Cubic boron nitride thin film structure, cutting tool and manufacturing method and equipment of cubic boron nitride thin film structure

Abstract

The invention relates to a thin film structure, a cubic boron nitride thin film structure, a cutting tool and a manufacturing method and equipment thereof. The thin film structure comprises a preliminary bonding layer-intermediate bonding layer-NCD; wherein the primary bonding layer comprises one of CrN and TiN; the intermediate bonding layer comprises at least one of an oxide film and a nitrogen-oxygen film. The preliminary bonding layer such as chromium nitride or titanium nitride is matched with the middle bonding layer and then is combined with the nano polycrystalline diamond, so that a film formed by the nano polycrystalline diamond cannot be influenced by a cobalt element on the surface of a related tool such as a hard alloy on the premise of having the hardness of the nano polycrystalline diamond; therefore, the cobalt element on the surface of the hard alloy does not need to be removed, the process that the cobalt element on the surface of the hard alloy is removed through chemical liquid medicine is avoided on the premise that the smoothness of the surface of the tool is kept, and the method has the advantages of being simple in procedure and small in pollution.

Description

Technical Field

[0001] The present application relates to the field of thin film processing, and in particular to thin film structures, cubic boron nitride thin film structures, cutting tools, and methods and equipment for manufacturing the same. Background Art

[0002] The surface of cutting tools, such as knives, usually needs to be deposited with a hard film. Whether the film can be used in cutting depends on whether the film is firmly bonded to the cutting tool substrate. A film that is not firmly bonded has no practical value. The substrates of cutting tools are mostly high-speed steel and cemented carbide. If nano-polycrystalline diamond (NCD) is deposited directly, the carbon atoms of nano-polycrystalline diamond and the iron atoms of high-speed steel, or the cobalt atoms in cemented carbide, will react chemically at high temperatures, decomposing the structure of diamond and eventually causing the nano-polycrystalline diamond film to fail.

[0003] The traditional method is to first use chemical liquid to remove the cobalt element on the surface of the tool. The cobalt element is the bonding material of the tungsten carbide in the cemented carbide on the surface of the tool, and then deposit the nano-polycrystalline diamond film. For example, Murakami's Solution uses 10g K3(CN)6+10g KOH+100mL H2O for 10 minutes, and then uses Caro's acid, including 3mL H2SO4 (96%) + 88mL H2O2 (30%) for 10 seconds to remove the cobalt element on the surface of the cemented carbide. This is done to prevent the presence of cobalt from causing carbon to form an SP2 graphite structure, which makes it impossible to form an SP3 diamond structure.

[0004] However, this approach inevitably causes the tool surface to be rough, which directly affects the surface smoothness after the nano-polycrystalline diamond is deposited. In addition, the process is cumbersome and causes serious chemical wastewater pollution. Summary of the invention

[0005] Based on this, it is necessary to provide a thin film structure, a cubic boron nitride thin film structure, a cutting tool, and a method and equipment for manufacturing the same.

[0006] In one embodiment, a thin film structure includes a preliminary bonding layer-intermediate bonding layer-NCD; wherein,

[0007] The preliminary bonding layer includes one of CrN and TiN;

[0008] The intermediate bonding layer includes at least one of an oxide film and an oxynitride film.

[0009] The above-mentioned thin film structure adopts a preliminary bonding layer such as chromium nitride or titanium nitride in combination with an intermediate bonding layer and then combined with nano-polycrystalline diamond. On the premise of having the hardness of nano-polycrystalline diamond, the cobalt element on the surface of related tools such as cemented carbide will not affect the thin film formed by the nano-polycrystalline diamond, so there is no need to remove the cobalt element on the surface of the cemented carbide. Furthermore, on the premise of maintaining the smoothness of the tool surface, the process of removing the cobalt element on the surface of the cemented carbide with chemical liquid is avoided. Therefore, it has the advantages of simple process and low pollution.

[0010] In one embodiment, the thin film structure further includes cBN, forming a preliminary bonding layer-intermediate bonding layer-NCD-cBN thin film.

[0011] In one embodiment, a cubic boron nitride film structure includes a preliminary bonding layer-intermediate bonding layer-NCD-cBN; wherein,

[0012] The preliminary bonding layer includes one of CrN and TiN;

[0013] The intermediate bonding layer includes at least one of an oxide film and an oxynitride film.

[0014] In one embodiment, the intermediate bonding layer includes at least one of AlCrON, AlCrO and AlCrSiON.

