Cooker

Abstract

The utility model provides a cooker. The cooker comprises a cooker base body and a spraying layer formed on the cooker base body, the spraying layer is a metal layer with an oxide film, the spraying layer comprises an inner layer and an outer layer which are arranged in a stacked mode in the thickness direction of the cooker, the inner layer is arranged on the cooker base body, the outer layer is arranged on the inner layer, and the oxide film is arranged on the inner layer. The porosity of the inner layer is greater than that of the outer layer, and the pore size of the inner layer is greater than that of the outer layer, so that the inner layer and the outer layer construct a spraying layer with a gradient porous structure. According to the cooker provided by the utility model, the cooker has good initial non-stickiness and lasting non-stickiness.

Description

Technical Field

[0001] This utility model relates to the field of cookware technology, specifically to a cookware. Background Technology

[0002] In the traditional cookware industry, to achieve durable non-stick properties, liquid coatings are typically atomized and sprayed onto the substrate surface to form a non-stick layer. These liquid coatings, primarily composed of fluorocarbon resins and siloxane sol-polymers, are characterized by thin film thickness (the non-stick functional film is typically only 10-20 micrometers thick) and uneven film thickness (affected by spraying techniques), which can easily lead to defects such as poor wear resistance and short service life.

[0003] Existing cookware coatings often form a coating in a single way, and then store oil in the pores of the coating to optimize non-stick properties through the principle of oil film non-stick. However, the existing oil film is used up in a short time, which means that the cookware cannot simultaneously have both initial non-stick and long-lasting non-stick properties.

[0004] Therefore, developing cookware that combines initial non-stick properties with long-lasting non-stick properties remains a problem to be solved. Utility Model Content

[0005] Therefore, the purpose of this invention is to provide a cookware that simultaneously possesses both initial non-stick and long-lasting non-stick properties.

[0006] The first aspect of this utility model aims to provide a cookware, wherein the cookware includes a cookware substrate and a coating layer, the coating layer being a metal layer with an oxide film, and the coating layer comprising an inner layer and an outer layer stacked in the thickness direction of the cookware, the inner layer being disposed on the cookware substrate, and the outer layer being disposed on the inner layer, wherein the porosity of the inner layer is greater than that of the outer layer, and the pore size of the inner layer is greater than that of the outer layer, thereby the inner layer and the outer layer constructing a coating layer with a gradient porous structure.

[0007] According to the embodiments of this utility model, the cookware with a gradient porous structure can more effectively store oily substances, such as grease. Thus, in the initial stages of cooking, the gradient porous structure can quickly adsorb and fix the oily substances, forming a uniform oil film with excellent initial non-stick properties during use. During cooking, as the temperature rises and the food is stirred, the stored oily substances are gradually released and replenished to the oil film on the cookware surface, maintaining the continuity and integrity of the oil film. This continuous release characteristic ensures that the cookware maintains good non-stick properties even after prolonged use or multiple cooking sessions, greatly improving its long-lasting non-stick performance. Furthermore, the coating layer is a metal layer with an oxide film (i.e., the metal layer has undergone oxidation treatment). This oxide film has higher hardness and wear resistance than the metal itself, providing effective protection for the oil film. Because the oil film is locked within the pores of the porous structure of the coating layer, it is not easily damaged or lost even under high temperatures or vigorous cooking operations. Therefore, the cookware with the aforementioned coating layer possesses both good initial non-stick properties and long-lasting non-stick properties. Furthermore, the pore distribution between the layers of this invention ensures a tight bond between the layers, thereby enabling the creation of a cookware with excellent bonding strength.

[0008] In some embodiments, the oxide film is located on the outer surface of the metal layer and the inner walls of the pores of the metal layer. This allows for optimization of the overall performance of the coating layer due to the presence of a large amount of oxide film. Specifically, the oxide film tightly covers the outer surface of the metal layer, imparting a certain surface hardness and smoothness to the coating layer. Furthermore, the oxide film covering the inner walls of the pores of the metal layer enhances the mechanical properties, corrosion resistance, and wear resistance of the aluminum layer, ensuring the overall strength and performance of the coating layer with a gradient porous structure. And / or, the oxide film is formed by a high-temperature phase transformation of an amorphous oxide film, resulting in more stable properties and higher hardness. And / or, the oxide film on the inner walls of individual pores of the metal layer has gaps to form the gradient porous structure. This increases the overall hardness, corrosion resistance, and other properties of the coating layer due to the formation of the oxide film, without destroying the intended gradient porosity of the coating layer. And / or, the metal layer is an aluminum layer, a magnesium layer, or an iron layer, and the oxide film is the corresponding metal oxide film. All of these forms enhance the metal layer, resulting in a coating layer with good hardness and wear resistance.

[0009] In some embodiments, the oxide film is an alumina film with various crystal morphologies, including at least an α-crystal morphology. Compared to other crystal morphologies of alumina, the alumina film containing the α-crystal morphology has a more stable crystal phase, higher hardness, and better structural stability, and can resist scratches and corrosion from various corrosive substances. Thus, as the framework of the gradient porous structure, it can ensure structural strength, wear resistance, and acid and alkali resistance. And / or, the thickness of the oxide film on the outer surface of the metal layer is 25 micrometers to 60 micrometers. This thickness can ensure the surface hardness and wear resistance of the cookware. And / or, the hardness of the oxide film is 600 HV to 800 HV. This hardness can resist wear and tear during use, extending the service life of the cookware.

[0010] In some embodiments, the sprayed coating is obtained by anodic hard oxidation of a metal sprayed coating with a gradient pore structure followed by calcination at a temperature of 550°C-600°C.

[0011] In these embodiments, by performing anodic hard oxidation and high-temperature calcination on the metal spray coating with a gradient pore structure to obtain the oxidized and sintered spray coating of the present invention, the three-dimensional gradient porous structure of the spray coating can be constructed by means of the three-dimensional gradient pore structure of the metal spray coating, so that the non-stick performance of the cookware is better.

