CN107881469B - Diamond-like composite coating, preparation method and use thereof, and coating tools - Google Patents

Abstract

The invention provides a diamond-like composite coating, its preparation method and use, and a coating tool, and relates to the technical field of composite coatings. The diamond-like composite coating includes a diamond-like surface coating and a composite transition layer arranged in a layered structure. ; The composite transition layer includes a metal coating, a first metal transition layer, a diamond-like intermediate coating and a second metal transition layer that are alternately arranged in sequence; the first metal transition layer is used to combine with the diamond-like surface coating; the metal coating or The first metal transition layer is used to combine with the metal substrate; along the direction from the metal coating to the diamond-like surface coating, the carbon content in the first metal transition layer gradually increases, and the carbon content in the second metal transition layer gradually decreases, It alleviates the existing technical problems of poor bonding force between the diamond-like layer and the metal substrate and easy falling off, and achieves the purpose of improving the bonding force between the diamond-like layer and the metal base.

Description

Diamond-like composite coating, preparation method and use thereof, and coating tools

Technical field

The present invention relates to the technical field of composite coatings, and in particular to a diamond-like composite coating, its preparation method and use, and coating tools.

Background technique

Diamond-like carbon film is an amorphous carbon film containing a large number of sp3 bonds. It has high hardness, low friction coefficient, good corrosion resistance and stable chemical properties. It is widely used in electromechanical systems, automotive parts, aerospace, Medical devices and many other fields.

The diamond-like film layer usually prepared has large residual stress, poor hardness and toughness, and the large difference in thermal expansion coefficient and low matching between the diamond-like film and the metal substrate results in poor bonding force between the two, easy to fall off, and difficulty in attaching to the surface of the metal substrate. Depositing diamond-like diamonds greatly limits the application of diamond-like films, especially when the substrate is stainless steel. Due to the low matching between stainless steel and diamond-like films and excessive stress, the film can easily fall off.

In view of this, the present invention is specially mentioned.

Contents of the invention

The first object of the present invention is to provide a diamond-like composite coating, and the second object of the present invention is to provide a preparation method of the above-mentioned diamond-like composite coating to alleviate the existing diamond-like layer's large residual stress, poor hardness and toughness. Poor, and the large difference in thermal expansion coefficient and low matching between the diamond-like layer and the metal substrate leads to technical problems such as poor bonding force between the two and easy falling off.

A third object of the present invention is to improve the use of the above-mentioned diamond-like composite coating, which is used in protective coatings of equipment to prevent damage.

The fourth object of the present invention is to provide a coated tool including the above diamond-like composite coating.

In order to achieve the above objects of the present invention, the following technical solutions are adopted:

A diamond-like composite coating, including a diamond-like surface coating and a composite transition layer arranged in a layered structure;

The composite transition layer includes a metal coating, a first metal transition layer, a diamond-like intermediate coating and a second metal transition layer that are alternately arranged in sequence; the first metal transition layer is used to combine with the diamond-like surface coating. ;The metal coating or the first metal transition layer is used to combine with the metal substrate;

Along the direction from the metal coating to the diamond-like surface coating, the carbon content in the first metal transition layer gradually increases, and the carbon content in the second metal transition layer gradually decreases.

Further, the ratio of the thicknesses of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer is (3-4): (1-2): ( 3-4):(1-2).

Further, the sum of the single layer thicknesses of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer is 10 to 200 nm.

Further, the thickness of the composite transition layer is 2-10 μm, preferably 3-9 μm.

A method for preparing the above-mentioned diamond-like composite coating, using a deposition method to alternately prepare a metal coating, a first metal transition layer, a diamond-like intermediate coating and a second metal transition layer, and then obtain a surface layer with a first metal transition layer. After the composite transition layer is composited, a diamond-like surface coating is deposited on the surface of the composite transition layer to obtain a diamond-like composite coating.

Further, a metal coating is first deposited and prepared by magnetron sputtering, and during the process of depositing a metal film on the surface of the obtained metal coating, carbon doping is performed to obtain a first metal transition layer with a gradually increasing carbon content. A diamond-like intermediate coating is prepared by depositing on the surface of the transition layer, and then metal doping is performed in the process of depositing a diamond-like film on the surface of the obtained diamond-like intermediate coating to obtain a second metal transition layer with a gradually decreasing carbon content; and then the metal coating is repeated The preparation process of the layer, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer, finally obtains a composite transition layer with the first metal transition layer as the surface layer, and then deposits a diamond-like surface coating on the surface of the composite transition layer A diamond-like composite coating was obtained.

Further, the preparation method includes the following steps:

Step a) Use the magnetron sputtering method to deposit and prepare the metal coating: the process parameters include: the vacuum chamber pressure is 0.2~1.3Pa, inert gas is introduced, the inert gas flow is 50~400sccm, and the power of the metal target is 1~ 2.4KW, substrate bias voltage -100~-300, obtain metal coating after deposition; deposition time is preferably 5~10min;

Step b): After step a) is completed, turn on the carbon source target and increase the power of the carbon source target from 0KW to 1-2KW within 3-5 minutes. At the same time, increase the power of the metal target from 1-2.4KW within the same time. Reduce to 0KW to obtain the first metal transition layer;

Step c): After step b) is completed, maintain the power of the carbon source target for sputtering deposition for 5 to 10 minutes to obtain a diamond-like intermediate coating;

Step d): After step c) is completed, turn on the metal target and increase the power of the metal target from 0KW to 1-2.4KW within 3-5 minutes. At the same time, reduce the power of the metal target from 1-2KW within the same time. 0KW, obtain the second metal transition layer;

Step e): Repeat the process of steps a) to d) to finally obtain a composite transition layer whose surface layer is the first metal transition layer;

Step f): Preparing a diamond-like surface coating by depositing on the surface of the composite transition layer obtained in step e) by magnetron sputtering. The process parameters include: passing inert gas, the power of the carbon source target is 1 to 2KW, and the substrate bias voltage The substrate bias voltage is -10~-300V, and a diamond-like surface coating is obtained after deposition; the deposition time is preferably 5~10 minutes.

