TW201823509A - Knife composite coating, knife and preparation method of knife composite coating capable of depositing a multilayer nanometer composite coating on the surface - Google Patents

Abstract

The present invention is applicable to the technical field of knife coating, and discloses a knife composite coating, a knife and a preparation method of knife composite coating. The knife composite coating includes a base layer coated on the knife body and a top layer disposed on the outermost side. The base layer is a diamond layer or a cubic boron nitride layer, and the base layer has a thickness of 1 to 40 [mu]m. The top layer is a tetrahedral amorphous carbon film layer, and has a thickness of 0.01 to 15 [mu]m. The knife includes a knife base and the aforementioned knife composite coating. The preparation method of knife composite coating is provided to prepare the aforementioned knife composite coating. With the knife composite coating, the knife and the preparation method of knife composite coating in accordance with the present invention, it is able to deposit a multilayer nanometer composite coating with high hardness, low friction coefficient, excellent bonding force and high temperature resistance on the surface, so as to significantly improve the wear resistance of the knife, greatly reduce the needle breakage rate, and avoid the problems of chip accumulation edge and blockage of chip exhaust slot.

Description

Tool composite coating, cutter and preparation method of tool composite coating

The invention belongs to the technical field of cutting tool coatings, and particularly relates to a cutting tool composite coating, a cutting tool and a preparation method of the cutting tool composite coating.

With the development of the economy and society, a large number of difficult-to-machine materials such as graphite materials, aluminum alloys, carbon fiber composite materials, metal composite materials, and ceramic substrates appear on the market, which puts forward higher requirements for cutting tools. Firstly, this kind of material has high hardness, hard alloy micro-tools have great wear and short life; secondly, the cutting edge is easy to form chip edges, which seriously reduces the processing quality; once again, chips are easily blocked in the chip discharge groove of the tool, causing poor dust discharge. Seriously reduce product quality. Since uncoated micro-tools cannot meet the existing processing requirements, new coating materials are urgently needed to be applied to micro-tools to overcome this processing problem.

In order to improve the life and processing quality of micro-tools, many companies at home and abroad have performed surface modification treatments on micro-tools, such as chemical vapor deposition (CVD) and physical vapor deposition (PVD). At the same time, the technology has been widely used in steel In other metal processing, the life of non-micro tools can be increased by more than twice, but the use of difficult-to-machine materials such as graphite materials, aluminum alloys, carbon fiber composite materials, metal composite materials, ceramic substrates is less, and new materials are urgently needed to solve The problem.

The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art, and to provide a tool composite coating, a method for preparing a tool and a tool composite coating, which can significantly improve the wear resistance of a miniature tool while avoiding built-in edges. up edge) and clogging the chip flute.

The technical solution of the present invention is: a tool coating, comprising a base layer coated on the tool body and a top layer located on the outermost side, the base layer is a diamond layer or a cubic boron nitride layer, and the thickness of the base layer is 1 to 40 μm, The top layer is a tetrahedral amorphous carbon film layer and has a thickness of 0.01 to 15 μm.

Preferably, at least one intermediate layer is further provided between the base layer and the top layer. The intermediate layer includes any one of a transition layer and a core layer, or the intermediate layer includes a laminated transition layer and a core layer; the transition layer is a Me layer and The thickness is 0.01 to 10 μm, the core layer is a MeX layer and the thickness is 0.01 to 15 μm, where Me represents Al, Ti, Cr, V, Mn, Fe, Co, Ni, Cu, Zr and other metallic elements and non-metallic elements in Si. At least one; X represents one, two, or three of N, C, and B.

The present invention also provides a cutter. The cutter comprises a cutter base, and a part or all of the surface of the cutter base is provided with the above-mentioned cutter composite coating.

The invention also provides a method for preparing a cutter composite coating, which includes the following steps:

(1) Preparation of the substrate layer: The tool substrate is put into a CVD device, and a first semi-finished product is obtained by forming a substrate layer on the surface of the tool substrate by the CVD device, and the substrate layer is a diamond layer or a cubic boron nitride layer;

(2) Preparation of a tetrahedral amorphous carbon film layer: A tool substrate having a base layer is put into a physical vapor phase device to form a tetrahedral amorphous carbon film layer on the outermost side.