[0012] In some embodiments, the metal spray coating with a gradient pore structure includes a first sublayer and a second sublayer, wherein the first sublayer is formed as an inner layer of the metal layer and the second sublayer is formed as an outer layer of the metal layer, wherein the porosity of the first sublayer is greater than that of the second sublayer and the pore size of the first sublayer is greater than that of the second sublayer, thereby constructing a metal spray coating with a gradient pore structure from the first sublayer and the second sublayer.

[0013] In these embodiments, the first sublayer forming the inner layer of the spray coating has a larger porosity and larger pores than the second sublayer forming the outer layer of the spray coating. This means that the first sublayer forming the inner layer of the spray coating has more and larger pores than the second sublayer forming the outer layer of the spray coating. This ensures that the pores of each layer of the metal spray coating are as interconnected as possible, so as to form a larger oil storage structure inside the metal spray coating. This ensures the amount of oil stored and the continuous and stable release of grease.

[0014] In some embodiments, the porosity of the first sublayer is 10%-20%, and the pore size of the first sublayer is in the range of 40 micrometers to 50 micrometers, and / or, the porosity of the second sublayer is 5%-10%, and the pore size of the second sublayer is in the range of 10 micrometers to 20 micrometers.

[0015] In these embodiments, the first and second sublayers having the above porosity and pore size can form a metal spray coating with a gradient pore structure, with reasonable pore size and distribution, which is more suitable for storing more oily substances, and the stored oily substances can be continuously and stably released.

[0016] In some embodiments, the spraying method for forming the first sub-layer is arc spraying, and the spraying method for forming the second sub-layer includes plasma spraying, supersonic spraying, or cold spraying.

[0017] In these embodiments, a first sublayer is first formed by arc-spraying filament, followed by a second sublayer formed by plasma spraying, supersonic spraying, or cold spraying particles. By combining different spraying methods, a metal coating with a gradient porosity structure is constructed. This gradient porosity structure forms the basis for a coating with a gradient porous structure, resulting in a gradual transition from porous to dense from the inside out. In this gradient porous structure, especially in the lower layers, a large amount of oil can be stored, and this stored oil can be continuously and stably released through the pores of the upper layers. This allows for the formation of a stable oil film on the surface of the coating, resulting in low surface energy and initial non-stick properties. Since the oil film within the gradient porous structure is protected by the coating layer acting as a framework, it provides long-lasting non-stick properties. Furthermore, although the coating with a gradient porous structure is a multi-layered composite structure, good bonding between its layers can be achieved through material selection and pore size distribution.

[0018] In some embodiments, the material forming the first sub-layer is aluminum wire, and the material forming the second sub-layer is aluminum particles. By sequentially spraying the above-mentioned material combination onto the cookware substrate, a metal spray coating with the above-mentioned pore distribution can be formed, which can meet the requirements of serving as an oil storage skeleton for the cookware.

[0019] In some embodiments, the aluminum wire has a diameter of 1.5 mm to 2.5 mm, and the aluminum particles have a particle size of 80 micrometers to 150 micrometers, and the above specific form can form a metal spray coating with a suitable pore distribution.

[0020] In some embodiments, the thickness of the sprayed coating is 30 micrometers to 100 micrometers.

[0021] In these embodiments, within this thickness range, a suitable gradient porous structure can be formed to store oil while ensuring coating strength, thereby ensuring the non-stick properties of the cookware.

[0022] In some embodiments, the cookware further includes an oily substance filling the gradient porous structure. Pre-filling the gradient porous structure with an oily substance can further improve the initial non-stick performance of the cookware and ensure its long-lasting non-stick performance. Attached Figure Description

[0023] The above and other objects and features of this utility model will become clearer from the following description of embodiments in conjunction with the accompanying drawings, in which:

[0024] Figure 1 This is a cross-sectional structural schematic diagram of a cooker according to an embodiment of the present utility model;

[0025] Figure 2 yes Figure 1 Enlarged structural diagram at point I;

[0026] Figure 3 yes Figure 1 Schematic diagram of the cross-sectional structure at point AA;

[0027] Figure 4 This is a cross-sectional view of a cookware substrate with a metal spray coating having a gradient pore structure according to an embodiment of the present invention.

[0028] Figure 5 yes Figure 4 A magnified structural diagram of point J in the middle.

[0029] Symbol Explanation

[0030] 10. Cookware base;

[0031] 20. Metal spray coating; 21. First sublayer; 22. Second sublayer; 30. Spray coating; 31. Oxide film; 40. Gradient porous structure; 50. Gradient porous structure. Detailed Implementation

[0032] The following detailed descriptions are provided to aid the reader in gaining a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will become apparent upon understanding this disclosure. For example, the order of operations described herein is merely illustrative and is not limited to those orders set forth herein, but may be altered as will become clear upon understanding this disclosure, except for operations that must occur in a specific order. Furthermore, for clarity and conciseness, descriptions of features known in the art may be omitted.

[0033] The features described herein may be implemented in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein are provided only to illustrate some of the many possible ways of implementing the methods, apparatus and / or systems described herein, many of which will become clear upon understanding the disclosure of this utility model.

[0034] As used herein, the term “and / or” includes any one of the associated listed items and any combination of any two or more.

[0035] Although terms such as “first,” “second,” and “third” may be used herein to describe various components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts should not be limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Thus, without departing from the teaching of the examples described herein, the first component, first assembly, first region, first layer, or first part referred to as the first component, first assembly, first region, first layer, or first part may also be referred to as the second component, second assembly, second region, second layer, or second part.

[0036] In the specification, when an element such as a layer, region, or substrate is described as being "on" another element, "connected to," or "mounted to" another element, the element may be directly "on" another element, directly "connected to," or "mounted to" the other element, or one or more other elements may be present in between. Conversely, when an element is described as being "directly on" another element, "directly connected to," or "directly mounted to" another element, no other elements may be present in between.

[0037] The terminology used herein is for describing various examples only and is not intended to limit the invention. Unless the context clearly indicates otherwise, the singular form is intended to include the plural form as well. The terms “comprising,” “including,” and “having” indicate the presence of the described features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof. The term “a plurality” represents any quantity of two or more.

