阅读说明：本技术 电加热发热盘及其制备方法 (Electric heating plate and preparation method thereof ) 是由 程克勇 李寿林 于 2021-09-17 设计创作，主要内容包括：本发明涉及一种电加热发热盘,其特征在于：包括用于加热的铝基板,所述铝基板上用于与加热容器贴合起到导热作用的第一表面上设有螺旋槽,所述螺旋槽的深度在0.05-0.2mm,槽距在0.2-1mm,槽宽在0.1-0.5 mm,所述铝基板的第一表面上覆设有导热涂层,所述导热涂层的涂料嵌在螺旋槽内,所述导热涂层表面平齐或高于铝基板的第一表面；本发明电加热发热盘结构简单、制作成本低,有利于减少导热涂层被磨损而影响加热效率。(The invention relates to an electric heating plate, which is characterized in that: the aluminum substrate is used for heating, a spiral groove is formed in the first surface, which is used for being attached to a heating container and has a heat conduction effect, of the aluminum substrate, the depth of the spiral groove is 0.05-0.2mm, the groove distance is 0.2-1mm, the groove width is 0.1-0.5 mm, a heat conduction coating is covered on the first surface of the aluminum substrate, paint of the heat conduction coating is embedded in the spiral groove, and the surface of the heat conduction coating is flush with or higher than the first surface of the aluminum substrate; the electric heating plate has simple structure and low manufacturing cost, and is beneficial to reducing the influence of the abrasion of the heat-conducting coating on the heating efficiency.)

1. An electric heating dish that generates heat which characterized in that: the aluminum substrate comprises an aluminum substrate for heating, wherein a spiral groove is formed in a first surface, which is used for being attached to a heating container and has a heat conduction effect, of the aluminum substrate, the depth of the spiral groove is 0.05-0.2mm, the groove distance is 0.2-1mm, the groove width is 0.1-0.5 mm, a heat conduction coating is covered on the first surface of the aluminum substrate, a coating of the heat conduction coating is embedded in the spiral groove, and the surface of the heat conduction coating is flush with or higher than the first surface of the aluminum substrate.

2. An electrically heated heat generating tray according to claim 1, characterized in that: the flatness tolerance of the surface of the heat-conducting coating and the first surface of the aluminum substrate is less than 0.08 mm.

3. An electrically heated heat generating tray according to claim 1, characterized in that: the depth of the spiral groove is 0.10mm, the groove distance is 0.6mm, and the groove width is 0.35 mm.

4. An electrically heated heat generating tray according to claim 1, 2 or 3, characterized in that: the heat conducting coating is formed on the first surface of the aluminum substrate through screen printing or spraying.

5. An electrically heated heat generating tray according to claim 1 or 2, characterized in that: the spiral groove is replaced by a concentric circular groove, the depth of the groove is 0.05-0.2mm, the distance of the groove is 0.2-1mm, and the width of the groove is 0.1-0.5 mm.

6. An electrically heated heat generating tray according to claim 1, 2 or 3, characterized in that: the second surface of the aluminum substrate is provided with an electric heating pipe which is spirally arranged; the second surface of the aluminum substrate is provided with a spiral channel, and an electric heating pipe is embedded in the channel.

7. An electrically heated heat generating tray according to claim 1, 2 or 3, characterized in that: the spiral groove is formed by turning, and the heat-conducting coating is a coating with graphene and heat-conducting metal powder.

8. An electrically heated heat generating tray according to claim 1, 2 or 3, characterized in that: the center of the first surface of the aluminum substrate is provided with a circle with the diameter of 10-35mm, the circle is not covered with a heat conduction coating, the shape of the heat conduction coating is in a circle shape, a circular ring shape or a net shape, and the heat conduction coating accounts for 30-100% of the area of the first surface of the aluminum substrate; the aluminum substrate is 2-6mm thick and is rectangular or circular.