Preferably, after the base layer is prepared and before the tetrahedral amorphous carbon film layer is formed, the preparation method further includes at least one of the following two steps:

(1) Preparation of the transition layer: Put the first semi-finished product into the PVD composite coating equipment, turn on the metal vapor vacuum arc ion source, perform Me ion implantation, Me ions are implanted on the surface of the first semi-finished product, and then use arc ion plating technology Depositing a Me transition layer on the surface of the first semi-finished product, Me represents at least one of Al, Ti, Cr, V, Mn, Fe, Co, Ni, Cu, Zr, and non-metallic element Si;

(2) Preparation of the core layer: Put the second semi-finished product into the arc ion plating equipment, and pass in a gas containing at least one element of N, C, and B. The target material used in the arc ion plating equipment is Me target, and arc ion plating is used. The technology deposits a MeX core layer on the transition layer and obtains a third semi-finished product. X represents one or two or three of N, C, and B.

Preferably, the transition layer is a Me layer and has a thickness of 0.01 to 10 μm; the core layer is a MeX layer and has a thickness of 0.01 to 15 μm; and the thickness of the tetrahedral amorphous carbon film layer is 0.01 to 15 μm.

Preferably, the base layer is a diamond layer or a cubic boron nitride layer; the thickness of the base layer is 4 to 20 μm, the transition layer is a Me layer and the thickness is 0.1 to 3 μm; the core layer is 0.1 to 5 μm, tetrahedral amorphous carbon The thickness of the film layer is 0.05 to 5 μm. Preferably, in the step of preparing the substrate layer, the temperature of the hot wire in the hot wire CVD equipment is 2000-2400 ° C, the pressure in the growth chamber is 1.5-10 Kpa, the flow rate of the reaction source gas is 150-320 sccm, and the surface temperature of the tool substrate The temperature is 600-1000 ° C, and the growth time of the substrate is 5-20 hours.

Preferably, in the step of preparing the transition layer, when the vacuum of the PVD composite coating equipment reaches 5.0 × 10 ^-4 Pa, the metal vapor vacuum arc ion source is turned on.

Preferably, in the step of preparing the core layer, a gas containing at least one of N, C, and B, such as CH ₄ , N _2, etc., is passed; the flow rate of the gas is 50 to 500 sccm, and the arc current of the arc ion plating is 50 To 100A, pulse bias peak value -100 to -500 V, duty cycle 10% to 80%.

Preferably, in the step of preparing the core layer, the arc current of the arc ion plating is 50 to 100 A, the peak value of the pulse bias is -100 to -500 V, and the duty ratio is 10% to 80%.

The cutter composite coating provided by the present invention, and a method for preparing a cutter composite coating, by depositing a multilayer nano composite coating with high hardness, low friction coefficient, good bonding force, and high temperature resistance on the surface of the tool, When processing graphite materials, aluminum alloys, carbon fiber composite materials, metal composite materials, ceramic substrates and other difficult-to-machine materials, it can significantly improve the wear resistance of the tool, greatly reduce the needle breakage rate, and increase the tool life to 4 to 20 Times, and can avoid the problem of chip accumulation edge and clogging the chip groove.

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

It should be noted that when an element is referred to as being “fixed to” or “disposed on” another element, it may be directly on the other element or there may be a centered element at the same time. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present.

It should also be noted that the terms such as left, right, up, and down in the embodiments of the present invention are merely relative concepts or reference to the normal use status of the product, and should not be considered as restrictive. .

