Composite coating based on medium-temperature alpha-Al2O3 and preparation method thereof

Abstract

The invention relates to the technical field of composite coating preparation, and discloses a composite coating based on medium temperature and a preparation method thereof.The method comprises the following steps that a TiN layer, a TiCN layer, a bonding layer and a layer are sequentially deposited on the surface of a base body at the temperature of 700-900 DEG C through a hot wall type chemical vapor deposition method; the bonding layer comprises a TiCNO layer, a TiAlCNO layer and an oxidation treatment layer which are formed in sequence; the layer is deposited using a mixed gas comprising HCl, and the volume fraction of each gas is 5-10 vol%, 0-3 vol% HCl, 0.3-2.5 vol%, 0.5-1 vol%, the remainder being 5-10 vol%, 0-3 vol% HCl, 0.3-2.5 vol% HCl, and 0.5-1 vol% HCl; all layers in the deposition process are carried out in the temperature range, and the temperature is kept constant. According to the method, the TiCN < + >-based composite coating with excellent binding force can be prepared under the medium temperature condition of 700-900 DEG C; and the application range is wide.

Description

Technical Field

[0001] This invention relates to the field of composite coating preparation technology, specifically to a method based on medium temperature... Composite coatings and their preparation methods. Background Technology

[0002] TiCN+ prepared by hot-wall chemical vapor deposition (CVD) Composite coatings, possessing excellent wear resistance and high-temperature resistance, have been widely used in the field of cemented carbide CNC cutting tools. However, The coating preparation temperature is relatively high, typically between 900-1050 degrees Celsius (the high-temperature reaction zone). However, at this temperature, heat-sensitive materials such as molybdenum and special alloy steel will undergo annealing, leading to a decrease in workpiece hardness and deformation of thin-sheet products. This severely affects workpiece performance and precision, limiting the application of TiCN+ coatings. Composite coatings are used in a wider range of fields. This temperature bottleneck prevents the advantages of hot-wall CVD technology, such as large furnace loading, good coating uniformity, and applicability to complex shapes and large aspect ratio pipes, from being fully utilized in a wider range of industrial scenarios. It also hinders the application and promotion of this coating technology in high-end fields such as aerospace, energy, and precision molds.

[0003] Domestic and international research on TiCN+ Most research on composite coatings focuses on the field of cemented carbide cutting tools, mainly because WC-based cemented carbide has relatively low temperature sensitivity. At 1000℃, even if the deposition time exceeds 24 hours, the WC alloy will not anneal or deform, thus not affecting the final CNC tool performance. , , , The reaction gases can react efficiently and completely, and by adjusting the gas ratio, high-quality products with different structures can be prepared. Coatings. For example, patent CN118880276A describes the preparation of (001) textured coatings within a temperature range of 950-1050 degrees Celsius by adjusting the gas ratio. Composite coating; patent publication number CN105506580A, by adding Gas, Zr modified with (300) texture prepared in the range of 980-1020 degrees. Coating; Patent CN104085142B describes the preparation of textured fine particles within a temperature range of 900-1020 degrees Celsius by adjusting the gas ratio. Coating; US patent US11471951B2, fine particles with (001) texture were prepared at 1000 degrees by controlling HCl flow rate Coating; US patent US2018 / 0002817A1, prepared at 1000 degrees by controlling atmosphere Composite coating; European patent EP2902528B1 prepared (110), (012), (001) different textures at 930-1030 temperature range by controlling gas ratio Composite coating. Among them, (001), (110), (012) and the like are crystal plane indices, used to identify the direction of different atomic planes in the crystal.

[0004] However, once the deposition temperature is reduced to the medium temperature range such as 850℃, if the gas ratio and process parameters at high temperature are still used, the coating adhesion will be significantly reduced, the gas reaction will be incomplete, the deposition rate will be too low, and the nozzle will be easily blocked, which seriously affects the process stability and coating usability, cannot meet the industrial use requirements, and causes great hidden dangers to product quality and fixture maintenance.