9. A method of manufacturing an electrically heated hot plate according to any one of claims 1 to 3, characterized in that: the method comprises the following steps:

(1) preparing a spiral groove with the depth of 0.05-0.2mm, the groove distance of 0.2-1mm and the groove width of 0.1-0.5 mm on the first surface of the aluminum substrate for heating by adopting a turning method;

(2) and coating the heat-conducting coating mixture in a spiral groove on the first surface of the aluminum substrate by adopting a screen printing or spraying process, and then baking for 10-20min at 280 +/-20 ℃ to obtain the electric heating plate.

10. The method of manufacturing an electrically heated hot plate according to claim 9, characterized in that: and (3) the heat-conducting coating mixture in the step (2) is composed of graphene, heat-conducting metal powder, high-temperature-resistant ink, a dispersing agent and water.

The technical field is as follows:

the invention relates to an electric heating plate and a preparation method thereof, and the electric heating plate can be used for heating glass containers, steam heating appliances or cookers and the like.

Background art:

the heating plate in the prior art directly adopts an electric heating pipe, or a stainless steel plate is fixed on the electric heating pipe, or a heating surface with the unevenness smaller than 0.1mm and the smoothness more than 5 is ground on the surface of an aluminum substrate (a third scheme), or a heat-conducting coating containing metal powder materials is coated and printed after the third scheme (the coating thickness is generally 5-15 um), and then the heating plate is baked and molded at high temperature.

The heating surface of the aluminum substrate is easy to scratch in the use process of the third scheme, so that the heating efficiency is influenced; in the fourth scheme, when the glass cup is used, the bottom of the glass cup and the like rub the surface of the heating plate with the heat conducting coating, and the coating falls off in a short time due to the fact that the bottom of the glass cup is very hard (test method: 1300ml of water with the temperature of 20 ℃ is filled in a heating container, the heating container is placed on a heating base with the heating plate to be electrified for working, after the water is boiled, a power supply is cut off, the heating container is immediately and naturally placed on the heating base, the heating container rotates leftwards and rightwards for 45 degrees in 1 cycle of 2 seconds, and after 100 cycles are carried out, the coating of the heating plate falls off greatly), the appearance is influenced, and the heating speed is also influenced (the heating speed is increased from 13 minutes of original heating to boiling to 14-15 minutes).

In order to realize wear resistance of the coating and not influence the heating efficiency, the applicant carries out tests and verifications of various schemes, such as spraying wear-resistant high-temperature ceramic oil or teflon on the heating surface of the aluminum substrate of the third scheme, brazing a stainless steel plate with the thickness of 0.2-0.3mm, researching high-temperature paint with high temperature resistance and wear resistance, processing technology and the like, but the third scheme can not achieve satisfactory effect, or can not achieve the requirement of the heating efficiency, or the coating is easy to drop, or the manufacturing cost is high.

The invention content is as follows:

in view of the above-mentioned defects in the prior art, an object of the present invention is to provide an electric heating plate, which has a simple structure and a low manufacturing cost, and is beneficial to reducing the influence of the heat-conducting coating layer being worn and falling off on the heating efficiency.

The invention discloses an electric heating plate, which is characterized in that: the aluminum substrate comprises an aluminum substrate for heating, wherein a spiral groove is formed in a first surface, which is used for being attached to a heating container and has a heat conduction effect, of the aluminum substrate, the depth of the spiral groove is 0.05-0.2mm, the groove distance is 0.2-1mm, the groove width is 0.1-0.5 mm, a heat conduction coating is covered on the first surface of the aluminum substrate, a coating of the heat conduction coating is embedded in the spiral groove, and the surface of the heat conduction coating is flush with or higher than the first surface of the aluminum substrate.

Furthermore, the flatness tolerance of the surface of the heat-conducting coating and the first surface of the aluminum substrate is less than 0.08 mm.

Furthermore, the depth of the spiral groove is 0.10mm, the groove pitch is 0.6mm, and the groove width is 0.35 mm.

Further, the heat conducting coating is formed on the first surface of the aluminum substrate through screen printing or spraying.