As shown in FIG. 1 and FIG. 2, a cutter composite coating provided by an embodiment of the present invention includes a base layer 1 coated on the tool body and an outermost top layer 4. The base layer 1 is a diamond layer or cubic nitrogen. Boron layer, the thickness of the base layer 1 is 1 to 40 μm, the top layer 4 is a tetrahedral amorphous carbon film layer with a thickness of 0.01 to 15 μm, and the top layer 4 is a tetrahedral amorphous carbon film (diamond-like structure of Ta-c structure) The nano-hardness is as high as 40 to 80 Gpa, and the tetrahedral amorphous carbon film can be prepared by physical vapor deposition, which improves the bonding force between the tetrahedral amorphous carbon film and the substrate, and due to the friction of the top 4 tetrahedral amorphous carbon film The coefficient can be lower than 0.1, and its hardness is high and the friction coefficient is small. By depositing a multilayer nano composite coating with high hardness, low friction coefficient, good bonding force and good high temperature resistance on the surface of the tool, it can process graphite materials and aluminum. Alloys, carbon fiber composite materials, metal composite materials, ceramic substrates and other difficult-to-machine materials can significantly improve the wear resistance of the tool, greatly reduce the needle breakage rate, and increase the tool life to 4 to 20 times. High to avoid product Chip edges and clogging of the flutes. In a specific application, the thickness of the tetrahedral amorphous carbon film may be 0.05 to 10 μm, preferably, the thickness of the tetrahedral amorphous carbon film may be 0.05 to 7 μm. In this embodiment, the thickness of the tetrahedral amorphous carbon film may be 0.05 to 5 μm, for example, 0.1 to 5 μm.

In specific applications, at least one intermediate layer is further provided between the base layer 1 and the top layer 4. The intermediate layer includes at least one of the transition layer 2 and the core layer 3. Or, the intermediate layer includes at least one set of the transition layer 2 and the core. Layer 3; that is, it may include a structure in which transition layers 2-core layers 3-transition layers 2-core layers 3 are sequentially stacked.

The transition layer 2 is a Me layer and has a thickness of 0.01 to 10 μm, and the core layer 3 is a MeX layer and has a thickness of 0.01 to 15 μm, where Me represents aluminum (Al), titanium (Ti), chromium (Cr), vanadium (V), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zr) and other metallic elements and at least one of the non-metallic elements Si, X represents nitrogen (N), carbon ( C), one or two or three of boron (B). The tetrahedral amorphous carbon film layer is composed of a tetrahedral amorphous carbon film layer composed of C element, and is composed of 40% to 95% of sp ³ bond carbon atoms as a skeleton. Preferably, the tetrahedral amorphous carbon film layer is composed of 40% Up to 90% of the sp ³ bond carbon atoms are composed of a skeleton. In this embodiment, the tetrahedral amorphous carbon film layer is composed of 50% to 90% of the sp ³ bond carbon atoms as a skeleton.

Specifically, the Raman spectrum analysis of the tetrahedral amorphous carbon film layer (Ta-C) is shown in FIG. 2.

The Raman spectroscopy analysis is used to determine the ID and IG values of the Ta-C film. ID represents the intensity of the Diamond peak and the wave number is 1300 to 1400 (for example, 1340 or about). IG represents the intensity of the Graphite peak and the wave number is 1500 to 1600 ( Such as 1580 or so). The intensity of the ID peak represents the content of sp ³ bonds to a certain extent. The fitting method uses a Gaussian function, and the area of the peak and the abscissa represents the content of the sp ² or sp ³ bond components.

In this embodiment, the base layer of the coating near the substrate is a pure metal Me layer with a thickness of 10 to 100 nm; the transition layer 2 is a MeX layer with a thickness of 80 to 300 nm; the core layer 3 is a MeAlX composite layer with a thickness of 0.4 to 5.0 μm; the top layer 4 is a diamond-like carbon (tetrahedral amorphous carbon film layer) of Ta-c structure, with a thickness of 0.05 to 5.0 μm.

An embodiment of the present invention further provides a cutter. The cutter includes a cutter base, and a cutting edge diameter of the cutter base can be 0.02 to 0.5 mm. A part or all of the surface of the tool base is provided with the above-mentioned tool composite coating. By depositing a multilayer nano composite coating with high hardness, low friction coefficient, good bonding force, and high temperature resistance on the surface of the tool, it processes graphite materials, aluminum alloys, carbon fiber composite materials, metal composite materials, ceramic substrates, etc. When the material is difficult to process, it can significantly improve the wear resistance of the tool, greatly reduce the needle breakage rate, and increase the service life of the tool to 4 to 20 times. At the same time, it can guarantee the processing quality, greatly improve the processing efficiency, and reduce the production cost.

