzhen Woody Vapes Technology Co Ltd
Priority date: 2022-10-17
Filing date: 2022-10-17
Publication date: 2022-12-23

Abstract

The invention relates to the field of electronic atomizers, and provides a porous ceramic matrix, a ceramic atomizing core and a preparation method thereof. The porous ceramic base body is of a layered structure, the grain sizes of ceramic raw materials of all layers of the porous ceramic base body are sequentially increased along the direction from a first surface to a second surface, and the first surface is opposite to the second surface. The ceramic atomizing core comprises the porous ceramic matrix and a heating body, wherein the heating body is attached to the first surface of the porous ceramic matrix. The preparation method comprises preparing the porous ceramic matrix; and sputtering the metal material to the first surface of the porous ceramic matrix uniformly by a vacuum sputtering coating process to form the heating element. According to the invention, on one hand, the porous ceramic matrix with the layered structure and different particle sizes of each layer is adopted, on the other hand, the metal material is uniformly sputtered to the first surface of the porous ceramic matrix by adopting a vacuum sputtering coating process to form the heating element, and the two aspects are combined, so that the bonding force between the porous ceramic matrix and the heating element is improved.

Description

Porous ceramic matrix, ceramic atomizing core and preparation method thereof

Technical Field

The invention relates to the field of electronic atomizers, in particular to a porous ceramic matrix, a ceramic atomizing core and a preparation method thereof.

Background

The ceramic atomization core is an important part of the electronic atomizer, and during atomization, atomized liquid is conducted by virtue of the capillary action of the porous ceramic matrix and is atomized by heat after passing through a heating body on the porous ceramic matrix.

The existing porous ceramic matrix is mainly prepared by taking raw materials such as diatomite, quartz sand, alumina powder and the like as main bodies, adding a certain amount of binder and pore-forming agent for molding, degreasing and sintering, wherein the particle diameters of the raw materials are inconsistent, and the obtained pore diameter distribution uniformity is poor. The heating body of the existing ceramic atomizing core is generally combined with the porous ceramic matrix by adopting a steel mesh embedding mode or a thick film printing mode. These have resulted in the heating element of pottery atomizing core and the bonding force poor of porous ceramic base member, lead to heating element and porous ceramic base member to break away from easily and lead to pottery atomizing core to paste the core in the use, have influenced product life greatly, influence experience.

Disclosure of Invention

The invention aims to provide a porous ceramic matrix, a ceramic atomizing core and a preparation method thereof, so as to improve the binding force between the porous ceramic matrix and a heating element.

The porous ceramic base body provided by the invention is of a layered structure, and the porous ceramic base body is provided with a first surface and a second surface, wherein the second surface is opposite to the first surface, and the grain diameters of ceramic raw materials of all layers of the porous ceramic base body are sequentially increased along the direction from the first surface to the second surface.

Preferably, the pore diameters of the layers of the porous ceramic base body increase in order along the direction from the first face to the second face.

Preferably, the grain size of the ceramic raw material of the layer on which the first face is located is 10 micrometers, and the grain size of the ceramic raw material of the layer on which the second face is located is greater than 80 micrometers.

The invention provides a ceramic atomizing core, which comprises: the porous ceramic substrate described above; and a heating element attached to the first surface of the porous ceramic base.

Preferably, the heating element is a metal layer, and the metal layer is plated on the first surface of the porous ceramic matrix.

The preparation method of the ceramic atomizing core provided by the invention comprises the following steps: preparing the porous ceramic matrix; and sputtering the metal material to the first surface of the porous ceramic matrix uniformly by a vacuum sputtering coating process to form the heating element.

In some embodiments, the step of preparing the porous ceramic matrix comprises: screening to obtain ceramic raw materials with different gradient particle sizes; respectively mixing ceramic raw materials with different particle sizes with a sintering aid to form an aid-containing ceramic raw material; according to the grain size of the ceramic raw material, the ceramic raw materials with various grain sizes and containing the auxiliary agent are configured in a layered mode, and a layered blank is formed through compression molding; and (3) removing the glue from the layered blank, and sintering to obtain the porous ceramic matrix.

In some embodiments, the step of preparing the porous ceramic matrix further comprises: before the ceramic raw material containing the auxiliary agent is formed, the ceramic raw material is cleaned, and then the ceramic raw material is roasted at 400-800 ℃.

In some embodiments, the ceramic raw material is selected from diatomaceous earth, quartz sand, and alumina, the ceramic raw material obtained by screening has gradient particle sizes including 10 microns, 30 microns, 50 microns, 80 microns, and 100 microns, and the sintering aid includes a plasticizer, a binder, a dispersant, a pore-forming agent, and a sintering aid.