Furthermore, the spiral groove is replaced by a concentric circular groove, the depth of the groove is 0.05-0.2mm, the distance of the groove is 0.2-1mm, and the width of the groove is 0.1-0.5 mm.

Furthermore, the second surface of the aluminum substrate is provided with an electric heating tube which is spirally arranged.

Further, the spiral groove is formed by turning, and the heat-conducting coating is a coating with graphene and heat-conducting metal powder.

Furthermore, the center of the first surface of the aluminum substrate is provided with a circle with the diameter of 10-35mm, and the heat conduction coating is not covered, and is in a shape of a circle, a circular ring or a net.

Furthermore, the thickness of the aluminum substrate is 2-6mm, and the aluminum substrate is a rectangular or circular plate.

The invention also provides a preparation method of the electric heating plate, which comprises the following steps:

(1) preparing a spiral groove with the depth of 0.05-0.2mm, the groove distance of 0.2-1mm and the groove width of 0.1-0.5 mm on the first surface of the aluminum substrate for heating by adopting a turning method;

(2) and coating the heat-conducting coating mixture in a spiral groove on the first surface of the aluminum substrate by adopting a screen printing (the mesh number of a screen printing plate is between 100 and 200) or spraying process, and then baking at the temperature of 280 +/-20 ℃ for 10-20min to obtain the electric heating plate. Preferably, the electrostatic dust removal air knife is adopted to remove dust of the aluminum substrate before printing, so that interference of dust in the printing process is reduced.

Further, the heat-conducting coating mixture in the step (2) is composed of graphene, heat-conducting metal powder, high-temperature-resistant ink, a dispersing agent and water, and comprises the following components in percentage by mass: 1-6% of graphene, 15-30% of heat-conducting metal powder, 60-92% of printing ink and 2-4% of a dispersing agent and water. The preparation method comprises the following specific steps of 1) diluting a dispersing agent with water according to the volume ratio of 1:500, 2) adding a proper amount of graphene into the diluted liquid for dispersing, and 3) adding the dispersed graphene liquid into the high-temperature-resistant ink; 4) and adding the debugged graphene-containing ink into heat-conducting metal powder with particles of 800nm to obtain a heat-conducting coating mixture.

Further, the dispersing agent is sodium dodecyl sulfate, and the heat-conducting metal powder includes, but is not limited to, copper powder, aluminum powder or alloy powder capable of conducting heat.

Further, the heat-conducting coating mixture is baked at a high temperature to form a heat-conducting coating in the spiral groove, the heat-conducting coating is tightly combined with the aluminum substrate, and the surface of the heat-conducting coating is flush with or higher than the first surface of the aluminum substrate, preferably flush with the first surface of the aluminum substrate.

Furthermore, the central part of the first surface of the aluminum substrate is provided with a round non-coated heat-conducting coating mixture with the diameter of 10-35mm, so that the center of the glass cup is higher in the grinding process, and the glass cup is firstly ground to the position of the most center of the surface of the heating plate.

The electric heating plate has the advantages that: firstly, the processing technology for processing the spiral groove on the first surface (heating surface) of the aluminum substrate and coating the heat-conducting coating is simple, and the manufacturing cost is low; the coating of the heat-conducting coating is embedded in the spiral groove, so that the contact area between the coating of the heat-conducting coating and the surface of the aluminum substrate is greatly increased, and the coating firmness of the coating is obviously improved; the surface of the heat-conducting coating is flush with or higher than the first surface of the aluminum substrate, so that the contact area between the heat-conducting coating or the first surface of the aluminum substrate and the bottom surface of the heating container is ensured, and the heating efficiency is ensured; when the surface of the heat-conducting coating is flush with the first surface of the aluminum substrate, the coating (the surface of the coating in the groove) with the heat-conducting coating, which is in contact with the bottom surface of the heating container, and the thread (the top surface of the groove wall body) of the aluminum substrate are in contact with the bottom surface of the heating container, so that even if the heating container made of glass and the like continuously rubs, the groove wall body is firstly contacted or worn due to the higher hardness of the aluminum substrate, the coating in the spiral groove can be prevented from being worn, the friction force can be well reduced due to the lubricating property formed by graphene in the coating, the attractiveness of the surface of the electric heating disc is not influenced, the same contact area with the bottom surface of the heating container is always kept, and the heating efficiency is favorably ensured; even if the aluminum-based aluminum or aluminum alloy screw thread is used for a long time, the aluminum-based aluminum or aluminum alloy screw thread (namely, the wall body of the groove, which plays a role of a framework) is worn firstly and then is positioned on the surface of the coating in the groove, so that the abrasion loss of the coating is greatly reduced, the wear has surface consistency, the coating in the groove can still be ensured not to fall off, the heating efficiency can be still achieved after the aluminum-based aluminum or aluminum alloy screw thread is used for a long time, and the service life of the aluminum-based aluminum or aluminum alloy screw thread is longer.