Further, the composite transition layer is deposited on the surface of the metal substrate using a magnetron sputtering method.

Further, the metal substrate is first pretreated, and then the composite transition layer is prepared.

Further, the metal substrate includes a stainless steel substrate, die steel, high speed steel or cemented carbide.

Further, the pretreatment includes the steps of cleaning with cleaning solution, glow cleaning and ion etching cleaning.

Further, the process parameters of the glow cleaning include: introducing inert gas, the inert gas flow rate is 300~500 sccm, the working pressure is 1.0~1.7Pa, and the substrate bias voltage is -500~-800V; optionally, the glow cleaning The cleaning time during cleaning is 10 to 30 minutes.

Further, the process parameters of the ion etching cleaning include: inert gas is introduced, the inert gas flow rate is 70~500 sccm, the ion source voltage is 20~30V, the working pressure is 0.5~1.7Pa, and the substrate bias voltage is -100~-800V. ; Optionally, the cleaning time in the glow cleaning is 10 to 30 minutes.

The use of the above diamond-like composite coating in equipment surface protection.

A coated tool includes a tool body, and the surface of the tool body is combined with the above-mentioned diamond-like composite coating or the diamond-like composite coating prepared by the above preparation method.

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

The diamond-like composite coating provided by the invention includes a diamond-like surface coating and a composite transition layer. The composite transition layer includes a metal coating, a first metal transition layer, a diamond-like intermediate coating and a second metal transition layer that are alternately arranged in sequence. , wherein the first metal transition layer is used to combine with the diamond-like surface coating, and the metal coating or the first metal transition layer is used to combine with the metal substrate.

When the first metal transition layer is combined with the metal substrate, since the lattice matching and stress of the first metal transition layer and the metal substrate are better matched, the bonding force between the first metal transition layer and the metal substrate is higher, thus The bonding force between the composite coating and the metal substrate is increased to prevent the composite coating and the metal substrate from falling off. At the same time, the carbon content in the first metal transition layer on the surface of the composite transition layer exists in a gradient manner, and the gradual increase in carbon content improves the bonding strength between the first metal transition layer and the diamond-like surface coating.

When a metal coating is provided between the first metal transition layer and the metal substrate, and the metal coating is combined with the metal substrate, the carbon content in the metal coating is consistent with the carbon content in the metal substrate, and the matching degree between the two is higher. This can further increase the bonding strength between the composite coating and the metal substrate and prevent the composite coating from falling off the metal substrate.

In addition, in the composite coating of the present invention, the first metal transition layer and the second metal transition layer are combined with the diamond-like intermediate coating, and the first metal transition layer is combined with the diamond-like surface coating. Since the first metal transition layer The carbon content in the second metal transition layer and the second metal transition layer changes gradually. Therefore, the carbon content on the side combined with the diamond-like intermediate coating and the diamond-like surface coating is higher. Therefore, the diamond-like intermediate coating and the diamond-like surface coating can be reduced. The residual stress of the diamond-like surface coating improves the strength and toughness of the entire composite coating.

In addition, a diamond-like intermediate coating is provided in the composite transition layer, and a second metal transition layer with gradually decreasing carbon content is used as the bonding layer between the diamond-like intermediate coating and the metal coating, which can increase the bonding strength of the two. Through scientific and reasonable layer-by-layer design of the multi-layer structure, the composite transition layer can not only improve the strength of the composite transition layer, the metal substrate and the diamond-like surface coating, but also prevent the occurrence of cracks in the composite coating through the setting of boundaries between layers. Expansion improves the strength and toughness of the composite coating. Therefore, the composite coating provided by the invention has higher hardness and better toughness, and has excellent comprehensive properties.

Description of the drawings

In order to more clearly explain the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description The drawings illustrate some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting any creative effort.

Figure 1 is a schematic structural diagram of the combination of a diamond-like composite coating and a metal substrate provided in Embodiment 1 of the present invention.

Icon: 100-Metal substrate; 200-Composite transition layer; 201-Metal coating; 202-First metal transition layer; 203-Diamond-like intermediate coating; 204-Second metal transition coating; 300-Diamond-like surface coating layer.

Detailed ways

The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limitations of the invention. In addition, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.

One aspect of the present invention provides a diamond-like composite coating, including a diamond-like surface coating and a composite transition layer arranged in a layered structure; the composite transition layer includes a metal coating and a first metal transition layer arranged alternately in sequence. , diamond-like intermediate coating and second metal transition layer; the first metal transition layer is used to combine with the diamond-like surface coating; the metal coating or the first metal transition layer is used to combine with the metal substrate Combination; Along the direction from the metal coating to the diamond-like surface coating, the carbon content in the first metal transition layer gradually increases, and the carbon content in the second metal transition layer gradually decreases.