[0015] In one embodiment, a cutting tool includes a cutting tool substrate and the thin film structure described in any embodiment, wherein the thin film structure is disposed on the cutting tool substrate.

[0016] In one embodiment, a method for manufacturing a cutting tool comprises the steps of:

[0017] Providing cutting tool substrates;

[0018] Forming a preliminary bonding layer on the cutting tool substrate by arc evaporation; wherein the preliminary bonding layer comprises one of CrN and TiN;

[0019] An intermediate bonding layer is formed on the preliminary bonding layer by arc evaporation; wherein the intermediate bonding layer comprises at least one of an oxide film and an oxynitride film;

[0020] A nanometer polycrystalline diamond film layer is formed on the intermediate bonding layer by a microwave chemical deposition method.

[0021] In one embodiment, the manufacturing method of the cutting tool further includes the steps of: forming a cubic boron nitride film layer on the nano-polycrystalline diamond film layer using a high-power pulsed magnetron sputtering method; and or, the intermediate bonding layer includes at least one of AlCrON, AlCrO and AlCrSiON.

[0022] In one of the embodiments, the method for manufacturing the cutting tool further comprises the step of: cleaning the cutting tool substrate by a plasma method.

[0023] In one embodiment, a cutting tool manufacturing apparatus includes a vacuum furnace, a heating device, a vacuum device, a high-power pulse sputtering device, an arc evaporation device, a microwave generating device, a pulse bias device, a gas flow control device, and a temperature control device;

[0024] The heating device, the vacuum device, the high-power pulse sputtering device, the arc evaporation device, the microwave generating device, the pulse bias device, the gas flow control device and the temperature control device are at least partially arranged in the inner cavity of the vacuum furnace;

[0025] The heating device is used to heat the inner cavity;

[0026] The vacuum device is used to evacuate the inner cavity and detect the vacuum degree;

[0027] The target material of the high-power pulse sputtering device, the target material of the arc evaporation device and the output end of the microwave generating device are arranged in the inner cavity;

[0028] The pulse bias device is electrically connected to the high-power pulse sputtering device, the arc evaporation device and the microwave generating device respectively;

[0029] The gas flow control device is used to input gas into the inner cavity;

[0030] The temperature control device is electrically connected to the heating device and is used to control the temperature of the inner cavity.

[0031] In one embodiment, the arc evaporation device is provided with one or two arc targets for depositing a preliminary bonding layer and an intermediate bonding layer; wherein the preliminary bonding layer comprises one of CrN and TiN, and the intermediate bonding layer comprises at least one of an oxide film and a nitride oxide film;

[0032] The microwave generating device is provided with at least one microwave deriver for depositing a nano-polycrystalline diamond film;

[0033] The high-power pulse sputtering device is provided with one or two high-power pulse sputtering targets for depositing cubic boron nitride films.

[0034] In one embodiment, the inner wall of the vacuum furnace is provided with a cold water pipeline; or,

[0035] The arc evaporation device is provided with an arc pure chromium pure titanium target and an arc aluminum silicon target; or,

[0036] The high-power pulse sputtering device is provided with a sputtering pure boron target; or,

[0037] The temperature control device is provided with a furnace temperature control system and a cold water control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] FIG. 1 is a schematic flow chart of an embodiment of a method for manufacturing a cutting tool described in the present application.

[0040] FIG. 2 is a schematic flow chart of another embodiment of the method for manufacturing a cutting tool described in the present application.

[0041] FIG3 is a schematic structural diagram of an embodiment of a manufacturing device for cutting tools described in the present application.

[0042] FIG. 4 is a schematic diagram of another state of the embodiment shown in FIG. 3 .

[0043] FIG5 is a schematic structural diagram of another embodiment of the manufacturing equipment for the cutting tool described in the present application.

[0044] FIG. 6 is a schematic diagram of the embodiment shown in FIG. 5 in another direction.

[0045] FIG. 7 is a schematic diagram of another state of the embodiment shown in FIG. 6 .

[0046] FIG. 8 is a perspective schematic diagram of the embodiment shown in FIG. 6 .

[0047] FIG. 9 is another schematic diagram of identification of the embodiment shown in FIG. 5 .

[0048] FIG. 10 is an exploded schematic diagram of the embodiment shown in FIG. 9 .

[0049] FIG. 11 is an electron microscope inspection image of an embodiment of the cutting tool described in the present application.