Description of the drawings:

FIG. 1 is a schematic view of the front view of the electric heating plate of the present invention;

FIG. 2 is a schematic view of a partial cross-sectional configuration of the embodiment of FIG. 1;

FIG. 3 is a schematic view of another embodiment of FIG. 1 in partial cross-sectional configuration;

fig. 4 is a schematic view of the structure of the electric heating plate in use.

The specific implementation mode is as follows:

the process of the present invention is further illustrated in detail by reference to the following examples. It should be noted that the protection scope of the present invention should include, but not be limited to, the technical contents disclosed in the present embodiment.

The electric heating plate comprises an aluminum substrate 1 for heating, wherein the aluminum substrate 1 can be made of die-cast aluminum or aluminum alloy, the thickness of the aluminum substrate can be 1-10mm, preferably 2-6mm, the cross section of the aluminum substrate can be rectangular or circular, the size of the aluminum substrate is not limited, the electric heating plate of the aluminum substrate can be used for heating containers such as glass cups, steam heating appliances or pots, and the electric heating plate is usually fixedly arranged in a heating base A2 for use.

The aluminum substrate 1 is provided with the spiral groove 3 on the first surface 2 which is used for being attached to the heating container A1 to play a role in heat conduction, the first surface 2 is directly contacted with the bottom surface of the heating container, the first surface 2 and the spiral groove 3 can be formed by turning (the smoothness of the first surface 2 is higher than V5, and the smoothness of the spiral groove 3 is lower than V4), and the turning manufacturing cost is low; the first surface 2 may be a flat surface, a conical surface or a spherical surface, but is preferably a flat surface, so that the processing of the aluminum substrate 1 and the processing of the bottom surface of the heating container a1 are simple.

As shown in fig. 2 and 3, the depth of the spiral groove 3 (i.e. the height difference between the first surface 2 and the groove bottom) may be 0.05-0.2mm, the distance between the grooves (i.e. the center distance between adjacent grooves) is 0.2-1mm, the width of the groove is 0.1-0.5 mm, the cross-sectional shape of the spiral groove 3 may be rectangular, trapezoidal, etc., and chamfers may be provided at both the groove opening and the groove bottom.

The depth of the spiral groove 3 can be 0.08-0.12mm, the groove distance is 0.4-0.8mm, the groove width is 0.15-0.4 mm, the optimum spiral groove 3 depth in the trial and error is 0.10mm, the groove distance is 0.6mm, and the groove width is 0.35 mm.

The first surface of the aluminum substrate is covered with the heat-conducting coating 4, the covering of the heat-conducting coating 4 on the first surface of the aluminum substrate herein does not only mean that only the heat-conducting coating 4 on the first surface has paint, but comprises a coating having a thermally conductive coating 4 in the area covered by the first surface, the coating 5 of the thermally conductive coating also comprising a part embedded in the helical groove 3, the surface 6 of the heat conducting coating is flush with or higher than the first surface 2 of the aluminum substrate, as shown in fig. 2 and 3, the thermally conductive coating surface 6, i.e. the uppermost surface of the coating, for the embodiment of fig. 2, the heating surfaces comprise the first surface 2 of the aluminum substrate and the thermally conductive coating surface 6, for the embodiment of fig. 3, the heating surface is a thermally conductive coating surface 6, for the embodiment of fig. 3, the embodiment of fig. 2 may be formed during the use process, and both embodiments have the characteristics of better heat conduction efficiency and difficult coating falling off.