The diamond-like composite coating provided by the invention includes a diamond-like surface coating and a composite transition layer. The composite transition layer includes a metal coating, a first metal transition layer, a diamond-like intermediate coating and a second metal transition layer that are alternately arranged in sequence. , wherein the first metal transition layer is used to combine with the diamond-like surface coating, and the metal coating or the first metal transition layer is used to combine with the metal substrate.

When the first metal transition layer is combined with the metal substrate, since the lattice matching and stress of the first metal transition layer and the metal substrate are better matched, the bonding force between the first metal transition layer and the metal substrate is higher, thus The bonding force between the composite coating and the metal substrate is increased to prevent the composite coating and the metal substrate from falling off. At the same time, the carbon content in the first metal transition layer on the surface of the composite transition layer exists in a gradient manner, and the gradual increase in carbon content improves the bonding strength between the first metal transition layer and the diamond-like surface coating.

When a metal coating is provided between the first metal transition layer and the metal substrate, and the metal coating is combined with the metal substrate, the carbon content in the metal coating is consistent with the carbon content in the metal substrate, and the matching degree between the two is higher. This can further increase the bonding strength between the composite coating and the metal substrate and prevent the composite coating from falling off the metal substrate.

In addition, in the composite coating of the present invention, the first metal transition layer and the second metal transition layer are combined with the diamond-like intermediate coating, and the first metal transition layer is combined with the diamond-like surface coating. Since the first metal transition layer The carbon content in the second metal transition layer and the second metal transition layer changes gradually. Therefore, the carbon content on the side combined with the diamond-like intermediate coating and the diamond-like surface coating is higher. Therefore, the diamond-like intermediate coating and the diamond-like surface coating can be reduced. The residual stress of the diamond-like surface coating improves the strength and toughness of the entire composite coating.

In addition, a diamond-like intermediate coating is provided in the composite transition layer, and a second metal transition layer with gradually decreasing carbon content is used as the bonding layer between the diamond-like intermediate coating and the metal coating, which can increase the bonding strength of the two. Through scientific and reasonable layer-by-layer design of the multi-layer structure, the composite transition layer can not only improve the strength of the composite transition layer, the metal substrate and the diamond-like surface coating, but also prevent the occurrence of cracks in the composite coating through the setting of boundaries between layers. Expansion improves the strength and toughness of the composite coating. Therefore, the composite coating provided by the invention has higher hardness and better toughness, and has excellent comprehensive properties.

It should be noted that the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer in the composite transition layer of the present invention are alternately and repeatedly provided in this order. However, the composite transition layer of the present invention The starting layer is not limited. The starting layer of the composite transition layer may be a metal coating or a first metal transition layer, where the starting layer is used to combine with the metal substrate. However, the surface layer of the composite transition layer in the present invention, that is, the layer combined with the diamond-like surface coating, is the first metal transition layer.

In addition, the present invention does not specifically limit the number of repetitions of the alternate arrangement of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer in the composite transition layer, and it shall be at least once. For example, the structure of the composite transition layer can be: a metal coating, a first metal transition layer, a diamond-like intermediate coating, a second metal transition layer, a metal coating and a first metal transition layer; it can also be: a first metal transition layer layer, a diamond-like intermediate coating, a second metal transition layer, a metal coating and a first metal transition layer.

The metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer in the composite transition layer can also be repeated several times to form a [metal coating, first metal transition layer, diamond-like intermediate coating and the second metal transition layer] is a repeating unit. The structure of the composite transition layer can be, for example: the first repeating unit, the second repeating unit, ..., the Nth repeating unit, metal coating layer and the first metal transition layer, where N≥1 and is a natural number.

In one embodiment of the present invention, the ratio of the thicknesses of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer is (3-4): ( 1-2):(3-4):(1-2).

By reasonably setting the relative thicknesses between the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer, large thickness deviations are prevented from weakening the force between the layers. , thereby further increasing the bonding strength between layers in the composite transition layer.

In the above embodiment, the thickness ratio of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer is not limited to, for example, 3:1:3. :1, 4:1:3:1, 3:2:1:1, 3:2:4:1, 3:2:4:2 or 4:2:4:2.

In one embodiment of the present invention, the sum of the single layer thicknesses of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer is 10 to 200 nm. By limiting the sum of the single layer thicknesses of each coating layer, the thickness range of each coating layer in the composite transition layer can be further defined, thereby further improving the toughness between layers in the composite transition layer.

In the above embodiment, the sum of the single layer thicknesses of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer is not limited to, for example, 10 nm or 20 nm. , 50nm, 70nm, 100nm, 120nm, 150nm, 170nm or 200nm.

In one embodiment of the present invention, the thickness of the composite transition layer is 2-10 μm, preferably 3-9 μm. By limiting the thickness range of the composite transition layer, the toughness and strength of the composite coating can be further improved by preventing the composite transition layer from being too thick, resulting in poor toughness, or being too thin, resulting in reduced strength.

In the above embodiment, the thickness of the composite transition layer is not limited to, for example, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm or 10 μm.

In one embodiment of the present invention, the metal coating, the first metal transition layer and the second metal transition layer are all stainless steel layers.