[0050] FIG. 12 is a detection diagram of a nanohardness tester of the embodiment shown in FIG. 11 .

[0051] FIG. 13 is an FTIR detection diagram of the embodiment shown in FIG. 11 .

[0052] Figure numerals: 1, stainless steel vacuum furnace, 2, tool fixture turntable, 3, tool fixture, 4, molecular pump and vacuum system, 5, heating tube, 6, reaction gas inlet pipe, 7, vacuum furnace door hinge, 8, furnace door, 9, arc rectangular pure chromium / titanium target, 10, arc rectangular aluminum silicon target, 11, door handle, 12, cylindrical sputtering pure boron target, 13, microwave exporter, 14, microwave guide tube, 15, microwave main guide tube, 16, microwave generator, 17, bias pulse power supply, 18, H iPIMS sputtering power supply, 19. Arc pulse power supply for target No. 9, 20. Arc pulse power supply for target No. 10, 21. PLC automation control system, 22. Panel-type industrial control computer, 23. Low-voltage cabinet housing, 24. Penning vacuum gauge, 25. Pinari vacuum gauge, 26. Gearbox, 27. Turntable motor, 28. Inner cavity, 100. Cemented carbide, 200. Transition layer, 300. Nano-polycrystalline diamond layer, 400. Cubic boron nitride layer. DETAILED DESCRIPTION

[0053] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0054] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it may be directly on the other component or there may also be a central component. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may be a central component at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in the specification of this application are for illustrative purposes only and do not represent the only implementation method.

[0055] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0056] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first feature is directly in contact with the second feature, or the first feature and the second feature are in contact indirectly through an intermediate medium. Moreover, a first feature being “above”, “above”, or “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, or “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0057] Unless otherwise defined, all technical and scientific terms used in the specification of this application have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and or" used in the specification of this application includes any and all combinations of one or more related listed items.

[0058] The present application discloses a thin film structure, a cubic boron nitride thin film structure, a cutting tool and a manufacturing method and equipment thereof, which include some or all of the technical features of the following embodiments; that is, the thin film structure, the cubic boron nitride thin film structure, the cutting tool and the manufacturing equipment thereof include some or all of the following structures. In one embodiment of the present application, a thin film structure includes a preliminary bonding layer-intermediate bonding layer-NCD; wherein the preliminary bonding layer includes one of CrN and TiN; the intermediate bonding layer includes at least one of an oxide film and a nitride oxide film. The above-mentioned thin film structure uses a preliminary bonding layer such as chromium nitride or titanium nitride in combination with an intermediate bonding layer and then combined with nano-polycrystalline diamond. On the premise of having the hardness of nano-polycrystalline diamond, the cobalt element on the surface of related tools such as cemented carbide will not affect the thin film formed by the nano-polycrystalline diamond, so there is no need to remove the cobalt element on the surface of the cemented carbide, and then on the premise of maintaining the smoothness of the tool surface, avoids the process of removing the cobalt element on the surface of the cemented carbide using chemical liquid, so it has the advantages of simple process and low pollution. 1 to 13 , the thin film structure, cutting tool, and manufacturing method and system thereof are described in detail below.

[0059] In one of the embodiments, a thin film structure includes a preliminary bonding layer-intermediate bonding layer-NCD; that is, the bottom layer is the preliminary bonding layer, the intermediate bonding layer is above the preliminary bonding layer, and the NCD is above the intermediate bonding layer; that is, the thin film structure includes a preliminary bonding layer, an intermediate bonding layer and an NCD layer stacked in sequence, and the preliminary bonding layer is used to bond or attach to a substrate. Wherein, the preliminary bonding layer includes one of chromium nitride (CrN) and titanium nitride (TiN). As an example, the CrN layer is a chromium nitride film, that is, a chromium nitride film layer, and the NCD layer is a polycrystalline diamond, that is, a nano-polycrystalline diamond film, that is, a nano-polycrystalline diamond film layer. In each embodiment, the intermediate bonding layer includes at least one of an oxide film and an oxynitride film, and the intermediate bonding layer is used to achieve bonding between the NCD film and the cutting tool substrate. Such a design, with an oxide film or an oxynitride film as an intermediate bonding layer, illustratively, with chromium nitride or titanium nitride as the preliminary bonding layer between the cutting tool and the intermediate bonding layer, is conducive to enhancing adhesion and ensuring isolation. With the oxide film or the oxynitride film as the intermediate bonding layer between the cutting tool and the polycrystalline diamond, the isolation of the nano-polycrystalline diamond film and the cutting tool is further ensured. Therefore, the film-forming process does not require chemical liquid to remove the cobalt element, nor does it require soaking diamond powder. The nano-polycrystalline diamond film, i.e., the polycrystalline diamond film, can be directly deposited thereon. Therefore, in addition to reducing the use of environmentally harmful chemical liquids, the surface smoothness of the cutting tool after coating can also be maintained.