[0038] The directional terms "upper part," "lower part," "inner part," and "outer part" used in this utility model are all based on the orientation of the cookware when it is in normal use. This definition method will help ensure that readers or users can clearly understand the relative positional relationships of the various components and functions, and should not be construed as a limitation of this utility model.

[0039] Unless otherwise defined, all terms used herein, including technical and scientific terms, shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains after understanding the invention. Unless expressly defined herein, terms such as those defined in general dictionaries shall be interpreted as having the same meaning as they have in the context of the relevant field and in the invention, and shall not be interpreted in an idealized or overly formalistic manner.

[0040] Furthermore, in the description of the examples, detailed descriptions of well-known related components or functions will be omitted when it is believed that such detailed descriptions would lead to a vague interpretation of the present invention.

[0041] The following will combine Figure 1 and Figure 5 To describe the cookware provided according to embodiments of the present invention.

[0042] According to an embodiment of the present invention, a cooking utensil is provided, wherein, as... Figure 1 and Figure 3 As shown, the cookware includes a cookware substrate 10 and a coating layer 30 formed on the cookware substrate 10. The coating layer 30 is a metal layer with an oxide film. The coating layer 30 includes an inner layer and an outer layer stacked in the thickness direction of the cookware. The inner layer is disposed on the cookware substrate 10 and the outer layer is disposed on the inner layer. The porosity of the inner layer is greater than that of the outer layer, and the pore size of the inner layer is greater than that of the outer layer. Thus, the inner and outer layers construct a coating layer 30 with a gradient porous structure 50.

[0043] According to the cookware provided in this embodiment, the coating layer 30 with a gradient porous structure 50 can more effectively store oily substances, such as grease. Thus, in the initial stage of cooking, the gradient porous structure 50 can quickly absorb and fix the oily substances, forming a uniform oil film with excellent initial non-stick properties during use. During cooking, as the temperature rises and the food is stirred, the stored oily substances are gradually released and replenish the oil film on the cookware surface, maintaining the continuity and integrity of the oil film. This continuous release characteristic ensures that the cookware maintains good non-stick properties even after prolonged use or multiple cooking sessions, thus greatly improving the cookware's long-lasting non-stick performance. Furthermore, the coating layer 30 is a metal layer with an oxide film (i.e., the metal layer has undergone oxidation treatment). This oxide film has higher hardness and wear resistance than the metal itself, providing effective protection for the oil film. Because the oil film is locked within the pores of the porous structure of the coating layer 30, it is not easily damaged or lost even under high temperatures or vigorous cooking operations. This results in cookware with the aforementioned coating layer 30 exhibiting both good initial non-stick properties and long-lasting non-stick properties. In addition, the pore distribution between the layers in this invention ensures a tight bond between them, thereby obtaining cookware with excellent adhesion.

[0044] In this embodiment of the utility model, the inner layer is disposed (formed) on the cookware substrate 10, and the outer layer is disposed (formed) on the inner layer. It can also be understood that the inner layer is in contact with the cookware substrate 10, and the outer layer is in contact with the inner layer.

[0045] According to this invention, the coating layer 30 is a metal layer with an oxide film, referring to the material properties of the coating layer. The oxide film is located on the outer surface of the metal layer and on the inner walls of the pores of the metal layer, thus optimizing the overall performance of the coating layer 30 due to the presence of a large amount of oxide film. Specifically, the oxide film 31 tightly covers the outer surface of the metal layer, giving the coating layer 30 a certain surface hardness and smoothness. In addition, the oxide film 31 covering the inner walls of the pores of the metal layer can enhance the mechanical properties, corrosion resistance, and wear resistance of the aluminum layer, ensuring the overall strength and performance of the coating layer 30 with its gradient porous structure 50.

[0046] In some embodiments, the oxide film is an oxide film 31 formed by a high-temperature phase transformation of an amorphous oxide film, which has more stable properties and higher hardness.

[0047] In some embodiments, the oxide films on the inner walls of individual pores of the metal layer have gaps to form a gradient porous structure 50. In this way, the overall properties of the coating layer 30, such as hardness and corrosion resistance, can be increased due to the formation of the oxide film, without destroying the intended gradient porosity of the coating layer 30 due to the oxide film.

[0048] As an example, the metal layer can be an aluminum, magnesium, or iron layer, and the oxide film can be a corresponding metal oxide film, namely an aluminum oxide film, a magnesium oxide film, or an iron oxide film. All of these methods can enhance the metal layer, resulting in a coating with good hardness and wear resistance.

[0049] Taking aluminum as an example, the aluminum layer has advantages such as good thermal conductivity, plasticity, and light weight. The aluminum oxide film is located on the outer surface of the aluminum layer and on the inner wall of the pores of the aluminum layer, which strengthens the aluminum layer and enables it to obtain a coating with good hardness and wear resistance.

[0050] In addition, it should be noted that the coating material of this utility model is not limited to aluminum, magnesium or iron layers, but can also be a coating material formed from other easily oxidized metals.

[0051] In some embodiments, the oxide film 31 on the outer surface of the metal layer has a thickness of 25-60 micrometers. This thickness ensures the surface hardness and wear resistance of the cookware. It should be noted that although an oxide film 31 of a certain thickness is formed on the surface of the metal layer, this oxide film 31 is not absolutely dense, allowing molecules of a certain molecular weight to pass through. Oil molecules have very small molecular weights, typically in the nanometer range, and therefore can pass through the oxide film and penetrate into the pores of the metal layer with the oxide film, that is, they can penetrate into the sprayed coating layer 30 with the gradient porous structure 50. In other words, although the oxide film 31 provides a certain degree of protection for the metal layer, because it is not completely barrier to substances, small molecules such as oil molecules can still pass through the oxide film and enter the porous structure of the metal layer and its sprayed coating layer 30.

[0052] In some embodiments, the oxide film 31 has a hardness of 600HV-800HV, which is sufficient to resist wear and tear and extend the service life of the cookware.