In order to solve the problem that the diamond-like film is easy to fall off after plating a diamond-like film on the surface of a stainless steel substrate, the stainless steel layer is used as the metal coating and the first metal transition layer to improve the bonding strength of the composite coating and the stainless steel substrate. Among them, the stainless steel layer as the metal coating is combined with the stainless steel base, and the bonding strength between the two is higher.

In this embodiment, by arranging a composite coating on the surface of the stainless steel substrate, the hardness of the surface of the stainless steel material is increased, the friction coefficient is reduced, and the corrosion resistance and chemical stability are improved. By arranging a composite transition layer between the stainless steel substrate and the diamond-like surface coating, the bonding force between the stainless steel substrate and the diamond-like surface coating is improved, the residual stress of the diamond-like surface coating is reduced, and the diamond-like surface coating is prevented from being Comes off on stainless steel base.

A second aspect of the present invention provides a method for preparing the above-mentioned diamond-like composite coating, which uses a deposition method to alternately prepare a metal coating, a first metal transition layer, a diamond-like intermediate coating and a second metal transition layer. After obtaining the composite transition layer whose surface layer is the first metal transition layer, a diamond-like surface coating is deposited on the surface of the composite transition layer to obtain a diamond-like composite coating.

In the above preparation method, a deposition method is used to prepare the composite transition layer and the diamond-like surface coating. This method can reduce the number of metal coatings, first metal transition layers, diamond-like intermediate coatings, second metal transition layers, and diamond-like surface coatings. Defects in the layers reduce the stress generated by the bonding and improve the bonding force between the layers.

In one embodiment of the present invention, a metal coating is first deposited and prepared by magnetron sputtering, and carbon doping is performed during the deposition of a metal film on the surface of the metal coating to obtain a first metal transition layer with a gradually increasing carbon content. , depositing and preparing a diamond-like intermediate coating on the surface of the obtained first metal transition layer, and then performing metal doping during the process of depositing a diamond-like film on the surface of the obtained diamond-like intermediate coating to obtain a second metal transition layer with a gradually decreasing carbon content; After that, the preparation process of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer is repeated, and finally a composite transition layer with the first metal transition layer as the surface layer is obtained, and then a composite transition layer is formed on the surface of the composite transition layer. Deposit a diamond-like surface coating to obtain a diamond-like composite coating.

In one embodiment of the invention, the preparation method includes the following steps:

Step a) Use the magnetron sputtering method to deposit and prepare the metal coating: the process parameters include: the vacuum chamber pressure is 0.2~1.3Pa, inert gas is introduced, the inert gas flow is 50~400sccm, and the power of the metal target is 1~ 2.4KW, substrate bias voltage -100~-300, deposition time 5~10min, to obtain metal coating;

Step b): After step a) is completed, turn on the carbon source target and increase the power of the carbon source target from 0KW to 1-2KW within 3-5 minutes. At the same time, increase the power of the metal target from 1-2.4KW within the same time. Reduce to 0KW to obtain the first metal transition layer;

Step c): After step b) is completed, maintain the power of the carbon source target for sputtering deposition for 5 to 10 minutes to obtain a diamond-like intermediate coating;

Step d): After step c) is completed, turn on the metal target and increase the power of the metal target from 0KW to 1-2.4KW within 3-5 minutes. At the same time, reduce the power of the metal target from 1-2KW within the same time. 0KW, obtain the second metal transition layer;

Step e): Repeat the process of steps a) to d) to finally obtain a composite transition layer whose surface layer is the first metal transition layer;

Step f): Preparing a diamond-like surface coating by depositing on the surface of the composite transition layer obtained in step e) by magnetron sputtering. The process parameters include: passing inert gas, the power of the carbon source target is 1 to 2KW, and the substrate bias voltage The substrate bias voltage is -10~-300V, and the sputtering deposition time is 5~10min.

In the above embodiment, the first metal transition layer is formed by reducing the power of the metal target and increasing the power of the carbon source target after the deposition of the metal coating is completed. The power of the metal target is reduced to 0KW and the power of the carbon source target is reduced in the same period of time. It is obtained by increasing the source target power to the required value and performing cross deposition. The first metal transition layer obtained by this method has higher bonding force with the metal coating and the diamond-like intermediate coating, and has fewer defects between layers.

In the same way, the second metal transition layer is formed after the diamond-like intermediate coating is deposited. By reducing the power of the carbon source target and increasing the power of the metal target, the power of the carbon source target is reduced to 0KW within the same time. It is obtained by increasing the power of the metal target to the required value and performing cross-deposition.

It can be understood that the above-mentioned carbon source target material includes but is not limited to graphite target material, and it is sufficient that the diamond-like film can be deposited through ion bombardment sputtering. Similarly, the above-mentioned metal target materials include but are not limited to stainless steel target materials, which can be selected according to the actual material of the metal substrate. Among them, the inert gas includes but is not limited to argon, neon or xenon.

In one embodiment of the present invention, a magnetron sputtering method is used to deposit a diamond-like layer on the first metal layer; optionally, the process parameters for depositing the diamond-like layer by magnetron sputtering include: performing in an inert atmosphere For deposition, the power of the graphite target is 90~110W, the substrate bias voltage is 0~100V, and the deposition time is 45~60min.