An embodiment of the present invention also provides a method for preparing a tool composite coating, which can be used to prepare the above-mentioned tool composite coating and a tool, including the following steps:

(1) Preparation of the substrate layer 1: The tool substrate is put into a CVD device, and the substrate layer 1 is formed on the surface of the tool substrate by the CVD device to obtain a first semi-finished product; the substrate layer 1 may be a diamond layer or a cubic boron nitride layer.

(2) Preparation of a tetrahedral amorphous carbon film layer: A tool substrate having a base layer 1 is placed in a physical vapor phase device to form a tetrahedral amorphous carbon film layer on the outermost side. A carbon target is provided in the physical vapor phase device to A tetrahedral amorphous carbon film layer is formed on the outermost layer of the coating.

Specifically, when the tetrahedral amorphous carbon film layer is prepared, the carbon target current in the physical vapor phase device is 10 to 50 A, the peak value of the pulse negative bias is -50 to -200 V, and the duty ratio is 30% to 50%.

Specifically, after preparing the base layer 1 and before preparing the tetrahedral amorphous carbon film layer, the preparation method further includes at least one of the following two steps:

(1) Preparation of transition layer 2: Put the first semi-finished product into the PVD composite coating equipment, turn on the metal vapor vacuum arc ion source, and perform Me ion implantation. Me ions are implanted on the surface of the first semi-finished product. A Me transition layer 2 is deposited on the surface of the first half of the finished product, where Me represents at least one of metal elements such as Al, Ti, Cr, V, Mn, Fe, Co, Ni, Cu, Zr and the non-metal element Si, to obtain a second semi-finished product ;

(2) Preparation of core layer 3: Put the second semi-finished product or the first semi-finished product into the arc ion plating equipment, and pass in a gas containing at least one element of N, C, and B. The target material used for the arc ion plating equipment is the Me target. Using arc ion plating technology to deposit MeX core layer 3 on transition layer 2 and obtain a third semi-finished product, X represents one or two or three of N, C, and B; and then deposit tetrahedral amorphous on core layer 3. The carbon film layer, or, continues to deposit the transition layer 2 on the core layer 3 and continues to deposit the core layer 3 on the transition layer 2, and finally, a tetrahedral amorphous carbon film layer is formed on the outermost side of the coating.

Specifically, the transition layer 2 is a Me layer and the thickness may be 0.01 to 10 μm; the core layer 3 is a MeX layer is 0.01 to 15 μm; and the thickness of the tetrahedral amorphous carbon film layer is 0.01 to 15 μm.

Specifically, the thickness of the base layer 1 may be 4 to 20 μm, the transition layer 2 may be a Me layer and the thickness may be 0.1 to 3 μm; the thickness of the core layer 3 may be 0.1 to 5 μm, and the thickness of the tetrahedral amorphous carbon film layer is 0.05. Up to 5 μm. Specifically, in the step 1 of preparing the base layer, the temperature of the hot wire in the CVD equipment may be 2000-2400 ° C, the pressure in the growth chamber may be 1.5-10Kpa, the flow rate of the reaction source gas may be 150-320sccm, and the surface of the tool substrate The temperature may be 600-1000 ° C, and the growth time of the substrate layer 1 may be 5-20 hours.

Specifically, in the step of preparing the transition layer 2, when the vacuum of the PVD composite coating equipment reaches 5.0 × 10 ^-4 Pa, the metal vapor vacuum arc ion source is turned on.

Specifically, a gas containing at least one of N, C, and B elements such as CH ₄ , N _2, etc. is passed in; the flow rate of the gas is 50 to 500 sccm, the arc current of the arc ion plating is 50 to 100 A, and the peak pulse bias voltage is -100. To -500 V with a duty cycle of 10% to 80%.

Specifically, in the step of preparing the core layer 3, the arc current of the arc ion plating is 50 to 100 A, the peak value of the pulse bias is -100 to -500 V, and the duty ratio is 10% to 80%.