In some embodiments, the temperature rising system of the binder removal is as follows: raising the temperature from room temperature to 600 ℃, wherein the raising rate from room temperature to 200 ℃, from 200 ℃ to 400 ℃, and from 500 ℃ to 600 ℃ is less than 1 ℃/min; the temperature rising system of sintering is as follows: heating the mixture from room temperature to 900 ℃ at the speed of 2-5 ℃/min, and keeping the temperature for 30min; heating from 900 ℃ to the sintering temperature at the speed of 2-10 ℃/min, and preserving the heat for 2h.

Compared with the prior art, the invention has at least the following beneficial effects:

the porous ceramic matrix is of a layered structure, the porous ceramic matrix is provided with a first surface and a second surface which are opposite, and the grain sizes of the ceramic raw materials of all layers of the porous ceramic matrix are sequentially increased along the direction from the first surface to the second surface, so that the porous ceramic matrix can meet the requirements of an atomizing core on the pore size and the porosity, and the first surface has higher flatness, so that after a heating element is attached to the first surface to form the ceramic atomizing core, the bonding force between the porous ceramic matrix and the heating element can be improved.

According to the preparation method of the ceramic atomizing core, on one hand, the porous ceramic matrix with the layered structure and different particle sizes of each layer is adopted, on the other hand, the heating body is formed by uniformly sputtering the metal material to the first surface of the porous ceramic matrix by adopting a vacuum sputtering coating process, and the two aspects are combined, so that the bonding force between the porous ceramic matrix and the heating body is better.

Drawings

FIG. 1 is a schematic structural view of a porous ceramic matrix according to some embodiments;

FIG. 2 is a schematic structural view of a ceramic atomizing core according to some embodiments;

fig. 3 illustrates a process for preparing a porous ceramic matrix according to some embodiments.

Detailed Description

The invention is further illustrated with reference to the following figures and examples.

Referring to fig. 1, the porous ceramic substrate 10 of some embodiments has a layered structure, the porous ceramic substrate 10 has a first surface 1 and a second surface 7, the second surface 7 is opposite to the first surface 1, the layered structure of the porous ceramic substrate 10 in this embodiment specifically includes a first layer 2, a second layer 3, a third layer 4, a fourth layer 5, a fifth layer 6, and five layers, and the particle sizes of the ceramic raw materials of the layers of the porous ceramic substrate 10 are sequentially increased along a direction from the first surface 1 to the second surface 7, that is, the particle size of the ceramic raw material of the first layer 2 is the smallest, and the particle size of the ceramic raw material of the fifth layer 6 is the largest.

In the field of electronic atomizers, the porous ceramic matrix is used for loading a heating element, and is also used for buffering atomized liquid and conducting the atomized liquid to the heating element. In the porous ceramic base 10, the particle size of the ceramic material of the first layer 2 is the smallest, so that the first surface 1 has high flatness and is suitable for plating a heating element by a vacuum sputtering coating process. Compared with the first layer 2, the grain sizes of the ceramic raw materials of the second layer 3 to the fifth layer 6 are larger, and the matching of the grain sizes enables the pore size and the porosity of the porous ceramic matrix 10 to meet the requirements of the ceramic atomizing core on the pore size and the porosity. Generally, the porosity of the porous ceramic matrix of the ceramic atomizing core can be 50-80%, and the pore diameter can be 5-50 μm.

In one embodiment, the grain size of the ceramic raw material of the first layer 2, the second layer 3, the third layer 4, the fourth layer 5 and the fifth layer 6 is 10 microns, 30 microns, 50 microns, 80 microns and 100 microns in sequence.

Note that the number of layers of the porous ceramic substrate in the present invention is not limited to the above number of layers, and may be two, three, four, six, seven, or the like. The particle size of the ceramic material for each layer is not limited to the above value. In short, the porous ceramic matrix includes at least two layers, and the particle diameters of the ceramic raw materials of the respective layers are arranged in a gradient manner.

In one embodiment, the pore diameters of the layers of the porous ceramic matrix 10 sequentially increase along a direction from the first face 1 to the second face 7. I.e. the first layer has the smallest pore size and the fifth layer has the largest pore size. This arrangement facilitates the gradual directing of the atomized liquid from the second face 7 to the first face 1 during the atomization process. The structure that the pore diameters of the layers are sequentially increased can be realized by matching pore-forming agents with different particle diameters in the preparation process of the porous ceramic matrix 10, namely, the ceramic raw material of the first layer is matched with the pore-forming agent with small particle diameter, the ceramic raw material of the second layer is matched with the pore-forming agent with larger particle diameter, the ceramic raw material of the third layer is matched with the pore-forming agent with larger particle diameter, and the like.