[0060] In one of the embodiments, the intermediate bonding layer includes at least one of AlCrON, AlCrO and AlCrSiON. As an example, the intermediate bonding layer is AlCrON, AlCrO or AlCrSiON, and illustratively, the intermediate bonding layer is AlCrSiON, i.e. silicon chromium aluminum oxynitride, and the film structure includes chromium nitride-silicon chromium aluminum oxynitride-nano polycrystalline diamond. The remaining embodiments are similar and will not be described in detail. In each embodiment, the film structure includes a multilayer film, so it can also be called a multilayer film, a multilayer film structure or a composite film layer. Due to the design of CrN or TiN combined with the intermediate bonding layer, the cobalt element on the surface of the cemented carbide will not affect the film formed by the nano-polycrystalline diamond, so that the surface of the cemented carbide can be combined with the film formed by the nano-polycrystalline diamond through CrN or TiN combined with the intermediate bonding layer without removing the cobalt element on the surface of the cemented carbide, so as to have the hardness of nanocrystalline diamond.

[0061] On the basis of the above embodiments, a cBN film can be additionally provided on the NCD film. Specifically, in one of the embodiments, the film structure also includes cBN to form a CrN-intermediate bonding layer-NCD-cBN film. Alternatively, in one of the embodiments, a cubic boron nitride film structure includes a preliminary bonding layer CrN-intermediate bonding layer-NCD-cBN; wherein the preliminary bonding layer includes one of CrN and TiN; the intermediate bonding layer includes at least one of an oxide film and a nitride oxide film. In one of the embodiments, a cubic boron nitride film structure includes CrN-intermediate bonding layer-NCD-cBN to form a CrN-intermediate bonding layer-NCD-cBN film; wherein the intermediate bonding layer includes at least one of an oxide film and a nitride oxide film. In this way, in response to different product requirements, it can be considered whether an additional cBN film, i.e., a cBN film layer, is needed. Generally, the function of polycrystalline diamond film can only process non-ferrous alloys, such as aluminum, titanium, magnesium alloys, etc. Although diamond is the hardest material, its structure is composed of carbon elements, and the carbon element of diamond and iron react chemically during high-temperature processing to become Fe3C, which is equivalent to decomposing diamond, so it is impossible to process alloy steel mainly composed of iron elements. Specifically, the hardness of NCD diamond film is 100GPa, and the hardness of cBN film is 70GPa to 80GPa. They are generally considered to be the top two materials in terms of hardness. Compared with the conventional TiN and AlTiN films with a hardness of 40GPa to 45GPa, the performance is better. For example, in terms of hardness, NCD is higher than cBN, and it can even be relatively considered that NCD has the first hardness and cBN has the second hardness. Therefore, when using a cutting tool with the film structure to process non-ferrous alloys, a film structure including CrN-intermediate bonding layer-NCD can be directly used. However, since NCD is composed of carbon atoms, when a cutting tool with the above-mentioned film structure is used to process iron-containing alloys, carbon and iron will produce a chemical reaction during high-temperature processing to become cementite, i.e., iron carbide Fe3C, so alloy steel cannot be processed. cBN does not have carbon atoms, so cBN replaces NCD and becomes the hardest film that can be used to process alloy steel. For example, it can be used to cut alloy steel. Therefore, when processing alloy steel, a cutting tool with a cBN film can be selected.

[0062] For the above-mentioned embodiments with or without cBN, the same device can manufacture two functional films, and the difference between the two functional films is whether they have cBN. The main purpose is whether the processed object is an iron-containing alloy. As mentioned above, if it is an iron-containing alloy, the film structure with cBN is adopted, and if it is a non-ferrous alloy, the film structure without cBN is adopted. The embodiment with cBN is additionally realized based on the NCD film. This is because the arrangement of cBN on the NCD can obtain stable structural characteristics. Specifically, in each embodiment of the present application, cBN is deposited on the NCD, and cBN cannot be directly deposited on the chromium nitride or the intermediate bonding layer, otherwise it will affect the structural stability of the cBN film of the product.