In a specific application, before preparing the base layer 1, the tool substrate is pretreated. The pretreatment method includes the following steps:

(1) Clean the surface of the drill bit;

(2) De-Co chemical pretreatment on the drill bit; De-Co chemical pretreatment includes:

The WC phase of the drill bit is eroded by lye,

Use the acid solution to corrode the Co phase of the drill bit;

(3) roughening the surface of the drill bit;

Among them, when the WC phase of the bit is used to corrode the bit, the etched part is that the bit of the bit has a cutting edge and the length l from the cutting edge and the length of the bit groove L satisfy the relationship L1 / 10 ≤ l ≤ L9 / 10, that is, the bit of the bit The length of the part is L, and the length l of the etched part is greater than one tenth L and less than nine tenths L;

When the Co phase of the bit is eroded by an acid solution, the etched part is the bit of the bit containing the cutting edge of the bit, and the length l from the point of the bit and the length L of the bit groove satisfy the relationship L1 / 10 ≤ l ≤ L9 / 10, that is, the bit of the bit The length L is L, and the length l of the etched part is greater than one tenth L and less than nine tenths L. When the acid phase is used to etch the Co phase and the alkaline solution is used to etch the WC phase, the etched length is the same. The etched length is not more than nine tenths of the drill bit length and not less than one tenth of the drill bit length. Overcome the detrimental effect of the de-Co treatment on the strength of the tool substrate, and also ensure that the diamond coating has a good bonding force with the substrate, while not affecting the machining performance of the drill, the strength of the drill's edge will not be significantly reduced, in high-speed processing It is difficult to break the knife from time to time. In this embodiment, when the WC phase of the drill bit is etched by an alkaline solution, the etched part is that the length of the drill bit including the cutting edge and the length l from the cutting edge and the length of the drill groove L satisfy L / 3 ≤ l ≤ L / 2. That is, the length of the etched part l is not more than one-half of the length of the bit of the drill and not less than one-third of the length of the bit of the drill. When the Co phase of the drill is etched with an acid, the etched part is the bit of the bit with a cutting edge and The relationship between the length l from the tool tip and the drill groove length L satisfies L / 3 ≤ l ≤ L / 2, that is, the length of the erosion site l is not greater than one-half the length of the drill's blade and not less than the length of the drill's blade. one third.

The specific application process can refer to the following:

(1) Firstly use high-purity anhydrous alcohol to clean the tool substrate in high-power ultrasonic equipment, and then use a two-step method of acid-base to chemically remove the surface of the tool substrate from Co.

(2) The first layer (base layer 1) of the superhard composite coating is prepared by hot-wire CVD technology. The first layer is a diamond layer and the element is carbon (the first layer may also be a cubic boron nitride layer). Temperature of the hot filament CVD apparatus of filaments of 2000-2400 ℃, the growth chamber pressure of 1.5 ^-10 KPa; flow rate of source gas for 150-320sccm; substrate surface temperature of 600-1000 ℃, coating deposition growth time For 5-20 hours.

(3) The tool substrate for which the diamond layer has been prepared is clamped in a PVD composite coating equipment.

(4) When the vacuum reaches 5.0 × 10 ^-4 Pa, turn on the high-current metal vapor vacuum arc ion source (MEVVA source) to perform Me ion implantation. These ions are implanted in the electric field under the electric field of up to 5,000 to 8,000 volts. The surface of the processed tool workpiece is rooted to a certain depth under the surface of the tool substrate (hard alloy), which can significantly improve the binding force between the coating and the tool substrate.

(5) Deposition of Me metal transition layer 2 on the surface of base layer 1 by arc ion plating technology, arc current 50 to 100A, peak pulse bias -100 to -500 V, duty cycle 10% to 80%

(6) Pass in a gas containing at least one of N, C, and B elements, such as CH ₄ , N ₂ mixed gas, and use arc ion plating technology to deposit the core layer 3 on the metal transition layer 2. The target material used is Me target, the gas flow rate is 50 to 500 sccm, the arc current of arc ion plating is 50 to 100A, the pulse bias peak value is -100 to -500 V, and the duty ratio is 10% to 80%.

(7) A tetrahedral amorphous carbon film layer was prepared using a physical vapor phase technique, with a carbon target current of 10 to 50 A, a pulse negative bias peak of -50 to -200 V, and a duty cycle of 30 to 50%.