Among them, the ceramic raw material is preferably diatomaceous earth, quartz sand and alumina.

Referring to fig. 2, the ceramic atomizing core of some embodiments includes a porous ceramic matrix 10; and a heating element 20, wherein the porous ceramic base 10 is the porous ceramic base of the above embodiment, and the heating element 20 is attached to the first surface 1 of the porous ceramic base 10.

The heating element 20 is preferably a metal layer, the metal constituting the metal layer is preferably Ti, ag, cr, ni, fe, al metal or alloy thereof, the metal layer is plated on the first surface 1 of the porous ceramic substrate, the metal layer may be in the form of a wire, such as a strip wire or a wire, one end of the strip wire or the wire is a positive electrode, the other end of the strip wire or the wire is a negative electrode, the metal layer may be in the form of a film, and the edge of the film is provided with the positive electrode and the negative electrode.

The plating process for plating the heating element 20 on the first surface 1 of the porous ceramic base 10 is preferably a vacuum sputtering plating process. People verify that the atomizing core obtained on the porous ceramic matrix in a vacuum sputtering coating mode has the advantages of good atomizing effect, high temperature resistance, corrosion resistance, product quality improvement, product service life prolonging and the like, but the sputtering coating porous ceramic has extremely high requirements on the ceramic surface, so that the yield of the atomizing core is low, and the atomizing effect of the product is inconsistent.

The porous ceramic substrate 10 has high surface flatness, and has both pore size and porosity, and is very suitable for a vacuum sputtering coating process. Based on above-mentioned porous ceramic base member 10, adopt vacuum sputtering coating process to plate at porous ceramic base member 10 first face 1 and establish heat-generating body 20, make the pottery generate heat the core, can make porous ceramic base member 10 and heat-generating body 20 perfect adaptation, the phenomenon that heat-generating body 20 breaks away from porous ceramic base member 10 in the very big reduction use. No core burnt phenomenon is caused after 3000-mouth suction.

As another embodiment of the heat-generating body 20, a graphene material may also be used.

As another embodiment of the attachment method of the heating element 20 to the porous ceramic base 10, an adhesive layer may be first screen-printed on one surface of the heating element 20, then the heating element 20 may be placed on the porous ceramic base 10, the adhesive layer may be attached to the first surface 1 of the porous ceramic base 10, and then the porous ceramic base 10 may be sintered to attach the adhesive layer to the first surface 1. The melting point of the adhesive used for the bonding layer is higher than the heating temperature of the atomizing core during operation, so as to ensure that the adhesive does not melt during atomizing heating, and for example, a metal or alloy adhesive can be used.

One preparation method of the ceramic atomizing core comprises the following steps: first, a porous ceramic substrate shown in fig. 1 is prepared; and then, uniformly sputtering a metal material to the first surface of the porous ceramic matrix by a vacuum sputtering coating process to form a heating body, thereby preparing the ceramic atomizing core.

Wherein the parameters of the sputtering coating process are as follows: background vacuum degree of 1.0x10 ^-3 And the deposition pressure is 0.1-2 Pa, and the deposition temperature is 0-300 ℃.

Referring to fig. 3, the step of preparing the porous ceramic substrate therein includes:

step S1, cleaning

Weighing a certain amount of ceramic raw materials, preferably diatomite, quartz sand or alumina, putting the ceramic raw materials into a scrubbing machine, adding water to form slurry, flowing into a dispersion machine for dilution, and removing coarse sand or raw materials with larger particle size;

step S2, removing iron oxide

Adding the raw materials treated in the step S1 into a high-speed stirrer, adding gravity magnetic water to generate static friction, and removing impurities such as ferric oxide and the like by utilizing the negative charge characteristic of the impurities such as ferric oxide and the like;

s3, screening to obtain ceramic raw materials with different gradient particle sizes

Removing fine particles from the raw material processed in the step S2 by using ultrasonic vibration screening equipment to obtain high-quality raw materials with different levels and uniform particle size of each level, specifically five layers of materials which are respectively 10 microns, 30 microns, 50 microns, 80 microns and 100 microns;

step S4, roasting

Further roasting the raw materials treated in the step S3 at 400-800 ℃, removing substances such as carbon, bound water and the like, and then naturally cooling to room temperature;

step S5, mixing the ceramic raw materials with different grain diameters with sintering aids respectively to form ceramic raw materials containing the aids with different grain diameters