[0005] Deposition in the medium temperature range (700-900℃) Coating exploration has been studied abroad, for example: US patent US6689450B2 prepared and Composite coating; Larsson and Ruppi (Microstructure and properties of CVD coatings. International journal of Refractory metals and hard materials, 19 (2001) 515-522) studied the properties of coating prepared at 800 degrees, but the results generally showed that the coating adhesion was poor.

[0006] In these foreign studies, the coating prepared at medium temperature has two main problems, first, the coating adhesion prepared at medium temperature is not ideal, which is difficult to meet the industrial application requirements; second, and are metastable phases, which will irreversibly change to when the service temperature exceeds 600 degrees, accompanied by a certain volume change, which makes the coating wear rapidly during use.

[0007] Currently, domestic research focuses on the preparation of materials using hot-wall CVD technology in the intermediate temperature range. Research on coatings is still in its infancy, but in fields such as molybdenum parts and high-temperature alloy steel parts, there is a market demand for coatings that combine high bonding strength and high-temperature stability. The demand for coatings is becoming increasingly urgent and has become a real need. Therefore, the development of high-adhesion, stable α-phase hot-wall CVD coatings under intermediate temperature conditions is crucial. Composite coatings and their preparation methods are of great significance. Summary of the Invention

[0008] This invention aims to provide a medium-temperature-based The composite coating and its preparation method can prepare TiCN+ with excellent adhesion under medium temperature conditions of 700-900 degrees Celsius. Base composite coating; with a wide range of applications.

[0009] To achieve the above objectives, the present invention provides the following basic solution.

[0010] Option 1 A medium temperature-based The method for preparing the composite coating includes the following steps: A hot-wall chemical vapor deposition method was used to sequentially deposit TiN, TiCN, and a bonding layer on the substrate surface at a temperature of 700–900℃. layer; The bonding layer comprises a TiCNO layer, a TiAlCNO layer, and an oxidation treatment layer formed sequentially; The Layers use contain HCl , and The mixture of gases was deposited, with each gas having a volume fraction of 5–10 vol%. ,0–3 vol%HCl, 0.3–2.5 vol% 0.5-1 vol% The margin is ; All layers are deposited within the temperature range during the deposition process, and the temperature remains constant.

[0011] Option 2 A medium temperature-based The composite coating, deposited on a substrate, comprises, from the inside out: a TiN layer bonded to the substrate; a TiCN layer deposited on the TiN layer; a bonding layer deposited on the TiCN layer; and a [missing information - likely a coating material] deposited on the bonding layer. layer; The bonding layer is a composite structure of TiCNO, TiAlCNO, and an oxide-treated layer formed by CVD. The layer is pure The phase structure, and the composite coating is prepared by hot-wall chemical vapor deposition in a temperature range of 700°C to 900°C.

[0012] The working principle and advantages of this invention are as follows: This invention provides a medium-temperature-based The composite coating and its preparation method can prepare TiCN+ with excellent adhesion under medium temperature conditions of 700-900 degrees Celsius. Base composite coating; wide range of applications. Key points: This solution significantly reduces the deposition temperature by optimizing the gas combination and ratio, and designing a multi-layer transition structure. This avoids the hardness reduction and deformation problems caused by high-temperature annealing of the substrate, while maintaining a high bonding force between the coating and the substrate. This not only helps to broaden the application range of this type of coating, but also helps to give full play to the advantages of hot-wall CVD technology in handling complex-shaped workpieces and large furnace loading capacity, providing a feasible surface strengthening solution for high-precision, thin-walled parts.

[0013] Notably, this scheme achieves pure [propagation] under mesophilic conditions. Mutually Stable preparation of coatings, effectively avoiding metastable phases (such as...) phase or The formation of the phase. Specifically, in known existing technologies, deposition in the intermediate temperature range yields... The coatings are mostly metastable phases, which will undergo changes in orientation under high-temperature service conditions. Phase transformation, accompanied by volume shrinkage and internal stress release, leads to coating cracking and peeling. This solution addresses this by addressing the bonding layer, oxide layer, and... Precise control during the layer deposition stage , CO , The proportion of reacting gases such as HCl promotes Phase nucleation and growth were inhibited, suppressing the formation of metastable phases. Furthermore, a specially designed TiCNO / TiAlCNO composite structure served as a transition layer, gradually harmonizing the formation of TiCN and... The differences in lattice structure and thermal expansion between the layers further ensure the overall stability and bonding strength of the coating system.