(8) Cool sampling.

The cutter composite coating provided in the embodiments of the present invention, a method for preparing a cutter and a cutter composite coating, use the CVD method to produce the base layer 1 (diamond coating or cubic boron nitride layer), mainly because of the hot-wire CVD method. Large, can uniformly deposit the base layer 1 on the surface of complex tools. As shown in Figure 1, the Raman spectrum shows that this layer is diamond.

During the preparation of the intermediate layer (transition layer 2), the physical and chemical properties of the surface of the micro-tools were changed by ion implantation and cleaning using Me plasma generated by a high-current metal vapor vacuum arc ion source (MEVVA source). First, when high-energy ions generated by the ion source hit the surface of the tool, the high-energy ions have a strong sputtering effect on the tool, which can remove impurities such as gas, liquid, and dust adsorbed on the tool surface, and provide an extremely clean surface for hard coating deposition. To enhance the binding force between the micro-tool and the subsequent hard coating; secondly, high-energy ions produce strong collisions and cascading collisions on the surface of the tool base. Some high-energy ions replace the original atoms of the tool base, and change the chemical composition of the tool surface. The surface forms a layer of mixed interface, which not only improves the mechanical properties such as the strength and hardness of the tool surface, but also enhances the bonding force between the hard coating and the tool substrate.

The metal Me transition layer 2 and MeX core layer 3 are deposited by using arc ion plating technology, which mainly utilizes the characteristics of high ionization rate of cathodic arc ion plating, which can further improve the bonding force between the coating and the substrate; The preparation of tetrahedral amorphous carbon film by physical vapor phase technology improves the bonding force between the tetrahedral amorphous carbon film and the substrate, so that the thickness of the tetrahedral amorphous carbon film can be increased to 5 μm or more.

The diamond / Me / MeX / tetrahedral amorphous carbon film prepared by the method provided by the present invention has a nano-hardness of the top 4-tetrahedral amorphous carbon film of 40 to 80 GPa, as shown in FIG. 3; the top 4-tetrahedral amorphous carbon. The friction coefficient of the film is lower than 0.1; the nano-hardness of the core layer 3MeX is as high as 30 to 45 Gpa or higher, and the bonding force with the cemented carbide substrate is greater than 130N. The tetrahedral amorphous carbon film of the top layer 4 (Ta-c structure diamond-like carbon) has a nano hardness of 40 to 80 Gpa. The tetrahedral amorphous carbon film can be prepared by physical vapor deposition, which improves the tetrahedral amorphous carbon film. The bonding force with the substrate, and because the friction coefficient of the top 4-tetrahedral amorphous carbon film can be lower than 0.1, the hardness is high and the friction coefficient is small. By depositing high hardness, low friction coefficient and good bonding force on the surface of the tool Multi-layer nano composite coating with good high temperature resistance. When processing graphite materials, aluminum alloys, carbon fiber composite materials, metal composite materials, ceramic substrates and other difficult-to-machine materials, it can significantly improve the wear resistance of the tool and greatly reduce the wear resistance. The needle breakage rate increases the service life of the tool to 4 to 20 times, and it can avoid the problems of chip accumulation and blockage of the chip flute.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement or improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. Inside.

1‧‧‧ basal layer

2‧‧‧ transition layer

3‧‧‧ core layer

4‧‧‧ top floor

In order to explain the technical solutions in the embodiments of the present invention more clearly, the drawings used in the embodiments are briefly introduced below. Obviously, the drawings in the following description are just some embodiments of the present invention. Those of ordinary skill in the art can obtain other schemes according to these schemes without paying progressive labor.

FIG. 1 is an enlarged schematic plan view of a cutter composite coating according to an embodiment of the present invention.

FIG. 2 is a Raman spectrum analysis diagram of a tetrahedral amorphous carbon film layer in a tool composite coating according to an embodiment of the present invention.

FIG. 3 is a graph showing the change of the nano-hardness of the tetrahedral amorphous carbon film layer in the tool composite coating provided by the embodiment of the present invention as a function of the depth of indentation.