In one embodiment of the present invention, the composite transition layer is deposited on the surface of a metal substrate using a magnetron sputtering method. By directly depositing and preparing the composite coating on the surface of the corresponding metal substrate, the metal material covered with the composite coating can be directly obtained, which facilitates the processing and production of later tools.

In one embodiment of the present invention, the metal substrate is pretreated first, and then the composite transition layer is prepared.

Through pretreatment, the dirt on the surface of the metal substrate and the lattice defects on the surface of the metal substrate are removed to improve the surface bonding degree between the composite transition layer and the metal substrate, thereby improving the bonding strength.

In one embodiment of the present invention, the metal substrate is a stainless steel substrate, die steel, high speed steel or cemented carbide. For the above-mentioned substrate, the pretreatment includes the steps of cleaning liquid cleaning, glow cleaning and ion etching cleaning.

Cleaning fluid cleaning can remove dirt from the surface of metal substrates. For example, the method of cleaning with a cleaning solution includes the following steps: first, ultrasonic cleaning the metal substrate, cleaning with acetone and ethanol for 10 to 20 minutes respectively, then cleaning with deionized water, and then blowing dry with nitrogen with a purity of ≥99.5%. Finally, it is placed in a blast drying oven at 80 to 150°C for drying treatment.

In one embodiment of the present invention, the process parameters of the glow cleaning include: inert gas, inert gas flow rate 300-500 sccm, working pressure 1.0-1.7 Pa, substrate bias -500-800 V, cleaning time 10～30min;

The purpose of glow cleaning on a metal substrate is to clean the substrate surface through the impact of charged particles, remove impurities such as oxide films on the substrate surface, leak out the more active metal surface, and improve the metal coating or first metal transition layer Bonding strength with metal matrix.

In one embodiment of the present invention, the process parameters of the ion etching cleaning include: passing in inert gas, inert gas flow rate 70-500 sccm, ion source voltage 20-30 V, working pressure 0.5-1.7 Pa, substrate bias It is -100~-800V, and the cleaning time is 10~30min.

Ion etching cleaning uses inert gas ionized into plasma in the ion source to perform ion bombardment cleaning on the metal substrate. The purpose of ion etching cleaning of metal substrates is that compared with glow cleaning, plasma etching energy is higher, the density of charged particles is greater, and the effect of removing the oxide layer is more obvious, thereby further improving the contact between the metal coating or the first metal transition layer and Bonding strength of metal matrix.

In one embodiment of the present invention, a method for preparing a diamond-like composite coating includes the following steps:

Step a) Cleaning solution cleaning: First, ultrasonic clean the metal substrate, clean it with acetone and ethanol for 10 to 20 minutes respectively, then clean it with deionized water, then blow it dry with nitrogen with a purity of ≥99.5%, and finally put it into the drum. Dry in an air drying oven at 80-150°C; fix the dried sample in an ion source/arc ion plating composite coating equipment for glow cleaning;

Step b) Glow cleaning: pass in inert gas, the inert gas flow rate is 300 to 500 sccm, the working pressure is 1.0 to 1.7 Pa, the substrate bias voltage is -500 to -800V, and the cleaning time is 10 to 30 minutes;

Step c) Ion etching cleaning: After the glow cleaning is completed, turn on the ion source to perform ion bombardment cleaning on the sample. The inert gas flow rate is 70~500 sccm, the ion source voltage is 20~30V, the working pressure is 0.5~1.7Pa, and the substrate bias voltage is 0.5~1.7Pa. -100～-800V, cleaning time 10～30min;

Step d) prepare the composite transition layer and diamond-like surface coating. The specific process is:

1) Use magnetron sputtering method to deposit and prepare metal coating: process parameters include: vacuum chamber pressure is 0.2~1.3Pa, inert gas is introduced, inert gas flow is 50~400sccm, and the power of the metal target is 1~2.4 KW, substrate bias voltage -100~-300, deposition time 5~10min, obtain metal coating;

2): After step 1) is completed, turn on the carbon source target and increase the power of the carbon source target from 0KW to 1-2KW within 3-5 minutes. At the same time, reduce the power of the metal target from 1-2.4KW within the same time. to 0KW, the first metal transition layer is obtained;

3): After step 2) is completed, maintain the power of the carbon source target for sputter deposition for 5 to 10 minutes to obtain a diamond-like intermediate coating;

4): After step 3) is completed, turn on the metal target and increase the power of the metal target from 0KW to 1-2.4KW within 3-5 minutes. At the same time, reduce the power of the metal target from 1-2KW to 0KW within the same time. , obtain the second metal transition layer;

5): Repeat steps 1) to 4) to finally obtain a composite transition layer whose surface layer is the first metal transition layer;

6): Preparing a diamond-like surface coating by depositing on the surface of the composite transition layer obtained in step 5) by magnetron sputtering. The process parameters include: passing inert gas, the power of the carbon source target is 1 to 2KW, and the substrate bias is The bias voltage is -10~-300V, the sputtering deposition time is 5~10min, and after the deposition is completed, a diamond-like composite coating is obtained on the surface of the metal substrate.

A third aspect of the present invention provides the use of the above diamond-like composite coating in equipment surface protection.

The diamond-like composite coating provided by the invention can be widely used for surface protection in many fields such as electromechanical systems, automobile parts, aerospace, and medical equipment.

A fourth aspect of the present invention provides a coated tool, including a tool body, the surface of which is combined with the above diamond-like composite coating or the diamond-like composite coating prepared by the above preparation method.