Respectively putting the raw materials of each layer processed in the step S4 into a mixer, adding sintering aids such as a binder, a sintering aid, a dispersant, a pore-forming agent, a plasticizer and the like, mixing, and respectively granulating by using a granulator to obtain ceramic raw materials containing the aids with different particle sizes;

the usable adhesive comprises but is not limited to paraffin, the usable plasticizer comprises but is not limited to PE (polyethylene), PVC (polyvinyl chloride), PVA (polyvinyl alcohol) and the like, the plasticizer and the adhesive can keep a blank body not to deform, ceramic defects generated by thermal stress can be reduced, and the yield of the porous ceramic atomizing core can be improved;

the pore-forming agent which can be used includes but is not limited to graphite powder and PMMA (polymethyl methacrylate), the pore-forming agent plays a role in controlling the aperture and porosity of the porous ceramic matrix to obtain a mutually-penetrated pore channel structure in the porous ceramic matrix, and ceramic raw materials with different particle sizes are preferably matched with the pore-forming agent with different particle sizes to ensure that the aperture of each layer is different;

sintering aids that can be used include, but are not limited to, glass powder, clay, which act to lower the sintering temperature and promote densification of the ceramic body;

the usable dispersing agent comprises stearic acid, and the dispersing agent plays a role in fully mixing and dispersing the powder and maintaining uniformity;

s6, according to the grain size of the ceramic raw material, the ceramic raw materials with various grain sizes and containing the auxiliary agent are configured in a layered mode, and a layered blank is formed through compression molding

Firstly, putting a ceramic raw material containing an auxiliary agent with the particle size of 100 micrometers into a mould, and pressing to form a green blank sheet I;

putting the first green sheet into a press die, uniformly covering a layer of ceramic raw material containing an auxiliary agent with the particle size of 80 microns on the first green sheet, and pressing into a second green sheet;

putting the green blank sheet II into a press mold, uniformly covering a layer of ceramic raw material containing the auxiliary agent and having the particle size of 50 micrometers on the green blank sheet II, and pressing into a green blank sheet III;

putting the green blank sheet III into a press mold, uniformly covering a layer of ceramic raw material containing the auxiliary agent with the particle size of 30 micrometers on the green blank sheet III, and pressing into a green blank sheet IV;

putting the green blank sheet IV into a press mold, uniformly covering a layer of ceramic raw material containing an auxiliary agent and having a particle size of 10 micrometers on the green blank sheet IV, and pressing to obtain a layered blank body with a five-layer structure;

s7, removing the glue from the layered blank to obtain a ceramic precursor

Placing the layered blank obtained in the step S6 in a degreasing furnace for binder removal, removing additives such as a plasticizer, a dispersing agent, a pore-forming agent and the like in the layered blank to obtain a ceramic precursor, wherein the temperature is slowly increased in the temperature range due to a large amount of gas generated in the decomposition process of the additives, so that the blank is prevented from being damaged by the additives such as the plasticizer and the like in the decomposition process;

the gel discharging temperature rising system of one embodiment comprises the following steps: raising the temperature from room temperature to 600 ℃, wherein the raising rate from room temperature to 200 ℃, from 200 ℃ to 400 ℃, and from 500 ℃ to 600 ℃ is less than 1 ℃/min;

step S8, sintering

And (4) placing the ceramic precursor obtained in the step (S7) into a sintering furnace for sintering, wherein the temperature rise system is determined as follows: the temperature is between room temperature and 900 ℃,2 to 5 ℃/min and the temperature is kept for 30min;900 ℃ to the sintering temperature, 2 to 10 ℃/min, and the sintering temperature is kept for 2 hours. The sintering process ensures that the sintered ceramic has regular and non-deformable appearance and better mechanical property.

According to the preparation method, firstly, the purity of the raw materials is improved by using a cleaning process, in addition, the raw materials with high quality and different levels and uniform particle size of each level are obtained by screening through an ultrasonic vibration method, then the raw materials with large particle size are filled into a mould for pressing and forming, then a proper amount of the raw materials with small particle size are weighed for further pressing to form a blank body with a layered structure, the blank body with the layered structure is placed in a sintering furnace for high-temperature binder removal and sintering, and the ceramic of each layer is perfectly combined through the action of a sintering aid in the pressing process and the sintering process to obtain the layered porous ceramic matrix with different particle sizes and pore sizes of each layer. The porous ceramic matrix is subjected to a vacuum sputtering coating process to obtain the ceramic atomizing core, wherein a layer of metal heating element is plated on the surface with small particle size of the ceramic matrix, and the ceramic matrix of the obtained atomizing core is perfectly combined with the heating element, so that the failure phenomenon caused by the fact that the heating element is separated from the ceramic matrix in the using process of the atomizing core can be greatly reduced.