[0063] In one embodiment, a cutting tool comprises the thin film structure described in any embodiment. In one embodiment, a cutting tool comprises a cutting tool substrate and a thin film structure disposed on the cutting tool substrate, wherein the thin film structure is the thin film structure described in any embodiment. As an example, the thin film structure is formed on the surface of the cutting tool substrate, such as cemented carbide, to obtain the cutting tool; in a specific application, the cutting tool is a cutting tool, such as a blade, etc., used to achieve a cutting function, such as processing an alloy; as an example, the cutting tool substrate is high-speed steel or cemented carbide, etc. As mentioned above, when processing non-ferrous alloys, the cutting tool may adopt the thin film structure without cBN, that is, the outermost layer of the cutting tool and its thin film structure is an NCD layer; when processing ferrous alloys, the cutting tool may adopt the thin film structure with cBN, that is, the outermost layer of the cutting tool and its thin film structure is a cBN layer. Moreover, under the premise of ensuring the hardness of the outer layer of the cutting tool, the design of chromium nitride and the intermediate bonding layer ensures that the cobalt element on the surface of the cutting tool substrate will not affect the thin film formed by the nanocrystalline diamond, so there is no need to remove the cobalt element on the surface of the cemented carbide. Under the premise of maintaining the smoothness of the tool surface, the process of removing the cobalt element on the surface of the cemented carbide using chemical solutions is avoided.

[0064] In one embodiment, a method for manufacturing a cutting tool is shown in FIG1 , and includes the following steps: providing a cutting tool substrate; forming a preliminary bonding layer such as a chromium nitride film layer on the cutting tool substrate by arc evaporation; wherein the preliminary bonding layer includes one of CrN and TiN; that is, the preliminary bonding layer is CrN or TiN; forming an intermediate bonding layer on the chromium nitride film layer by arc evaporation; wherein the intermediate bonding layer includes at least one of an oxide film and an oxynitride film; forming a nano-polycrystalline diamond film layer on the intermediate bonding layer by microwave chemical deposition. Exemplarily, the method for manufacturing a cutting tool is used to prepare the cutting tool described in any embodiment and the film structure described in any embodiment.

[0065] In one of the embodiments, the manufacturing method of the cutting tool further includes the step of: forming a cubic boron nitride film layer on the nano-polycrystalline diamond film layer by high-power pulsed magnetron sputtering. As an example, a manufacturing method of a cutting tool is shown in Figure 2, which includes the steps of: providing a cutting tool substrate; forming a preliminary bonding layer on the cutting tool substrate by arc evaporation; wherein the preliminary bonding layer includes one of CrN and TiN; forming an intermediate bonding layer on the chromium nitride film layer by arc evaporation; wherein the intermediate bonding layer includes at least one of an oxide film and a nitride oxide film; forming a nano-polycrystalline diamond film layer on the intermediate bonding layer by microwave chemical deposition; forming a cubic boron nitride film layer on the nano-polycrystalline diamond film layer by high-power pulsed magnetron sputtering. The rest of the embodiments are similar and will not be described in detail. For example, as a comparison, the traditional method for depositing cubic boron nitride uses ECR electron cyclotron resonance, which produces low plasma energy and long deposition time, and is only suitable for laboratory environments and not suitable for industrial use. The present application adopts the principle of high-power pulse sputtering to produce high-energy boron nitrogen plasma that can be used for industrial purposes. Compared with the traditional ECR electron cyclotron resonance method, the plasma density of the two differs by 10 times. Therefore, under the same deposition conditions, assuming that ECR deposition takes 4 hours, the HiPIMS deposition time adopted in the present application only takes 1 hour; this greatly improves the production efficiency of cutting tools. The above design adopts three plasma deposition methods, including arc evaporation method, high-power pulse magnetron sputtering method and microwave chemical deposition method. In order to combine chromium nitride and oxide film or oxynitride film, an arc plasma method is used for manufacturing; polycrystalline diamond adopts microwave chemical vapor deposition, and does not adopt the hot wire method commonly used in industry to avoid too high temperature, such as a deposition temperature of more than 1,000 degrees Celsius affecting the diamond deposition substrate, such as the diamond deposition substrate including high-speed steel, chromium nitride film and intermediate bonding layer.

[0066] In one embodiment, the manufacturing method of the cutting tool further comprises the step of: forming a cubic boron nitride film layer on the nano-polycrystalline diamond film layer by a high-power pulsed magnetron sputtering method, and the intermediate bonding layer comprises at least one of AlCrON, AlCrO and AlCrSiON. The rest of the embodiments are similar and will not be described in detail.