The present invention will be further described in detail below with reference to examples and comparative examples.

Example 1

As shown in Figure 1, this embodiment is a diamond-like composite coating, including a diamond-like surface coating 300 and a composite transition layer 200 arranged in a layered structure; the composite transition layer 200 includes metal coatings 201, The first metal transition layer 202, the diamond-like intermediate coating 203 and the second metal transition layer 204; the first metal transition layer 202 is used to combine with the diamond-like surface coating 300; the metal coating 201 or the first metal transition layer 202 is used for When combined with the metal substrate 100; along the direction from the metal coating 201 to the diamond-like surface coating 300, the carbon content in the first metal transition layer 202 gradually increases, and the carbon content in the second metal transition layer 204 gradually decreases. The composite coating in this embodiment is coated on the surface of the metal substrate 100 .

The diamond-like composite coating is prepared by the following method:

Step a) Cleaning solution cleaning: First put the sample into distilled water for ultrasonic cleaning for 10 minutes, then put the sample into acetone solution for ultrasonic cleaning for 15 minutes, then put the sample into absolute ethanol solution for ultrasonic cleaning for 15 minutes, and then use dry nitrogen to clean it. Blow dry the surface of the substrate, and finally put the sample into a blast drying oven to dry at 120°C; fix the dried sample on the turntable in the coating equipment; and vacuum. When the vacuum chamber pressure reaches 5.0×10 ^-3 Pa, turn on the heating power to heat and bake the vacuum chamber. The heating temperature is 400°C. During the heating process, the turntable system is turned on to allow the sample to pass through the air; when the vacuum degree reaches 3.0 When ×10 ^-3 Pa, glow cleaning begins;

Step b) Glow cleaning: Pour argon gas into the vacuum chamber, control the argon gas flow so that the working pressure is 1.3Pa, and the substrate bias voltage is -600V. Glow cleaning is performed on the substrate, and the cleaning time is 20 minutes;

Step c) Ion etching cleaning: After the glow cleaning is completed, turn on the ion source to perform ion bombardment cleaning on the sample. The ion source current is 25A, the argon flow is 300sccm, the working pressure is 1.3Pa, the substrate bias is -500V, and the cleaning time is 20min. ;

Step d): After the ion etching cleaning is completed, introduce argon gas with a flow rate of 200 sccm, adjust the vacuum chamber pressure to 1 Pa, turn on the DC magnetron stainless steel target, the power of the stainless steel target is 2.4KW, and the substrate bias voltage is -200V, and perform metal coating. Layer preparation; after 8 minutes, turn on the graphite target power supply, and increase the graphite target power from 0KW to 2KW at a uniform speed within 4 minutes. At the same time, the stainless steel target power decreases to 0KW at a uniform speed to prepare the first metal transition layer; when the graphite target power rises to 2KW After that, prepare the diamond-like intermediate coating for 5 minutes; then turn on the power of the stainless steel target, and increase the power of the stainless steel target from 0KW to 2.4KW at a constant speed within 4 minutes, while the power of the graphite target decreases to 0KW at a constant speed to prepare the second metal transition layer; After the graphite target is turned off, maintain the power of the stainless steel target and continue deposition to prepare the metal coating;

This reciprocating cycle prepares a composite transition layer whose surface layer is the first metal transition layer;

Step e): After step d) is completed, close the stainless steel target, set the power of the graphite target to 2KW, and the base bias voltage to -200V. Sputter and deposit for 7 minutes to obtain a diamond-like surface coating on the surface of the composite transition layer. Finally, The surface of the metal substrate is coated with a diamond-like composite coating.

Example 2

This embodiment is a diamond-like composite coating with the same structure as in Embodiment 1.

The diamond-like composite coating in this embodiment is prepared by the following method:

Step a) Cleaning solution cleaning: First put the sample into distilled water for ultrasonic cleaning for 10 minutes, then put the sample into acetone solution for ultrasonic cleaning for 15 minutes, then put the sample into absolute ethanol solution for ultrasonic cleaning for 15 minutes, and then use dry nitrogen to clean it. Blow dry the surface of the substrate, and finally put the sample into a blast drying oven to dry at 130°C; fix the dried sample on the turntable in the coating equipment; and vacuum. When the pressure of the vacuum chamber reaches 5.0×10 ^-3 Pa, turn on the heating power to heat and bake the vacuum chamber. The heating temperature is 300°C. During the heating process, the turntable system is turned on to allow the sample to pass through the air; when the vacuum degree reaches 3.0 When ×10 ^-3 Pa, glow cleaning begins;

Step b) Glow cleaning: Pour argon gas into the vacuum chamber, control the argon gas flow so that the working pressure is 1.2Pa, and the substrate bias voltage is -700V. Glow cleaning is performed on the substrate, and the cleaning time is 12 minutes;

Step c) Ion etching cleaning: After the glow cleaning is completed, turn on the ion source to perform ion bombardment cleaning on the sample. The ion source current is 25A, the argon flow is 500sccm, the working pressure is 1.7Pa, the substrate bias is -200V, and the cleaning time is 25min. ;