And (3) performance testing:

the consistency of the film resistance value and the service life of the ceramic atomizing core prepared by the method are measured. Wherein, the film resistance is tested by a scratch method, and the service life is tested by a simulation real person pumping mode of pumping 3 to stop 8 machines. The consistency of the film resistance value is kept within +/-0.05 omega in the determination result, and the atomizing core is not pasted by suction at 3000 mouths, which shows that the binding force of the heating element and the porous ceramic matrix of the ceramic atomizing core prepared by the method is good, and the phenomenon that the heating element is separated from the porous ceramic matrix is not easy to occur.

In addition, in the ceramic atomizing core, the heating body is used for surface heating, so that the atomized smoke is large and fine.

The present invention has been described in detail with reference to the specific embodiments, and the detailed description is only for assisting the understanding of the present invention by those skilled in the art, and is not to be construed as limiting the scope of the present invention. Various modifications, equivalent changes, etc. made by those skilled in the art under the spirit of the present invention shall be included in the protection scope of the present invention.

Claims

1. A porous ceramic matrix, characterized by: the porous ceramic base body is of a layered structure and is provided with a first surface and a second surface, the second surface is opposite to the first surface, and the grain sizes of the ceramic raw materials of all layers of the porous ceramic base body are sequentially increased along the direction from the first surface to the second surface.

2. A porous ceramic matrix according to claim 1, wherein: the pore diameters of the layers of the porous ceramic base body increase in order along the direction from the first surface to the second surface.

3. A porous ceramic matrix according to claim 1, wherein: the grain size of the ceramic raw material of the layer where the first face is located is 10 microns, and the grain size of the ceramic raw material of the layer where the second face is located is larger than 80 microns.

4. A ceramic atomizing core, comprising:

a porous ceramic matrix according to any one of claims 1 to 3; and

a heating element attached to the first surface of the porous ceramic base.

5. The ceramic atomizing core according to claim 4, wherein the heating element is a metal layer, and the metal layer is plated on the first surface of the porous ceramic base.

6. A method for preparing a ceramic atomizing core according to claims 4 to 5, characterized in that it comprises the following steps:

preparing the porous ceramic matrix; and

and uniformly sputtering a metal material to the first surface of the porous ceramic matrix by using a vacuum sputtering coating process to form the heating element.

7. The method according to claim 6, wherein the step of preparing the porous ceramic matrix comprises:

screening to obtain ceramic raw materials with different gradient particle sizes;

respectively mixing ceramic raw materials with different particle sizes with a sintering aid to form ceramic raw materials containing the aid;

according to the grain size of the ceramic raw material, the ceramic raw materials with various grain sizes and containing the auxiliary agent are configured in a layered mode, and a layered blank is formed through compression molding;

and (4) removing the glue from the layered blank, and sintering to obtain the porous ceramic matrix.

8. The method of preparing according to claim 7, wherein the step of preparing the porous ceramic matrix further comprises: before the ceramic raw material containing the auxiliary agent is formed, the ceramic raw material is cleaned, and then the ceramic raw material is roasted at 400-800 ℃.

9. The preparation method of claim 7, wherein the ceramic raw material is selected from the group consisting of diatomaceous earth, quartz sand, and alumina, the ceramic raw material obtained by screening has a gradient particle size of 10 microns, 30 microns, 50 microns, 80 microns, and 100 microns, and the sintering aid comprises a plasticizer, a binder, a dispersant, a pore former, and a sintering aid.

10. The method of claim 7,

the temperature rising system of the binder removal is as follows: raising the temperature from room temperature to 600 ℃, wherein the raising rate from room temperature to 200 ℃, from 200 ℃ to 400 ℃, and from 500 ℃ to 600 ℃ is less than 1 ℃/min;

the temperature rising system of sintering is as follows: heating the mixture from room temperature to 900 ℃ at the speed of 2-5 ℃/min, and keeping the temperature for 30min; heating from 900 ℃ to the sintering temperature at the speed of 2-10 ℃/min, and preserving the heat for 2h.