[0053] According to this utility model, such as Figure 2 The oxidized and sintered sprayed coating 30 shown is for example... Figure 4 and Figure 5 The metal spray coating 20 shown has a gradient pore structure 40 and is obtained by calcination at a temperature of 550°C-600°C after anodic hard oxidation.

[0054] In these embodiments, by performing anodic hard oxidation and high-temperature calcination on the metal spray coating 20 having a gradient pore structure 40 to obtain the oxidized and sintered spray coating 30 of this invention, a three-dimensional gradient porous structure 50 of the spray coating 30 can be constructed using the three-dimensional gradient pore structure 40 of the metal spray coating, resulting in better non-stick performance of the cookware. By applying a voltage to the surface of the metal spray coating 20 to perform anodic hard oxidation treatment, it reacts with the electrolyte solution, thereby forming a dense alumina film on the surface and in the pores of the metal spray coating 20, which improves the hardness, wear resistance, and corrosion resistance of the metal spray coating 20. Subsequently, high-temperature calcination further consolidates the structure of the alumina film, improving its stability and durability. At high temperatures, residual stress and defects in the alumina film are released and repaired, making it denser and harder. At the same time, high-temperature calcination also helps to make the bond between the alumina film and the metal spray coating 20 stronger.

[0055] In some embodiments, the oxide film 31 is an alumina film with various crystal morphologies, including at least an α-crystal morphology. Compared to other crystal morphologies of alumina, the alumina film containing the α-crystal morphology has a more stable crystal phase, higher hardness, and better structural stability, and can resist scratches and corrosion from various corrosive substances. Thus, as the skeleton part constituting the gradient porous structure, it can ensure structural strength, wear resistance, and acid and alkali resistance. It should be noted that the alumina film obtained by hard anodizing and high-temperature calcination of the metal spray coating inevitably also includes η and γ crystal morphologies.

[0056] It should also be noted that the gradient porous structure 50 is a pore structure with a gradient change, existing within the sprayed coating layer 30. After oxidation and sintering of the metal sprayed coating, the gradient porous structure 50 represents the remaining pore portion before the oxide film grows. Due to the uniformity and thinness of the film growth, although the growth of the oxide film alters the morphology of the original gradient porous structure 40 to some extent, the gradient porous structure 50 still retains the gradient characteristics of the pores. This means that within the sprayed coating layer 30, the pore size and porosity still exhibit a gradual change from the inside out. This gradient characteristic helps optimize the distribution and storage of oily substances, as well as enhance the initial and long-term non-stick properties of the coating. See also Figure 2 and Figure 3 The oxide film in the pores and the gaps between the oxide films that make up the gradient porous structure 50 can be seen.

[0057] According to the present invention, the metal spray coating 20 having a gradient pore structure 40 includes multiple sub-layers stacked in the thickness direction, wherein each sub-layer is constructed with different spraying methods or different materials to form different pores, thereby constructing a metal spray coating 20 having a gradient pore structure 40 from multiple sub-layers.

[0058] In some embodiments, the metal spray coating 20 having a gradient pore structure 40 includes a first sublayer 21 and a second sublayer 22. The first sublayer 21 is formed as an inner layer of the spray coating 30, and the second sublayer 22 is formed as an outer layer of the spray coating 30. The porosity of the first sublayer 21 is greater than that of the second sublayer 22, and the pore size of the first sublayer 21 is greater than that of the second sublayer 22, thereby constructing a metal spray coating 20 having a gradient pore structure 40 by the first sublayer 21 and the second sublayer 22.

[0059] In these embodiments, the first sub-layer 21 forming the inner layer of the spray coating 30 has a larger porosity and larger pores than the second sub-layer forming the outer layer of the spray coating. This means that the first sub-layer 21 forming the inner layer of the spray coating 30 has more and larger pores than the second sub-layer forming the outer layer of the spray coating. In this way, the pores of each layer of the metal spray coating 20 can be made as interconnected as possible to form a larger oil storage structure inside the metal spray coating 20. This ensures the amount of oil stored and the continuous and stable release of grease.

[0060] like Figure 3 and Figure 4 As shown, the metal spray coating 20 includes a first sub-layer 21 and a second sub-layer 22 stacked in the thickness direction of the metal spray coating 20, and the metal spray coating 20 has a gradient pore structure 40.

[0061] As an example, the porosity of the first sublayer 21 is 10%-20%, and the pore size of the first sublayer 21 is in the range of 40 micrometers to 50 micrometers; the porosity of the second sublayer 22 is 5%-10%, and the pore size of the second sublayer 22 is in the range of 10 micrometers to 20 micrometers.

[0062] In these embodiments, the first and second sub-layers having the above porosity and pore size can form a metal spray coating 20 with a gradient pore structure 40, with reasonable pore size and distribution, which is more suitable for storing more oily substances, and the stored oily substances can be continuously and stably released.

[0063] In this embodiment of the invention, the spray coating 30 includes an inner layer (formed by a first sub-layer 21) capable of storing oil and an outer layer (formed by a second sub-layer 22) suitable for controlling the gradual outward overflow of oily substances. Thus, by pre-storing oily substances within it, a continuous and stable oil film can be formed on the cookware during use, ensuring initial and long-lasting non-stick properties. Furthermore, although the spray coating with the gradient porous structure 50 is a multi-layered structure, the layers are tightly bonded together due to the reasonable distribution of pores, thus possessing excellent adhesion.

[0064] In some embodiments, the thickness of each layer can affect the non-stick performance to some extent by influencing the oil storage capacity. For example, the first sub-layer 21 is relatively loose and porous, with a thickness ranging from 25 micrometers to 45 micrometers. If the first sub-layer 21 is too thin, although it can ensure a good bond between the first sub-layer 21 and the cookware substrate, it may not provide enough oil storage pores, thus affecting the non-stick performance. If the first sub-layer 21 is too thick, although it can ensure oil storage pores, it may increase the brittleness of the first sub-layer 21, reducing its crack resistance and abrasion resistance. When the thickness of the first sub-layer 21 is moderate (e.g., 25 micrometers to 45 micrometers), it can ensure a firm bond between the first sub-layer 21 and the cookware substrate, while also providing sufficient oil storage pore size to ensure non-stick performance.