[0067] Exemplarily, before forming a chromium nitride film layer on the cutting tool substrate by arc evaporation, the method for manufacturing the cutting tool further includes the step of: pre-starting a vacuum furnace. In one embodiment, the method for manufacturing the cutting tool further includes the step of: cleaning the cutting tool substrate by a plasma method. That is, before forming a thin film, a plasma method is first used to clean the cutting tool substrate, that is, the plated workpiece. As an example, after pre-starting the vacuum furnace, the method for manufacturing the cutting tool further includes the step of: cleaning the cutting tool substrate by a plasma method. Exemplarily, the plasma method is used to clean the cutting tool substrate, including glow cleaning and ion cleaning.

[0068] Using the above-mentioned manufacturing method of the cutting tool, the present application also provides a manufacturing device for the cutting tool, which is implemented by the manufacturing method of the cutting tool described in any embodiment. Since the manufacturing method of the cutting tool described in any embodiment is adopted, the manufacturing device for the cutting tool also has the beneficial technical effects of the manufacturing device for the cutting tool, which will not be described in detail here.

[0069] In one embodiment, a cutting tool manufacturing device includes a vacuum furnace, a heating device, a vacuum device, a high-power pulse sputtering device, an arc evaporation device, a microwave generating device, a pulse bias device, a gas flow control device and a temperature control device; the heating device, the vacuum device, the high-power pulse sputtering device, the arc evaporation device, the microwave generating device, the pulse bias device, the gas flow control device and the temperature control device are at least partially arranged in the inner cavity of the vacuum furnace; the heating device is used to heat the inner cavity; the vacuum device is used to evacuate the inner cavity and detect the vacuum degree; the target materials of the high-power pulse sputtering device, the arc evaporation device and the microwave generating device are arranged in the inner cavity; the pulse bias device is electrically connected to the high-power pulse sputtering device, the arc evaporation device and the microwave generating device respectively; the gas flow control device is used to input gas into the inner cavity; the temperature control device is electrically connected to the heating device for controlling the temperature of the inner cavity. It should be noted that the vacuum furnace, the heating device, the vacuum device, the high-power pulse sputtering device, the arc evaporation device, the microwave generating device, the pulse bias device, the gas flow control device and the temperature control device, etc. can all be purchased directly from the market or made by yourself. The embodiments of this application do not involve specific improvements to these structures.

[0070] In one embodiment, the arc evaporation device is provided with one or two arc targets for depositing a chromium nitride film and an intermediate bonding layer; wherein the intermediate bonding layer includes at least one of an oxide film and an oxynitride film; the microwave generating device is provided with at least one microwave exporter, and the microwave generating device or its microwave generator generates plasma on a pure reaction gas through microwaves, that is, the gas is plasmatized through the microwave generator, for depositing a nano-polycrystalline diamond film; the high-power pulse sputtering device is provided with one or two high-power pulse sputtering targets for depositing a cubic boron nitride film.

[0071] As an example, the manufacturing equipment of the cutting tool is provided with four targets, specifically including: an arc target, using an arc evaporation source, the evaporation material is AlCr, and the atomic ratio of the two is 70:30; or the evaporation material is AlCrSi, and the atomic ratio of the three is 65:25:5. A group of microwave generators for depositing polycrystalline diamond. The other two are equipped with high-power pulsed sputtering targets for depositing cubic boron nitride films. For example, target 1 is Cr or Ti, target 2 is AlCr or AlCrSi, and target 3 and target 4 are both pure boron.

[0072] Alternatively, the manufacturing equipment of the cutting tool is provided with five targets, specifically including: two arc targets, using an arc evaporation source. A group of microwave generators for depositing polycrystalline diamond. The other two are equipped with high-power pulse sputtering targets for depositing cubic boron nitride films on the bonding layer and the diamond layer. For example, target 1 is Cr or Ti, target 2 and target 3 are at least one of AlCr and AlCrSi, and target 4 and target 5 are both pure boron. For example, target 2 and target 3 are both AlCr or both AlCrSi.