[0014] Furthermore, from the perspective of process efficiency and engineering applications, by adjusting... The reaction gas ratio of the layer can also be guaranteed under medium temperature conditions. The growth speed of the composite coating is not less than 0.6 μm / h, which overcomes the technical bottlenecks of slow growth, incomplete reaction and easy plugging in the process of medium-temperature CVD, and meets the requirements of industrial rapid production. Meanwhile, the whole coating deposition process can be completed at the same temperature, without temperature adjustment due to different coating stages, which not only simplifies the equipment control and process flow, improves the process stability, but also helps to reduce energy consumption; and is not only suitable for traditional hard alloy cutters, but also can be extended to high-temperature sensitive materials such as molybdenum and special alloy steel. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 The application is a kind of composite coating based on medium-temperature and a preparation method thereof. Figure 2 The application is a kind of composite coating based on medium-temperature Figure 3 The application is a kind of composite coating based on medium-temperature Figure 4 The application is a kind of composite coating based on medium-temperature Figure 5 The application is a kind of composite coating based on medium-temperature Figure 6 The application is a kind of composite coating based on medium-temperature Figure 7 The application is a kind of composite coating based on medium-temperature Figure 8 The application is a kind of composite coating based on medium-temperature Figure 9 The application is a kind of composite coating based on medium-temperature Figure 10 The application is a kind of composite coating based on medium-temperature

[0016] The marks in the drawings of the specification include: 1-composite coating, 00-substrate, 11-TiN, 12-TiCN, 13-bonding layer, 14- , 131-TiCNO, 132-TiAlCNO, 133-oxidation treatment layer. DETAILED DESCRIPTION

[0017] The following will be further described in detail through specific embodiments: The application is a kind of composite coating based on medium-temperature Figure 1 The application is a kind of composite coating based on medium-temperature The preparation method comprises the following steps: A hot-wall chemical vapor deposition method was used to sequentially deposit TiN, TiCN, and a bonding layer on the substrate surface at a temperature of 700–900℃. layer; The outermost layer is the first layer. All layers are deposited within the stated temperature range, and the temperature remains constant.

[0018] Optionally, the deposition temperature is preferably 800–900°C.

[0019] The substrate is hard alloy or special alloy steel.

[0020] The TiN layer is used to ensure the adhesion between the coating and the substrate, and the coating thickness is 0.3-1.5 μm; its deposition pressure is 100-500 mbar, and it uses a solution containing 0.5-3 vol%. 25–40 vol% The margin is A mixture of gases is used for vapor phase deposition.

[0021] The TiCN layer serves as a wear-resistant layer, with a coating thickness of 1-10 μm; its deposition pressure is 100–300 mbar, and it uses materials containing 2–3.5 vol%. 1–2 vol% 30–40 vol% The margin is A mixture of gases is used for vapor phase deposition.

[0022] In TiCN layer deposition, compared to conventional TiCN deposition processes, the deposition pressure is typically limited to a lower range of 50-100 mbar to reduce coating grain size. However, at temperatures below 800 degrees Celsius, the gas reaction rate decreases. To improve deposition efficiency and economy, the deposition pressure needs to be increased, ideally exceeding 200 mbar. This approach, by increasing the reaction pressure, effectively promotes the mixing and mass transfer of reactant gases. While ensuring refined coating grain size, it also considers deposition efficiency and process economy, achieving a better balance between coating performance and preparation cost.

[0023] The bonding layer is used to ensure that TiCN and To ensure effective bonding, given the different structures of the two materials, the bonding layer was designed using a three-step process: "TiCNO + TiAlCNO + oxidation treatment," allowing TiCN to gradually transition to its final form. This ensures adhesion, and the coating thickness is 0.3-1μm.

[0024] Specifically, the bonding layer comprises a TiCNO layer, a TiAlCNO layer, and an oxidation treatment layer formed sequentially.

[0025] The TiCNO layer was deposited at a pressure of 300–500 mbar, using a solution containing 2–4 vol%. 7–13 vol% 7–13 vol% 2–4 vol% CO, balance: A mixture of gases is used for vapor phase deposition.