[0065] As an example, the second sublayer 22 is relatively dense, with a thickness ranging from 25 to 45 micrometers. If the second sublayer 22 is too thin, it may not be able to completely cover the surface defects of the first sublayer 21, thus affecting the non-stick performance. If the second sublayer 22 is too thick, the overall thickness will affect the amount of oil filling into the first sublayer 21, thus affecting the long-lasting non-stick performance. In addition, an excessively thick second sublayer 22 will also increase costs and production difficulty. A thickness of 25 to 45 micrometers for the second sublayer 22 not only ensures the filling and release of oil but also effectively covers the first sublayer 21, avoiding surface defects in the coating.

[0066] In some embodiments, the spraying method for forming the first sub-layer 21 is arc spraying, and the spraying method for forming the second sub-layer 22 includes plasma spraying, supersonic spraying, or cold spraying.

[0067] In these embodiments, a first sublayer is first formed by arc-spraying filament, and a second sublayer is formed by plasma spraying, supersonic spraying, or cold spraying particles. By combining different spraying methods, a metal coating layer 20 with a gradient porosity structure 40 is constructed. The metal coating layer 20 with the gradient porosity structure 40 forms the basis of the coating layer 30 with the gradient porous structure 50, thus creating a gradual transition from porous to dense structure from the inside out. In the gradient porous structure 50, especially in the lower layer, a large amount of oily substances can be stored, and these stored oily substances can be continuously and stably released through the pores of the upper layer. This allows a continuously stable oil film to form on the surface of the coating layer 30, possessing low surface energy, thereby satisfying initial non-stick properties. Since the oil film within the gradient porous structure is protected by the coating layer 30, which acts as a framework, it exhibits long-lasting non-stick properties. Furthermore, although the coating layer 30 with the gradient porous structure is a multi-layered composite structure, good bonding between its layers can be achieved through the selection of materials and the distribution of pore sizes.

[0068] In some embodiments, the material forming the first sub-layer 21 is aluminum wire, and the material forming the second sub-layer 22 is aluminum particles. By sequentially spraying the above-mentioned material forms onto the cookware substrate, a metal spray coating 20 with the above-mentioned pore distribution can be formed, which can meet the requirements of serving as an oil storage skeleton for the cookware.

[0069] Specifically, the diameter of the aluminum wire is 1.5 mm to 2.5 mm; the particle size of the aluminum particles is 80 micrometers to 150 micrometers. Such specific forms can form a metal spray coating 20 with a suitable pore distribution.

[0070] In some embodiments, the thickness of the sprayed coating 30 is 30 micrometers to 100 micrometers.

[0071] In these embodiments, within this thickness range, a suitable gradient porous structure 50 can be formed for oil storage while ensuring coating strength, thereby ensuring the non-stick properties of the cookware.

[0072] In some embodiments, the cookware further includes an oily substance filling the gradient porous structure 50, the oily substance including at least one of animal oil, vegetable oil and silicone oil.

[0073] According to a second aspect of this invention, research is conducted on the manufacturing of coating structures for cookware. Different spraying methods (e.g., arc spraying, plasma spraying) and / or the morphology of the bonding materials (filamentous, granular) are employed to form a metal coating layer 20 with a gradient pore structure 40. The layers of the metal coating layer 20 are arranged from the inside out according to a rule of decreasing pore size and decreasing porosity. This allows for effective interconnection between the layers, facilitating the distribution of oily substances throughout the coating layer 20 and achieving a larger storage capacity. This allows for continuous release during subsequent use, optimizing non-stick properties. Furthermore, the pore distribution between the layers ensures the bonding strength between them.

[0074] Then, the metal spray coating 20 is subjected to hard oxidation and high-temperature calcination. Hard oxidation forms a dense alumina film on the outer surface and inner walls of the pores of the metal spray coating 20, which significantly improves the hardness, wear resistance and corrosion resistance of the coating. High-temperature calcination causes the coating to transform into various crystal morphologies, especially α crystal morphology, which increases the content of α-Al2O3 in the final spray coating, strengthens the coating structure, eliminates internal stress and improves the overall strength and stability of the coating.

[0075] According to a second aspect of the present invention, a method for manufacturing a cookware is provided, wherein the method includes:

[0076] Step S101: Provide the cookware base 10.

[0077] Step S102: A metal spray coating 20 with a gradient pore structure 40 is formed on the cookware substrate 10.

[0078] Step S103: Hard oxidation and sintering are performed on the metal spray coating 20 with gradient porous structure 40 to obtain a spray coating 30 with gradient porous structure 50 that has been oxidized and sintered.

[0079] According to this invention, the oxidized and sintered coating layer 30 has high hardness, making the gradient porous structure's framework more wear-resistant and robust, thus ensuring the long-term effectiveness of the gradient porous structure. During use, the cookware can effectively store oily substances within the gradient porous structure, forming a uniform oil film with excellent non-stick properties over long-term use. Furthermore, the entire manufacturing process does not involve atomization spraying, eliminating the environmental pollution problems introduced by atomization spraying.

[0080] The following describes a method for manufacturing a cooker according to the present invention with reference to specific embodiments.

[0081] Provide cookware base

[0082] According to this invention, the cookware substrate has a basic structure of a cookware formed by stretching a corresponding base material. In some embodiments, the thickness of the cookware substrate is 1.55mm-2.5mm, which ensures the overall strength of the final cookware.

[0083] In some embodiments, the inner surface of the cookware substrate has a rough structure of 3μm-6μm. As an example, the inner surface of the cookware substrate is treated with mirror blasting, sandblasting, or etching to create a rough structure with a surface roughness of 3μm-6μm. This roughness enhances the adhesion between the cookware substrate and the first sublayer, further improving the durable non-stick properties.