Through the fact that the surface 6 of the heat-conducting coating is flush with or higher than the first surface 2 of the aluminum substrate, the fact that the surface 6 of the heat-conducting coating is flush with the first surface 2 of the aluminum substrate is a better technical scheme, and in the technical scheme, the coating (located on the coating surface in the groove, namely the surface 6 of the heat-conducting coating) with the heat-conducting coating, which is in contact with the bottom surface of the heating container, and the threads (namely the top surface of the groove wall body) of the aluminum substrate are adopted, as shown in fig. 2, even if the heating container made of glass and the like continuously rubs, the groove wall body is firstly contacted or worn due to the higher hardness of the aluminum substrate, so that the coating in the spiral groove can be ensured not to be worn, the attractiveness of the surface of the electric heating disc is not affected, meanwhile, the same contact area with the bottom surface of the heating container is always kept, and the heating efficiency is favorably ensured; even if the aluminum-based aluminum or aluminum alloy screw thread is used for a long time, the aluminum-based aluminum or aluminum alloy screw thread (namely, the wall body of the groove, which plays a role of a framework) is worn firstly and then is positioned on the surface of the coating in the groove, so that the abrasion loss of the coating is greatly reduced, the wear has surface consistency, the coating in the groove can still be ensured not to fall off, the heating efficiency can be still achieved after the aluminum-based aluminum or aluminum alloy screw thread is used for a long time, and the service life of the aluminum-based aluminum or aluminum alloy screw thread is longer.

In order to better realize that the surface 6 of the heat-conducting coating is flush with the first surface 2 of the aluminum substrate, a scraper blade can be used for horizontally scraping a knife on the first surface 2 of the aluminum substrate after the heat-conducting coating is printed or sprayed by screen printing, so that the coating higher than the first surface of the aluminum substrate is scraped.

For the embodiment that the surface 6 of the heat-conducting coating is higher than the first surface 2 of the aluminum substrate, the coating of the heat-conducting coating is embedded in the spiral groove, so that the firmness of the coating higher than the first surface 2 of the aluminum substrate is higher, and the embodiment has the advantages of ensuring that the heating efficiency and the coating are not easy to drop.

The heat-conducting coating 4 can be coated and printed on the first surface of the aluminum substrate by adopting a screen printing process, the shapes of the screen-printed coatings can be various, and preferably, the screen-printed coatings are in a net shape, a grid shape, a circular shape or a circular ring shape; the heat-conducting coating 4 can also be directly brushed on the first surface of the aluminum substrate by adopting a brush, or can be coated on the first surface of the aluminum substrate by spraying or the like; the heat conducting coating 4 can occupy 30-100% of the area of the first surface 2 of the aluminum substrate.

The material of the heat-conducting coating can be any existing coating capable of conducting heat, the heat-conducting coating can be a coating with heat-conducting metal powder and graphene, the heat-conducting metal powder can be copper powder or aluminum powder, and the like, high-temperature ink is also contained in the formula of the heat-conducting coating, and the mass ratio of the heat-conducting metal powder to the high-temperature ink is 15-30%, but the heat-conducting coating is not limited to the above. The lubricating principle of graphene in the coating is not completely the same as the action mode of a common anti-wear additive, namely the molecular particles of the graphene are very small, strong intermolecular action force is possessed between graphene sheet layers, and the friction coefficient is greatly reduced, so that the addition of the graphene in the coating not only increases the heat conduction effect, but also obviously improves the anti-wear and lubricating effects of the coating.