[0026] The TiAlCNO layer was deposited at a pressure of 100–300 mbar, using a solution containing 2–5 vol%. 5–10 vol% 5–10 vol% , 2–5.5 vol%CO, 0.5-1.5 vol% The margin is A mixture of gases is used for vapor phase deposition.

[0027] By employing the unique TiCN+TiCNO+TiAlCNO multi-process progressive mode and implementing precise synergistic control of gas ratios (especially CO) and deposition pressure, it helps to solve the problem of simultaneously ensuring the required parameters under intermediate-temperature chemical vapor deposition conditions. The core challenges of heteroepitaxial growth and excellent interfacial bonding.

[0028] Specifically, relevant studies have demonstrated that this formation can only occur on oxidized TiN, TiC, or TiCN surfaces. To ensure good adhesion, the bonding layer is designed as a multi-process mode of TiCN+TiCNO+TiAlCNO. The proportion of oxygen is crucial; after oxidation, a layer of Ti oxide forms on the surface of TiN, TiC, or TiCN. Epitaxial growth on it, insufficient or excessive oxygen may cause Unable to form Phase or other factors can affect the bonding strength. Under intermediate temperature conditions, the reactivity of reactive gases decreases, especially the oxidizing ability of oxidizing gases. Therefore, under intermediate temperature conditions, in order to obtain good bonding strength, the proportion of various gases in the bonding layer needs to be precisely controlled, especially the proportion of CO, to ensure sufficient oxidation of TiCN. At the same time, in order to improve the deposition rate under intermediate temperature conditions, the deposition pressure design also needs to be higher than that of conventional high temperature processes.

[0029] This method, through precise control of the proportions of gases such as CO, ensures that the TiCN substrate receives sufficient and appropriate oxidation, thus providing... The epitaxial growth creates an ideal chemical interface; at the same time, by appropriately increasing the deposition pressure, the reaction kinetic limitations under the medium temperature environment are effectively compensated, ensuring processing efficiency.

[0030] The deposition pressure of the oxidation treatment layer is 50-150 mbar, using a mixed gas containing 1-5 vol% , 0.5-3 vol% CO, 1-3 vol% HCl, and the balance .

[0031] The layer is a surface layer, has excellent high-temperature resistance and wear resistance, and is a pure phase. The layer is deposited using a mixed gas containing , HCl, , and , and the volume fraction of each gas is: 5-10 vol% , 0-3 vol% HCl, 0.3-2.5 vol% , 0.5-1 vol% , and the balance . The deposition pressure is 100-300 mbar, and the growth rate .

[0032] Under medium-temperature conditions, the gas reactivity decreases, and if the deposition of the coating is carried out according to the conventional high-temperature process, even if a large proportion of catalyst is used, it is still possible that the and reactions are not fully carried out, and white blocky substances are generated to block the gas outlet holes. Therefore, in order to ensure that the reactions are fully carried out, the present scheme is carried out in a large proportion under medium-temperature conditions during the deposition process, and the / ratio is usually greater than 5, which is much greater than the level of 1.5-3 under high-temperature conditions. At the same time, a high proportion of catalyst is used, and the deposition pressure is higher than 100 mbar, preferably higher than 200 mbar, which is also greater than the level of 60-80 mbar under high-temperature conditions. Through the synergistic effect of these measures, not only is it ensured that the growth process does not cause problems of pore blockage, but it is also ensured that the growth rate is at a high level.

[0033] The embodiment also provides a composite coating based on medium-temperature deposition on a substrate, which uses a kind of medium-temperature ​The preparation method of the composite coating is prepared from inside to outside, including: a TiN layer combined with the substrate; a TiCN layer deposited on the TiN layer; a combined layer deposited on the TiCN layer, a layer deposited on the combined layer The combined layer is a composite structure of TiCNO, TiAlCNO and oxidation treatment layer formed by CVD method; the layer is a pure phase structure, and the composite coating is prepared by hot-wall chemical vapor deposition at a temperature range of 700-900℃.

[0034] To verify the effectiveness and superiority of the scheme, the following specific application examples are combined with multiple test comparisons for illustration.