Claims (10)

A tool composite coating includes a base layer coated on the tool body and a top layer located on the outermost side. The base layer is a diamond layer or a cubic boron nitride layer. The thickness of the base layer is 1 to 40 μm. It is a tetrahedral amorphous carbon film layer with a thickness of 0.01 to 15 μm. The tool composite coating according to item 1 of the patent application scope, wherein at least one intermediate layer is further provided between the base layer and the top layer, and the intermediate layer includes a transition layer and any one of a core layer, or The intermediate layer includes the transition layer and the core layer that are laminated; the transition layer is a Me layer and has a thickness of 0.01 to 10 μm, the core layer is a MeX layer and has a thickness of 0.01 to 15 μm, where Me represents aluminum (Al), titanium (Ti), chromium (Cr), vanadium (V), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zr), and non-metallic element Si At least one, X represents one or two or three of nitrogen (N), carbon (C), and boron (B). A tool includes a tool base, and a part or all of the surface of the tool base is provided with a tool composite coating as described in item 1 or 2 of the patent application scope. A method for preparing a tool composite coating includes the following steps: (1) preparing a base layer: placing a tool base in a CVD device, and forming the base layer on the surface of the tool base by the CVD device to obtain a first layer; Semi-finished product, the base layer is a diamond layer or a cubic boron nitride layer; (2) preparing a tetrahedral amorphous carbon film layer: placing the tool base with the base layer in a physical vapor phase device to form the outermost layer Tetrahedral amorphous carbon film layer. The method for preparing a tool composite coating according to item 4 of the patent application scope, wherein after the base layer is prepared and before the tetrahedral amorphous carbon film layer is formed, the method further includes at least one of the following two steps: Steps: (1) Preparation of a transition layer: Put the first semi-finished product into a PVD composite coating equipment, turn on the metal vapor vacuum arc ion source, perform Me ion implantation, Me ions are implanted on the surface of the first semi-finished product, and borrow An arc transition layer is deposited on the surface of the first semi-finished product by arc ion plating technology. Me represents at least one of Al, Ti, Cr, V, Mn, Fe, Co, Ni, Cu, Zr, and non-metal element Si. The second semi-finished product; (2) Preparation of a core layer: Put the second semi-finished product into an arc ion plating equipment, and pass in a gas containing at least one element of N, C, and B. The target material used in the arc ion plating equipment is a Me target. Material, the MeX core layer is formed on the transition layer by arc ion plating technology, and a third semi-finished product is obtained. X represents one or two or three of N, C, and B. The method for preparing a tool composite coating according to item 5 of the scope of patent application, wherein the transition layer is a Me layer and the thickness is 0.01 to 10 μm; the core layer is a MeX layer and the thickness is 0.01 to 15 μm; the tetrahedron is not The thickness of the crystalline carbon film layer is 0.01 to 15 μm. The method for preparing a tool composite coating according to item 5 of the application, wherein the base layer is a diamond layer or a cubic boron nitride layer; the thickness of the base layer is 4 to 20 μm; the transition layer is a Me layer; The thickness is 0.1 to 3 μm; the thickness of the core layer is 0.1 to 5 μm, and the thickness of the tetrahedral amorphous carbon film layer is 0.05 to 5 μm. The method for preparing a knife composite coating according to item 4 of the scope of the patent application, wherein in the step of preparing the base layer, the temperature of the hot wire in the CVD equipment is 2000-2400 ° C, and the pressure in the growth chamber is 1.5- 10Kpa, the flow rate of the reaction source gas is 150-320 sccm, the surface temperature of the substrate of the tool is 600-1000 ° C, and the growth time of the substrate layer is 5-20 hours. The method for preparing a tool composite coating according to item 5 of the scope of the patent application, wherein in the step of preparing the core layer, a gas containing at least one element of N, C, and B is passed; the flow rate of the gas is 50 to 500sccm, the arc current of the arc ion plating is 50 to 100A, the peak value of the pulse bias is -100 to -500 V, and the duty ratio is 10% to 80%. The method for preparing a tool composite coating according to item 5 of the scope of the patent application, wherein in the step of preparing the core layer, the arc current of the arc ion plating is 50 to 100 A, and the peak value of the pulse bias is -100 to -500 V. Air ratio is 10% to 80%.