[0084] In some embodiments, the cookware substrate includes one of an iron substrate, a cast iron substrate, an aluminum substrate, a titanium substrate, a stainless steel substrate, and a low-carbon steel substrate. It should be noted that the iron substrate, aluminum substrate, and titanium substrate are substrates made of iron, aluminum, titanium, or their corresponding alloys.

[0085] According to this utility model, the method for manufacturing cookware can be adapted to a wider variety of substrate types, thereby expanding the range of substrates that cookware manufacturing can adapt to, and thus has good versatility.

[0086] Forming a metal spray coating 20

[0087] According to this invention, different pores are constructed by using different spraying methods and / or materials of different forms, thereby constructing a metal spray coating 20 with a gradient pore structure 40 by multiple sub-layers.

[0088] In some embodiments, the multiple sublayers include a first sublayer and a second sublayer. Different pore sizes are constructed using different spraying methods and / or materials of different morphologies, including: arc spraying of filaments to form the first sublayer on the cookware substrate; plasma spraying, supersonic spraying, or cold spraying of particles to form the second sublayer. The first sublayer serves as the bottom layer of the metal spray coating 20, and the second sublayer serves as the top layer of the metal spray coating 20. It should be noted that arc spraying of filaments can form a first sublayer with high porosity and large pore size, while plasma spraying, supersonic spraying, or cold spraying of particles can form a second sublayer with low porosity and small pore size. Thus, the gradient pore structure 40 of this invention can be constructed.

[0089] According to this invention, aluminum wire is electro-sprayed to form a first sub-layer on a cookware substrate. Specifically, aluminum wire is deposited onto the cookware substrate using electro-spraying to form the first sub-layer. Electro-spraying melts the metal wire at high temperature and uses a high-speed airflow to spray the molten metal particles onto the surface of the cookware substrate, thereby forming a first sub-layer that is firmly bonded to the surface of the cookware substrate.

[0090] Specifically, the parameters for arc spraying include a voltage of 30V-35V, a current of 200A-300A, a spraying pressure of 0.4MPa-0.5MPa, a wire feed speed of 0.8m / min-1.0m / min, a spraying distance of 20cm-30cm, and a spray gun angle of 60°-70°. Arc spraying is highly efficient, capable of forming a first sublayer with large and numerous pores (porosity of 10%-20%, pore size of 40 to 50 micrometers) while ensuring the bonding force between the first sublayer and the cookware substrate.

[0091] In these embodiments, the first sublayer serves as the bottom layer of the metal spray coating 20 and is used to form the main structural part for oil storage, so as to ensure the amount of oil stored in the gradient pore structure 40 of the metal spray coating 20. On the other hand, the first sublayer serves as the bottom layer of the metal spray coating 20 and is combined with the cookware substrate, which can provide a stable base for the subsequent metal spray coating 20.

[0092] According to this invention, after forming the first sublayer, plasma spraying, supersonic spraying, or cold spraying particles are applied to form the second sublayer. Specifically, aluminum particles are applied by plasma spraying, supersonic spraying, or cold spraying to deposit material on the first sublayer to form the second sublayer.

[0093] As an example, plasma spraying utilizes high-temperature, high-energy plasma jets to heat particles to a molten or semi-molten state and spray them at high speed onto a substrate to form a relatively uniform and dense plasma layer (porosity of 5%-10%, pore size of 10 to 20 micrometers) as a second sublayer. Plasma spraying can generate temperatures reaching tens of thousands of degrees Celsius, allowing it to spray almost all types of particles, including materials with high melting points and high hardness. Simultaneously, the high energy and high-speed spraying of the plasma jet create a strong mechanical and chemical bond between the second sublayer and the substrate, improving the adhesion of the second sublayer.

[0094] As an example, the protective gas for plasma spraying is nitrogen, and the parameters for plasma spraying include a voltage of 30V-40V, a current of 300A-400A, a powder feed rate of 1.0g / s-2.0g / s, a spraying speed of 1.0mm / s-2.0mm / s, and a spraying angle of 65°-75°.

[0095] As an example, supersonic spraying specifically refers to supersonic flame spraying, wherein the parameters of supersonic flame spraying include a voltage of 60V-70V, a current of 500-600A, a powder feed rate of 1.5g / s-2.5g / s, a spraying speed of 1.0mm / s-2.0mm / s, and a spraying angle of 65°-75°.

[0096] As an example, cold spraying specifically refers to high-pressure cold spraying. The parameters of high-pressure cold spraying include a temperature of 200℃-300℃, a spraying pressure of 3MPa-4MPa, an airflow velocity of 700m / s-800m / s, a powder feed rate of 2.0g / s-2.5g / s, and a spraying angle of 80°-90°.

[0097] In these embodiments, the second sublayer serves as the outer layer of the metal spray coating 20, which forms the basis of the spray coating 30 of the cookware. The above-described method can form a dense sublayer, allowing oily substances to enter under a preset pressure interference and enabling the oily substances to overflow outward at a predetermined speed under the action of temperature to form an oil film, thereby improving the non-stick properties of the spray coating 30.

[0098] In some embodiments, the material forming the first sublayer 21 is aluminum wire with a diameter of 1.5 mm to 2.5 mm; and / or, the material forming the second sublayer 22 is aluminum particles with a particle size of 80 micrometers to 150 micrometers. Here, the aluminum can be selected from the 3003 series.

[0099] In these embodiments, by sequentially spraying the above-described material combination onto the cookware substrate, a metal spray coating 20 with the above-described pore distribution can be formed, which can meet the requirements of serving as an oil storage skeleton for the cookware.

[0100] According to this utility model, when the cookware substrate is an aluminum substrate, thermal spraying is performed using aluminum with a similar composition to the aluminum substrate (such as 3003 aluminum) to form a metal spray coating 20 with a pore gradient. The film layer has a uniform composition, and aluminum has good plasticity, which will have a strong bonding force with the aluminum substrate that serves as the cookware substrate. Furthermore, it is consistent with the material of the cookware substrate, unlike other metal powder (wire) spraying, which has problems such as potential difference corrosion.