Step d): After the ion etching cleaning is completed, introduce argon gas with a flow rate of 400 sccm, adjust the vacuum chamber pressure to 1.3 Pa, turn on the DC magnetron stainless steel target, the stainless steel target power is 2KW, and the substrate bias is -150V, and perform metal coating. Layer preparation; after 10 minutes, turn on the graphite target power supply, and increase the graphite target power from 0KW to 1.5KW at a uniform speed within 5 minutes. At the same time, the stainless steel target power decreases to 0KW at a uniform speed to prepare the first metal transition layer; when the graphite target power rises to After 1.5KW, set the substrate bias voltage to -100V and maintain it for 10 minutes to prepare the diamond-like intermediate coating; then turn on the stainless steel target power supply and increase the stainless steel target power from 0KW to 2KW at a uniform speed within 5 inches, while the graphite target power drops to 0KW at a uniform speed. Prepare the second metal transition layer; after the graphite target is turned off, maintain the power of the stainless steel target to continue deposition to prepare the metal coating;

This reciprocating cycle prepares a composite transition layer whose surface layer is the first metal transition layer;

Step e): After step d) is completed, close the stainless steel target, set the power of the graphite target to 1.5KW, and the base bias voltage to -200V. Sputter and deposit for 10 minutes to obtain a diamond-like surface coating on the surface of the composite transition layer. Finally, A diamond-like composite coating is obtained on the surface of the metal substrate.

Example 3

This embodiment is a diamond-like composite coating with the same structure as in Embodiment 1.

The diamond-like composite coating in this embodiment is prepared by the following method:

Step a) Cleaning solution cleaning: First put the sample into distilled water for ultrasonic cleaning for 15 minutes, then put the sample into acetone solution for ultrasonic cleaning for 20 minutes, then put the sample into absolute ethanol solution for ultrasonic cleaning for 10 minutes, and then use dry nitrogen to clean it. Blow dry the surface of the substrate, and finally put the sample into a blast drying oven to dry at 150°C; fix the dried sample on the turntable in the coating equipment; and vacuum. When the vacuum chamber pressure reaches 5.0×10 ^-3 Pa, turn on the heating power to heat and bake the vacuum chamber. The heating temperature is 200°C. During the heating process, the turntable system is turned on to allow the sample to pass through the air; when the vacuum degree reaches 3.0 When ×10 ^-3 Pa, glow cleaning begins;

Step b) Glow cleaning: Pour argon gas into the vacuum chamber, control the argon gas flow so that the working pressure is 1.0Pa, and the substrate bias voltage is -500V. Glow cleaning is performed on the substrate, and the cleaning time is 30 minutes;

Step c) Ion etching cleaning: After the glow cleaning is completed, turn on the ion source to perform ion bombardment cleaning on the sample. The ion source current is 20A, the argon flow rate is 150sccm, the working pressure is 0.8Pa, the substrate bias is -300V, and the cleaning time is 25min. ;

Step d): After the ion etching cleaning is completed, introduce argon gas with a flow rate of 150 sccm, adjust the vacuum chamber pressure to 0.8 Pa, turn on the DC magnetron stainless steel target, the power of the stainless steel target is 1.4KW, and the substrate bias is -200V, and perform metal processing. Coating preparation; after 10 minutes, turn on the graphite target power supply, and increase the graphite target power from 0KW to 1KW at a uniform speed within 5 minutes. At the same time, the stainless steel target power decreases to 0KW at a uniform speed to prepare the first metal transition layer; when the graphite target power rises to After 1KW, set the substrate bias voltage to -150V and maintain it for 10 minutes to prepare the diamond-like intermediate coating; then turn on the stainless steel target power supply and increase the stainless steel target power from 0KW to 1.4KW at a uniform speed within 5 minutes, while the graphite target power drops to 0KW at a uniform speed. Prepare the second metal transition layer; after the graphite target is turned off, maintain the power of the stainless steel target to continue deposition to prepare the metal coating;

This reciprocating cycle prepares a composite transition layer whose surface layer is the first metal transition layer;

Step e): After step d) is completed, close the stainless steel target, set the power of the graphite target to 1.5KW, and the base bias voltage to -300V. Sputter and deposit for 7 minutes to obtain a diamond-like surface coating on the surface of the composite transition layer. Finally, A diamond-like composite coating is obtained on the surface of the metal substrate.

Comparative example 1

This comparative example is a diamond-like coating that contains only one layer of diamond-like coating. The diamond-like coating is deposited on the pre-treated stainless steel substrate surface using the magnetron sputtering method of step e) in Example 1.

Performance tests were conducted on the stainless steel materials whose surfaces were covered with diamond-like composite coatings in Examples 1-3 and the stainless steel materials whose surfaces were covered with diamond-like coatings in Comparative Example 1. Anton Paar's NHT2 nanoindentation instrument was used to test the hardness of the coating, and a Super thin film stress meter was used to test the residual compressive stress of the coating. Anton Paar's MST nanoscratch instrument was used to test the pressure load when the coating peeled off. The test results are listed below. in Table 1.

Table 1 Performance test results

It can be seen from the data in Table 1 that the pressure load of the composite coatings in Examples 1-3 when peeling off is much higher than that of the coating in Comparative Example 1. In addition, the hardness of the coating in Comparative Example 1 is also lower, and the residual stress is more than double that of Examples 1-3. This shows that the diamond-like composite coating provided by the present invention has a higher degree of bonding with the stainless steel substrate.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, but not to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or substitutions do not deviate from the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention. scope.