[0035] WC-8% cemented carbide and special alloy steel (sheet, size 30mm*70mm*0.7mm) are selected as the substrate, wherein the edge of the cemented carbide is passivated with a passivation value of 35μm, and both substrates are sandblasted and cleaned before coating to ensure the cleanliness of the substrate surface and are placed in the furnace for coating at the same time.

[0036] SCT-600TH hot-wall CVD coating furnace is selected for coating.

[0037] The total structure of the coating: from the substrate to the outside, the coating composition along the growth direction of the coating is TiN layer → TiCN layer → combined layer (TiCNO → TiAlCNO → oxidation treatment) → layer.

[0038] Application Example 1 A preparation method of a composite coating based on medium-temperature is applied to perform coating. The specific coating temperature, pressure, gas type and ratio, etc. parameters are shown in Table 1. The deposition temperature is kept constant at 850℃ throughout the process.

[0039] Table 1 Coating growth process parameters of application example 1

[0040] Application Example 2 A preparation method of a composite coating based on medium-temperature is applied to perform coating. The specific coating temperature, pressure, gas type and ratio, etc. parameters are shown in Table 2. The deposition temperature is kept constant at 780℃ throughout the process.

[0041] Table 2 Coating growth process parameters of application example 2

[0042] Coating performance results: Adhesion: The coating adhesion was tested on the surface of WC cemented carbide by scratch testing with a load of 100N. Figure 2 The morphology of the scratch in Application Example 1 is shown under a stereomicroscope. Figure 3 For the acoustic signal and friction coefficient curve of the scratching process in Application Example 1, combined with Figure 2 and Figure 3 The acoustic signal indicates that the coating adhesion is 94N, reaching a high temperature. Equal level of binding force.

[0043] Figure 4 The image shows the morphology of the scratches in Application Example 2 under a stereomicroscope. The coating did not crack during the scratching process, and the adhesion strength reached 100N, achieving high temperature resistance. Equal level of binding force.

[0044] Reaction sufficiency: Visual inspection is performed. In application example 1, a special alloy steel sheet with dimensions of 30mm*70mm*0.7mm, such as... Figure 5 As shown, the appearance and color are uniform, similar to the black material prepared under high temperature conditions. Similar colors, no cause and The white powdery substance formed from incomplete reaction proves that the reaction process was complete at 850℃.

[0045] In application example 2, the cemented carbide cutting tools tested in the furnace, such as Figure 6 As shown, the fixture and blade did not produce any white powdery substance due to insufficient gas reaction, proving that the reaction process was complete at 780℃. The appearance and color were uniform overall, but the color was brownish.

[0046] Deposition rate: The fracture morphology of the coatings in Application Examples 1 and 2 was observed by scanning electron microscopy, the coating thickness was measured, and the deposition rate was calculated. The growth rate, as can be seen from the SEM images, is as follows: In application example 1, for example... Figure 7 As shown, With a thickness of approximately 5.1 μm and a growth rate of approximately 0.85 μm / h (greater than 0.6 μm / h), it meets the requirements for rapid industrial production.

[0047] In application example 2, such as Figure 8 As shown, With a thickness of approximately 5.2 μm and a growth rate of approximately 0.74 μm / h (greater than 0.6 μm / h), it also meets the requirements for rapid industrial production.

[0048] Phase structure analysis: Determined by XRD patterns The structure, through data comparison, XRD pattern shows that the coating diffraction peaks in the coating correspond to Figure 9 and Figure 10 the standard card (PDF-46-1212), as shown, it is proved that the pure phase structure is obtained under the conditions of 850 ° and 780 °.

[0049] The embodiment provides a kind of based on medium-temperature Composite coating and its preparation method, TiCN Based composite coating with excellent bonding force can be prepared under the condition of medium temperature of 700-900 degrees;Wide application range.

[0050] Specifically, first, the present scheme designs a multi-layer transition structure including TiN, TiCN and composite bonding layer composed of TiCNO, TiAlCNO and oxidation treatment layer.The structure is not simply stacked, but each layer has a clear function orientation: TiN layer ensures the initial bonding with substrate;TiCN layer provides hardness and toughness as support body;Composite bonding layer cleverly relieves the interface stress between TiCN and due to the huge difference in lattice constant and thermal expansion coefficient through the gradient change of its composition (gradually introducing Al, O elements, reducing C, N elements), so as to provide a more matched substrate in chemical and structure for the deposition of top layer, and provide support for realizing medium-temperature high bonding force.