The flatness tolerance between the surface of the heat-conducting coating and the first surface of the aluminum substrate is less than 0.08mm, and the preferable flatness tolerance is less than 0.05mm, and it is ensured that the flatness tolerance between the surface of the heat-conducting coating and the first surface of the aluminum substrate is less than 0.08mm, and when the first surface of the aluminum substrate is lathed (before the grooving of the spiral groove 3), the flatness tolerance is required to be less than 0.08mm, which can be easily ensured when the heat-conducting coating is silk-screen printed, the reason why the flatness tolerance between the surface of the heat-conducting coating and the first surface of the aluminum substrate is less than 0.08mm (or 0.05 mm) is that the flatness tolerance is also ensured to be less than 0.05mm by machining the bottom surface of the heating container, so that the contact area between the first surface of the aluminum substrate, the surface of the heat-conducting coating and the bottom surface of the heating container is large, and the improvement and the guarantee of the heating efficiency are facilitated.

For how to connect the electric heating tube 7 to the second surface of the aluminum substrate (i.e. the surface opposite to the first surface 2), the electric heating tube 7 arranged spirally can be directly fixed on the second surface of the aluminum substrate; or, a spiral channel (not shown in the figure) may be arranged on the second surface of the aluminum substrate, and the electric heating tube 7 is embedded in the channel, so that the second scheme is adopted to make the contact surface between the electric heating tube 7 and the aluminum substrate larger, and the heating efficiency is higher.

The center of the bottom surface of the glass heating container is usually concave upwards, and the center position of the bottom surface of the glass heating container is not contacted with the aluminum substrate, so that the center part of the first surface of the aluminum substrate is provided with a circle with the diameter of 10-35mm, and the heat-conducting coating is not covered on the circle, so that the heat-conducting coating is not needed at the center position, and the coating of the heat-conducting coating is saved.

The spiral groove 3 is turned on the first surface 2 of the aluminum substrate, and of course, other processing equipment or processing technology can be used to process the concentric circular groove, the spiral groove is identical to the concentric circular groove in the field of mechanical manufacturing, and only the spiral groove 3 is convenient and simple to process, so the spiral groove can be replaced by the identical concentric circular groove, the depth of the groove is 0.05-0.2mm, the distance between the grooves is 0.2-1mm, and the width of the groove is 0.1-0.5 mm, and other embodiments are also applicable to the concentric circular groove.

The preparation method of the electric heating plate comprises the following steps:

(1) preparing a spiral groove with the depth of 0.1mm, the groove distance of 0.6mm and the groove width of 0.35mm on the first surface of the aluminum substrate for heating by adopting a turning method, wherein the unevenness of the spiral groove is less than 0.05 mm;

(2) preparing a heat-conducting coating mixture: 1) diluting sodium dodecyl sulfate with water according to the volume ratio of 1:500, 2) adding a proper amount of graphene into the diluted liquid for dispersing, and 3) adding the dispersed graphene liquid into the high-temperature-resistant ink; 4) adding copper powder with particles of 800nm into the debugged graphene-containing ink, wherein the heat-conducting coating mixture comprises the following components in percentage by mass: 5% of graphene, 20% of copper powder, 81% of high-temperature-resistant ink, and 4% of sodium dodecyl sulfate and water.

(3) The heat-conducting coating mixture is coated in the spiral groove on the first surface of the aluminum substrate by adopting screen printing, and the aluminum substrate is subjected to dust removal treatment by adopting an electrostatic dust removal air knife before printing, so that the interference of dust in the printing process is reduced; and (3) coating a circle with the diameter of 20mm at the central part of the first surface of the aluminum substrate, hollowing out the center of the circle, baking at 280 ℃ for 20min, and baking the heat-conducting coating mixture at high temperature to form a heat-conducting coating in the spiral groove, wherein the heat-conducting coating is tightly combined with the aluminum substrate and is flush with the first surface of the aluminum substrate, so that the electric heating plate shown in fig. 2 is obtained.

Comparative example: the electric heating plate of the above embodiment is only replaced by the aluminum substrate with the spiral grooves with the smooth aluminum substrate.