[0073] In one embodiment, the inner wall of the vacuum furnace is provided with a cold water pipeline; as an example, the vacuum furnace is embedded or protruded with a water pipe on its inner wall as the cold water pipeline, or the vacuum furnace is provided with an interlayer on its inner wall, and the interlayer is used as the cold water pipeline. In one embodiment, the temperature control device is provided with a furnace temperature control system and a cold water control system. As an example, the manufacturing equipment of the cutting tool is provided with a stainless steel vacuum furnace, a high-temperature heating tube, a vacuum pumping system and a vacuum detection instrument, a high-power pulse sputtering power supply, an arc power supply, a microwave generator power supply, a pulse bias power supply, a gas flow control system, a furnace temperature control system and a cold water control system, and finally achieves the goal of industrial mass production of cubic boron nitride.

[0074] In one embodiment, the arc evaporation device is provided with an arc pure chromium pure titanium target and an arc aluminum silicon target; and / or, the high-power pulse sputtering device is provided with a sputtering pure boron target. As an example, the arc evaporation device is provided with an arc rectangular pure chromium pure titanium target and an arc rectangular aluminum silicon target; in one embodiment, the high-power pulse sputtering device is provided with a cylindrical sputtering pure boron target; illustratively, the boron target material is a semiconductor material and is an insulator at room temperature, so it needs to be heated to more than 400 degrees to have sufficiently active electrons to achieve sputtering. When the sputtering reaction occurs, the temperature is lowered to produce sufficiently active electrons. This is because when the current is generated, the current will also generate temperature when it moves on the surface of the material, so there is no need to use an additional heating tube to increase its temperature. In addition, the resistivity of pure boron crystal at room temperature is about 1000ohm·cm to 100000ohm·cm, but because boron is a semiconductor material, its resistance value decreases when the temperature is increased, and when it exceeds 300 degrees Celsius, it is less than 200ohm·cm. This resistance value range is sufficient to generate current on the surface of pure boron. Therefore, the surface temperature of the cylindrical sputtering pure boron target can also be detected by the temperature control device or the circuit control device. Exemplarily, the present embodiment adopts a cylindrical sputtering pure boron target, and provides a rotating cylindrical sputtering target material when in use. Generally, the utilization rate of rectangular target materials is 30%, but the utilization rate of cylindrical target materials is as high as 85%. Therefore, it is beneficial to improve the utilization rate of target materials and adapt to the relatively expensive price of pure boron materials. In other embodiments, rectangular sputtering pure boron targets or sputtering pure boron targets of other shapes may also be used.

[0075] Based on the manufacturing equipment of the cutting tool, in one embodiment, the present application also provides a manufacturing method of the cutting tool, which is implemented based on the manufacturing equipment of the cutting tool in any embodiment, that is, the manufacturing method of the cutting tool adopts the manufacturing equipment of the cutting tool in any embodiment. Since the manufacturing equipment of the cutting tool in any embodiment is adopted, the manufacturing method of the cutting tool also has the beneficial technical effects of the manufacturing equipment of the cutting tool, which will not be elaborated here.

[0076] The following example illustrates the specific implementation of the manufacturing equipment of the cutting tool. In one embodiment, as shown in FIG3 and FIG4, the manufacturing equipment of the cutting tool includes a stainless steel vacuum furnace 1 with an inner wall cooling water system as the vacuum furnace, and a tool fixture turntable 2 and a tool fixture 3 are provided in the stainless steel vacuum furnace 1. The tool fixture 3 is arranged on the tool fixture turntable 2 and is used to fix the tool to be processed as the cutting tool substrate; the tool fixture 3 rotates as the tool fixture turntable 2 rotates.

[0077] The manufacturing equipment of the cutting tool is also provided with a vacuum furnace door hinge 7, two furnace doors 8 and a door opening handle 11, so as to cooperate with the stainless steel vacuum furnace 1 to realize the opening and closing of the door.

[0078] 5 and 6 , the manufacturing equipment for the cutting tool further includes a molecular pump and a vacuum system 4 as the vacuum device. The molecular pump and the vacuum system 4 are located outside the stainless steel vacuum furnace 1 and are connected to the stainless steel vacuum furnace 1 . The molecular pump and the vacuum system 4 are used to evacuate the inner cavity 28 of the stainless steel vacuum furnace 1 .

[0079] 9 and 10 , the cutting tool manufacturing equipment further includes four groups of heating tubes 5 as the heating devices, which are arranged in the inner cavity 28 of the stainless steel vacuum furnace 1 for heating the environment of the inner cavity 28 of the stainless steel vacuum furnace 1 .