[0051] Secondly, the present scheme carries out unique construction to the reaction gas system of layer.The combination of this specific gas ( , , HCl, , ) and its concentration window is the conclusion obtained through a large number of experiments, not easily obtained by simple extrapolation or equal proportion scaling from existing high-temperature process or medium-temperature Phase process.

[0052] The above-mentioned are only embodiments of the present application, and the common knowledge of specific structures and characteristics in the scheme is not described in detail, and the ordinary skilled person in the art knows all the ordinary technical knowledge in the technical field of the application before the application date or the priority date, can know all the prior art in the field, and has the ability to apply conventional experimental means before that date, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary skilled person in the art can perfect and implement the present scheme under the guidance of the present application, and the ordinary

Claims

1. A method for the production of a composite coating based on medium temperature comprising the following steps: ​ Deposition of TiN layer, TiCN layer, bonding layer and layer; the bonding layer comprises a TiCN0 layer, a TiAlCN0 layer and an oxidation treatment layer formed in sequence; The layer is deposited using a mixture gas comprising , HCl, , and with each gas volume fraction: 5 - 10 vol% , 0 - 3 vol% HCl, 0.3 - 2.5 vol% , 0.5 - 1 vol% , with the balance being ; all layers during the deposition are performed in the temperature range, and the temperature is kept constant.

2. A method based on medium temperature according to claim 1 The method for preparing the composite coating is characterized in that, The deposition pressure of the TiN layer is 100 - 500 mbar using a mixed gas containing 0.5 - 3 vol% , 25 - 40 vol% , the balance being H2.

3. A method of preparing a composite coating based on medium temperature superconductors according to claim 1, characterized in that The deposition pressure of the TiCN layer is 100 - 300 mbar using a mixed gas comprising 2 - 3.5 vol% , 1 - 2 vol% , 30 - 40 vol% , the remainder being H2.

4. A method of preparing a composite coating based on medium temperature superconductors according to claim 1, characterized in that, The deposition pressure of the TiCNO layer is 300 - 500 mbar using a gas mixture comprising 2 - 4 vol% , 7 - 13 vol% , 7 - 13 vol% , 2 - 4 vol% CO, the remainder being H2. ​ 5. A method of preparing a composite coating based on medium temperature superconductors according to claim 1, characterized in that, The deposition pressure of the TiAlCNO layer is 100 - 300 mbar using a mixed gas comprising 2 - 5 vol% , 5 - 10 vol% , 5 - 10 vol% , 2 - 5.5 vol% CO, 0.5 - 1.5 vol% , the remainder being H2. ​ 6. A method of preparing a composite coating based on medium temperature superconductors according to claim 1, characterized in that The deposition pressure of the oxidation treatment layer is 50 - 150 mbar using a mixed gas containing 1 - 5 vol% , 0.5 - 3 vol% CO, 1 - 3 vol% HCl, and the balance being H2.

7. A method of preparing a composite coating based on medium temperature superconductors according to claim 1, characterized in that The The deposition pressure of the layer is 100 - 300 mbar, the growth speed .

8. A method of preparing a composite coating based on medium temperature The deposition temperature is preferably 800-900 °C. ​ 9. A method of preparing a composite coating based on medium temperature superconductors according to claim 1, characterized in that The substrate is cemented carbide or special alloy steel.

10. A composite coating based on medium temperature deposited on a substrate, characterized in that comprise, in order from the inside out: a TiN layer bonded to the substrate; a TiCN layer deposited on the TiN layer; a bonding layer deposited on the TiCN layer, a layer deposited on the bonding layer layer; The bonding layer is a composite structure of TiCNO, TiAlCNO and an oxidation treatment layer formed by a CVD method. The bonding layer is a pure phase structure, and the composite coating is prepared by a hot-wall chemical vapor deposition at a temperature range of 700-900°C.

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