[0101] According to this invention, compared with traditional cookware products that have undergone hard oxidation after shot blasting (sandblasting) or have not undergone oxidation, this metal spray coating with pore gradient exhibits better performance after oxidation and high-temperature calcination, such as pore gradient. At the same time, this technology also avoids the problems of insufficient coating performance caused by not undergoing oxidation or high-temperature calcination, such as insufficient hardness, poor corrosion resistance and wear resistance.

[0102] Surface sanding

[0103] According to this utility model, the surface of the metal spray coating 20 is sanded with a 300-mesh scouring pad to achieve a surface roughness of 2-6 micrometers.

[0104] Hard anodizing

[0105] According to this invention, the metal coating 20, through hard oxidation, can improve corrosion resistance and wear resistance to a certain extent. As an example, hard oxidation specifically refers to sulfuric acid anodizing. The specific steps of sulfuric acid anodizing the metal coating 20 include: using a cookware substrate with the metal coating 20 as the anode and a lead plate, etc., as the cathode, immersing it entirely in a sulfuric acid electrolyte. The sulfuric acid electrolyte is a mixture of sulfuric acid and deionized water, with a mass concentration of 10%-20%. This concentration range ensures the smooth progress of the oxidation process while avoiding excessive corrosion due to excessive concentration or poor oxidation effect due to excessively low concentration. After power is connected, the electrolyte temperature is controlled between -5℃ and 10℃. The lower temperature helps slow down the oxidation reaction rate, making the oxide film denser and more uniform. The anolyte current density is 2.5 A / dm³. 2 -5A / dm 2 This current density range ensures a moderate oxide film formation rate while avoiding overheating due to excessive current or insufficient oxidation due to insufficient current. The voltage in the tank is between 50V and 70V; an appropriate voltage helps form a uniform and dense oxide film. The oxidation time is generally 30-40 minutes, within which the oxide film can grow sufficiently to achieve the desired thickness and performance.

[0106] In these embodiments, hard oxidation enables the formation of an amorphous oxide film with a thickness of 25-60 micrometers on the outer surface of the metal spray coating 20.

[0107] High-temperature calcination

[0108] The metal coating first undergoes a hard anodizing process, forming an amorphous oxide film in a sulfuric acid electrolyte. However, this film has a relatively low hardness, typically between 350 HV and 450 HV, which is insufficient to meet the wear and corrosion resistance requirements of cookware during long-term use.

[0109] According to this invention, in order to improve the hardness of the oxide film, a high-temperature calcination step is required after hard oxidation to transform the amorphous oxide film into an α-crystalline morphology, resulting in a cookware with a coating 30 having at least an α-crystalline oxide film 31 on its surface. Specifically, the high-temperature calcination step is performed using a high-temperature acetylene flame or plasma flame as the heat source, with a flame distance of 10cm-15cm to ensure that heat can be uniformly and effectively transferred to the oxide film.

[0110] During the calcination process, the temperature was set at 550℃-600℃, which is a suitable temperature range that can promote the transformation of amorphous alumina into α-crystal morphology while avoiding over-calcination that would degrade the coating performance. The scanning speed (i.e., the speed at which the heat source moves on the coating) was controlled between 5s / dm² and 8s / dm² to ensure that the coating is heated uniformly and achieves the expected calcination effect.

[0111] After high-temperature calcination, the hardness of the oxide film is significantly improved, reaching a range of 650HV-850HV. This improvement not only meets the wear resistance requirements of cookware in daily use but also enhances its corrosion resistance.

[0112] Fill the gradient porous structure of the sprayed coating with oil-based substances.

[0113] According to this invention, the method for manufacturing a cookware further includes filling an oily substance into a gradient porous structure. This allows for the sealing of the gradient porous structure and the achievement of a certain oil storage capacity.

[0114] In some embodiments, oily substances can be filled into the gradient porous structure of the coating layer 30 through vacuum impregnation. Vacuum impregnation allows the oily substances to completely penetrate the gradient porous structure, significantly improving the film's density and corrosion resistance. Furthermore, the oily substances are continuously released during subsequent use to enhance the non-stick effect. Additionally, the oily substances filling the gradient porous structure of the coating layer 30 seal the pores, ensuring the corrosion resistance of the cookware with this coating layer 30. Specifically, the cookware with the gradient porous structure of the coating layer 30 is placed in a high-pressure sealed container, allowing the impregnation liquid to completely cover the surface of the coating layer 30. The high-pressure sealed container is then closed, and vacuum impregnation is performed. Specific parameters include a vacuum degree of 90 Pa-110 Pa; an impregnation pressure of 0.4 MPa-0.7 MPa; an impregnation time of 15 min-30 min; an impregnation temperature of room temperature; and a spin-drying speed of 180 rpm-220 rpm.

[0115] In other embodiments, the cookware substrate is heated, and oily substances are placed in the heated cookware substrate, thereby allowing them to penetrate into the gradient porous structure of the coating layer 30. Specifically, the pot body is preheated to 50°C-70°C, a certain amount of animal oil is poured in and allowed to completely melt, and the oil is evenly spread on the surface of the workpiece with oil-absorbing paper. Natural cooling yields a cookware with a coating layer 30 filled with animal oil in its gradient porous structure.

[0116] According to this utility model, oily substances include animal oils, vegetable oils, silicone oils, and polysiloxanes.

[0117] In some embodiments, the animal oil is a solid-liquid convertible animal oil. For example, the solid-liquid convertible animal oil has a freezing point between 15°C and 48°C. Examples include lard, tallow, and horse fat. During use, at relatively low temperatures, these oily substances can solidify and remain stably within the gradient porous structure, thus acting as a dual lubricant at low temperatures and a liquid lubricant at high temperatures. This reduces the rate of film wear and extends product lifespan.

[0118] In some embodiments, a gradient porous structure of the spray coating 30 filled with vegetable oil may be adopted, wherein the vegetable oil is rapeseed oil, peanut oil or palm oil.