And (3) performance testing: 1. and (3) wear resistance test: 1300ml of water with the temperature of 20 ℃ is filled in the glass, the glass is placed on a heating base with an electric heating plate to work by electrifying, when the water is boiled, the power supply is cut off, the glass is immediately and naturally placed on the heating base, the glass is rotated for 45 degrees leftwards and rightwards by 1 cycle of 2 seconds, after 1000 cycles, the falling-off condition of the coating of the electric heating plate is observed, after a main machine is fully cooled, 1300ml of water with the temperature of 20 ℃ is filled in the glass again, the glass is placed on the main machine to work by electrifying, when the water is boiled, the time length of boiling water is recorded, and the glass is qualified within 1 minute after the time length is longer than that before the test. 2. Testing the heating rate of the electric heating plate: 1300ml of water with the temperature of 20 ℃ and 30 ℃ is filled in the glass cup, the glass cup is placed on a heating base with an electric heating plate to be electrified for working, and the time of the water temperature of 100 ℃ is displayed.

Table 1 shows the data of the abrasion resistance test of examples and comparative examples

Table 2 shows the temperature rise rate test data of examples and comparative examples

The electric heating plate has the advantages that: firstly, the processing technology for processing the spiral groove on the first surface (heating surface) of the aluminum substrate and coating the heat-conducting coating is simple, and the manufacturing cost is low; the coating of the heat-conducting coating is embedded in the spiral groove, so that the contact area between the coating of the heat-conducting coating and the surface of the aluminum substrate is greatly increased, and the coating firmness of the coating is obviously improved; the surface of the heat-conducting coating is flush with or higher than the first surface of the aluminum substrate, so that the contact area between the heat-conducting coating or the first surface of the aluminum substrate and the bottom surface of the heating container is ensured, and the heating efficiency is ensured; when the surface of the heat-conducting coating is flush with the first surface of the aluminum substrate, the coating (the surface of the coating in the groove) with the heat-conducting coating, which is in contact with the bottom surface of the heating container, and the thread (the top surface of the groove wall body) of the aluminum substrate are in contact with the bottom surface of the heating container, so that even if the heating container made of glass and the like continuously rubs, the groove wall body is firstly contacted or worn due to the higher hardness of the aluminum substrate, the coating in the spiral groove can be prevented from being worn, the appearance of the surface of the electric heating disc is not influenced, and meanwhile, the same contact area with the bottom surface of the heating container is always kept, so that the heating efficiency is favorably ensured; even if the aluminum-based aluminum or aluminum alloy screw thread is used for a long time, the aluminum-based aluminum or aluminum alloy screw thread (namely, the wall body of the groove, which plays a role of a framework) is worn firstly and then is positioned on the surface of the coating in the groove, so that the abrasion loss of the coating is greatly reduced, the wear has surface consistency, the coating in the groove can still be ensured not to fall off, the heating efficiency can be still achieved after the aluminum-based aluminum or aluminum alloy screw thread is used for a long time, and the service life of the aluminum-based aluminum or aluminum alloy screw thread is longer.

The coating inserted into the thread groove is wrapped and adsorbed by the surrounding aluminum material to form a compact and tight integral structure, so that the coating can be steamed and boiled for a long time without falling off, and meanwhile, compared with the Teflon or ceramic oil spraying method, the Teflon or ceramic oil spraying method has the advantages that the Teflon or ceramic oil spraying method is a heat insulation material, a certain blocking effect is formed on the heating of the heating plate, the heating efficiency is influenced, and the heat conduction effect is good.

When the surface of the heat-conducting coating is lower than the first surface of the aluminum substrate, the surface of the heat-conducting coating (the surface of the coating in the spiral groove) is not in contact with the bottom surface of the heating container, namely, an air gap and an air interlayer are generated, and the aluminum substrate separates the air interlayer for heat conduction of the bottom surface of the heating container, so that the heating efficiency is reduced.

The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made in accordance with the claims of the present invention should be covered by the present invention.