Claims (8)

1. The preparation method of the diamond-like composite coating is characterized in that the diamond-like composite coating comprises a diamond-like surface coating and a composite transition layer which are arranged in a layered structure;

the composite transition layer comprises a metal coating, a first metal transition layer, a diamond-like intermediate coating and a second metal transition layer which are sequentially and alternately arranged; the first metal transition layer is used for being combined with the diamond-like surface coating; the metal coating or the first metal transition layer is used for being combined with a metal substrate;

the carbon content in the first metal transition layer gradually increases and the carbon content in the second metal transition layer gradually decreases along the direction from the metal coating to the diamond-like surface coating;

the preparation method of the diamond-like composite coating comprises the following steps:

alternately preparing a metal coating, a first metal transition layer, a diamond-like intermediate coating and a second metal transition layer by using a deposition method, obtaining a composite transition layer with a surface layer being the first metal transition layer, and then depositing a diamond-like surface coating on the surface of the composite transition layer to obtain a diamond-like composite coating;

firstly, preparing a metal coating by utilizing a magnetron sputtering method, carrying out carbon doping in the process of depositing a metal film on the surface of the obtained metal coating to obtain a first metal transition layer with gradually increased carbon content, preparing a diamond-like intermediate coating by depositing on the surface of the obtained first metal transition layer, and then carrying out metal doping in the process of depositing a diamond-like film on the surface of the obtained diamond-like intermediate coating to obtain a second metal transition layer with gradually reduced carbon content; then repeating the preparation processes of the metal coating, the first metal transition layer, the diamond-like intermediate coating and the second metal transition layer to finally obtain a composite transition layer with the surface layer being the first metal transition layer, and then depositing a diamond-like surface coating on the surface of the composite transition layer to obtain the diamond-like composite coating;

the preparation method comprises the following steps:

step a) preparing a metal coating by utilizing a magnetron sputtering method deposition: the technological process parameters include: the pressure of the vacuum chamber is 0.2 to 1.3Pa, inert gas is introduced, the flow rate of the inert gas is 50 to 400sccm, the power of the metal target is 1 to 2.4KW, the substrate bias voltage is-100 to-300, and the metal coating is obtained after deposition; the deposition time is 5-10 min;

step b): starting a carbon source target after the step a) is completed, enabling the power of the carbon source target to be increased from 0KW to 1-2 KW within 3-5 min, and simultaneously enabling the power of the metal target to be reduced from 1-2.4 KW to 0KW within the same time to obtain a first metal transition layer;

step c): after the step b) is completed, maintaining the power sputtering deposition of the carbon source target material for 5-10 min to obtain a diamond-like intermediate coating;

step d): starting the metal target after the step c) is completed, so that the power of the metal target is increased from 0KW to 1-2.4 KW within 3-5 min, and simultaneously, the power of the metal target is reduced from 1-2 KW to 0KW within the same time, so as to obtain a second metal transition layer;

step e): repeating the steps a) to d) to finally obtain the composite transition layer with the surface layer being the first metal transition layer;

step f): preparing a diamond-like surface coating on the surface of the composite transition layer obtained in the step e) by a magnetron sputtering method, wherein the technological parameters comprise: introducing inert gas, wherein the power of the carbon source target is 1-2 KW, and the substrate bias voltage is-10 to-300V, so as to obtain the diamond-like surface coating after deposition; the deposition time is 5-10 min.

2. The method of producing a diamond-like composite coating according to claim 1, wherein the ratio of the thicknesses of the metal coating, the first metal transition layer, the diamond-like intermediate coating, and the second metal transition layer is (3-4): 1-2): 3-4: 1-2.

3. The method of producing a diamond-like composite coating according to claim 1, wherein the sum of the monolayer thicknesses of the metal coating, the first metal transition layer, the diamond-like intermediate coating, and the second metal transition layer is 10 to 200nm;

the thickness of the composite transition layer is 2-10 mu m.

4. A method of preparing a diamond-like composite coating according to claim 3, wherein the thickness of the composite transition layer is 3-9 μm.

5. The method according to any one of claims 1 to 4, wherein the composite transition layer is deposited on the surface of the metal substrate by a magnetron sputtering method.

6. The method according to claim 5, wherein the metal substrate is pretreated and then the composite transition layer is prepared;

the metal substrate comprises a stainless steel substrate, a work die steel, high-speed steel or hard alloy;

the pretreatment comprises the steps of cleaning with cleaning liquid, glow cleaning and ion etching cleaning;

the glow cleaning process parameters comprise: introducing inert gas, wherein the flow rate of the inert gas is 300-500 sccm, the working pressure is 1.0-1.7 Pa, and the substrate bias voltage is-500 to-800V;

the cleaning time in the glow cleaning is 10-30 min;

the technological parameters of the ion etching cleaning comprise: introducing inert gas, wherein the flow rate of the inert gas is 70-500 sccm, the voltage of an ion source is 20-30V, the working pressure is 0.5-1.7 Pa, and the substrate bias voltage is-100-800V;

the cleaning time in the ion etching cleaning is 10-30 min.

7. Use of the diamond-like composite coating prepared by the preparation method according to any one of claims 1 to 6 in equipment surface protection.

8. A coated tool comprising a tool body, characterized in that: a diamond-like composite coating prepared by the preparation method of any one of claims 1 to 6 is bonded to the surface of the tool body.