[0119] In some embodiments, the silicone oil may be selected from at least one of methyl silicone oil, dimethyl silicone oil, hydroxyl silicone oil, hydrogen-containing silicone oil, and polyether-modified silicone oil. These silicone oils have specific viscosities and surface tensions, making them more readily absorbed into gradient porous structures. The silicone oil is adsorbed into the gradient porous structure. Furthermore, by weight percentage, the silicone oil comprises 20%-30% low molecular weight silicone oil, 40%-60% medium molecular weight silicone oil, and 20%-30% high molecular weight silicone oil, wherein the low molecular weight silicone oil has a molecular weight between 500 and 1000, the medium molecular weight silicone oil has a molecular weight between 3000 and 6000, and the high molecular weight silicone oil has a molecular weight between 12000 and 30000.

[0120] After selecting a suitable silicone oil, a cookware substrate with a gradient porous structure is impregnated with the silicone oil, thereby obtaining a cookware in which the silicone oil is bonded to the gradient porous structure. As an example, the silicone oil impregnation time for the spray coating can be 2-3 minutes, and the temperature can be 80℃-100℃.

[0121] In these embodiments, high molecular weight silicone oils bond more firmly to the gradient porous structure and release at a slower rate, while low molecular weight silicone oils exhibit better mobility, resulting in better non-stick properties. Medium molecular weight silicone oils balance both mobility and strong bonding. Therefore, by combining low, medium, and high molecular weight silicone oils, on the one hand, the amount of silicone oil entering the gradient porous structure is further increased, ensuring sufficient oil supply; on the other hand, silicone oils with different bonding strengths can be continuously released at various stages of use to achieve a better non-stick effect.

[0122] According to this invention, the oil-based material filling rate in the gradient porous structure is 72-88%. Specifically, the oil-based material filling rate in the pore size of the first sub-layer is 95-100%, the oil-based material filling rate in the pore size of the second sub-layer is 70-95%, and the oil-based material filling rate in the pore size of the third sub-layer is 50-70%.

[0123] After coating, the cookware filled with oil can be placed in a drying oven to dry and cure. The curing temperature is 180℃-200℃ and the curing time is 1min-2min.

[0124] According to this utility model, by using aluminum or aluminum alloy combined with thermal spraying (or cold spraying), hard anodizing, high-temperature calcination and vacuum impregnation of oxide film as means, a coating for cookware that is wear-resistant, corrosion-resistant and has a certain degree of food non-stickiness can be achieved.

[0125] While the embodiments of the present invention have been described in detail above, those skilled in the art can make various modifications and variations to the embodiments of the present invention without departing from the spirit and scope thereof. However, it should be understood that, in the view of those skilled in the art, these modifications and variations will still fall within the spirit and scope of the embodiments of the present invention as defined in the claims.

Claims

1. A cooking utensil, characterized in that, The cookware includes a cookware substrate (10) and a coating layer (30). The coating layer (30) is a metal layer with an oxide film. The coating layer (30) includes an inner layer and an outer layer stacked in the thickness direction of the cookware. The inner layer is disposed on the cookware substrate (10), and the outer layer is disposed on the inner layer. The porosity of the inner layer is greater than that of the outer layer, and the pore size of the inner layer is greater than that of the outer layer. Thus, the inner layer and the outer layer form a coating layer (30) with a gradient porous structure (50).

2. The cookware according to claim 1, characterized in that, The oxide film is located on the outer surface of the metal layer and on the inner walls of the pores of the metal layer; and / or, The oxide film (31) is formed by a high-temperature phase transition of an amorphous oxide film; and / or, The oxide films on the inner walls of the individual pores of the metal layer have gaps to form the gradient porous structure (50); and / or, The metal layer is an aluminum layer, a magnesium layer, or an iron layer, and the oxide film is the corresponding metal oxide film.

3. The cookware according to claim 1, characterized in that, The oxide film (31) is an aluminum oxide thin film, having various crystal morphologies, and including at least an α-crystal morphology; and / or, The oxide film (31) located on the outer surface of the metal layer has a thickness of 25 micrometers to 60 micrometers; and / or, The hardness of the oxide film (31) is 600HV-800HV.

4. The cookware according to claim 1, characterized in that, The sprayed coating (30) is obtained by calcining a metal sprayed coating (20) with a gradient pore structure (40) after anodic hard oxidation at a temperature of 550℃-600℃.

5. The cookware according to claim 4, characterized in that, The metal spray coating (20) with a gradient pore structure (40) includes a first sublayer (21) and a second sublayer (22). The first sublayer (21) is formed as the inner layer of the metal layer, and the second sublayer (22) is formed as the outer layer of the metal layer. The porosity of the first sublayer (21) is greater than that of the second sublayer (22), and the pore size of the first sublayer (21) is greater than that of the second sublayer (22). Thus, the first sublayer (21) and the second sublayer (22) construct a metal spray coating (20) with a gradient pore structure (40).

6. The cookware according to claim 5, characterized in that, The first sublayer (21) has a porosity of 10%-20% and a pore size in the range of 40 micrometers to 50 micrometers; and / or the second sublayer (22) has a porosity of 5%-10% and a pore size in the range of 10 micrometers to 20 micrometers.

7. The cookware according to claim 6, characterized in that, The spraying method for forming the first sub-layer (21) is arc spraying, and the spraying method for forming the second sub-layer (22) includes plasma spraying, supersonic spraying or cold spraying.

8. The cookware according to claim 6, characterized in that, The material forming the first sublayer (21) is aluminum wire, and the material forming the second sublayer (22) is aluminum particles.

9. The cookware according to claim 8, characterized in that, The diameter of the aluminum wire is 1.5 mm to 2.5 mm, and the particle size of the aluminum particles is 80 micrometers to 150 micrometers.

10. The cookware according to claim 1, characterized in that, The thickness of the sprayed coating (30) is 30 micrometers to 100 micrometers.

11. The cookware according to any one of claims 1 to 10, characterized in that, The cookware also includes an oily substance filling the gradient porous structure (50).

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