[0080] The cutting tool manufacturing equipment also includes four groups of reaction gas inlet pipes 6 as the gas flow control devices. The four groups of reaction gas inlet pipes 6 are connected to the inner cavity 28 of the stainless steel vacuum furnace 1 and are used to input gas into the inner cavity 28.

[0081] In conjunction with Figures 7 and 8, the manufacturing equipment for the cutting tool further includes an arc rectangular pure chromium / titanium target 9, an arc rectangular aluminum silicon target 10 and four cylindrical sputtering pure boron targets 12 arranged in the inner cavity 28 of the stainless steel vacuum furnace 1, which are used to form corresponding deposits in the arc evaporation method and the high-power pulse magnetron sputtering method, respectively. The arc rectangular pure chromium / titanium target 9 and the arc rectangular aluminum silicon target 10 are part of the arc evaporation device, and the cylindrical sputtering pure boron target 12 is part of the high-power pulse sputtering device.

[0082] Specifically, the manufacturing equipment of the cutting tool also includes an arc evaporation device, which includes an arc rectangular pure chromium / titanium target 9 and an arc rectangular aluminum silicon target 10, and also includes a first arc pulse power supply 19 and a second arc pulse power supply 20 arranged outside the stainless steel vacuum furnace 1, the first arc pulse power supply 19 supplies power to the arc rectangular pure chromium / titanium target 9, and the second arc pulse power supply 20 supplies power to the arc rectangular aluminum silicon target 10.

[0083] The manufacturing equipment of the cutting tool further includes a microwave generating device, which includes a microwave exporter 13, a microwave guide tube 14, a microwave main conduit 15 and a microwave generator 16 connected in sequence, wherein the microwave head 13, the microwave guide tube 14 and the microwave main conduit 15 are arranged in the inner cavity 28 of the stainless steel vacuum furnace 1. The microwave exporter 13, the microwave guide tube 14, the microwave main conduit 15 and the microwave generator 16 plasmatize the gas.

[0084] The manufacturing equipment of the cutting tool further comprises a pulse bias device, and the pulse bias device comprises a bias pulse power supply 17 arranged outside the stainless steel vacuum furnace 1 .

[0085] The manufacturing equipment of the cutting tool further comprises a high-power pulse sputtering device, and the high-power pulse sputtering device comprises two HiPIMS sputtering power supplies 18 arranged outside the stainless steel vacuum furnace 1 .

[0086] The manufacturing equipment of the cutting tool further includes a PLC automatic control system 21 as the temperature control device, and the PLC automatic control system 21 is arranged outside the stainless steel vacuum furnace 1 .

[0087] The manufacturing equipment of the cutting tool also includes a panel-type industrial control computer 22, which is electrically connected to the tool fixture turntable 2, the molecular pump and vacuum system 4, the heating tube 5, the microwave generator 16, the bias pulse power supply 17, the HiPIMS sputtering power supply 18, the first arc pulse power supply 19, the second arc pulse power supply 20 and the PLC automatic control system 21. The panel-type industrial control computer 22 serves as the master controller of the manufacturing equipment of the cutting tool to realize the specific process control of the manufacturing method of the cutting tool.

[0088] The manufacturing equipment of the cutting tool also includes a weak-current cabinet housing 23, in which the stainless steel vacuum furnace 1, microwave generator 16, bias pulse power supply 17, HiPIMS sputtering power supply 18, first arc pulse power supply 19, second arc pulse power supply 20 and PLC automatic control system 21 are arranged, the molecular pump and vacuum system 4 are arranged outside the weak-current cabinet housing 23, the panel-type industrial control computer 22 is arranged on the weak-current cabinet housing 23, the furnace door 8 of the stainless steel vacuum furnace 1 is arranged on the weak-current cabinet housing 23, and the stainless steel vacuum furnace 1 can be directly opened or closed relative to the external environment by opening and closing the furnace door 8, without the need to additionally open and close other structures of the weak-current cabinet housing 23.

[0089] The manufacturing equipment of the cutting tool also includes a vacuum gauge, a gearbox 26 and a turntable motor 27. The gearbox 26 and the turntable motor 27 are both arranged outside the weak-current cabinet housing 23. The turntable motor 27 drives and connects to the gearbox 26. The output rod of the gearbox 26 passes through the weak-current cabinet housing 23 and is connected to the tool fixture turntable 2.

[0090] The vacuum gauge includes a Penning vacuum gauge 24 and a Pinari vacuum gauge 25 . The Penning vacuum gauge 24 and the Pinari vacuum gauge 25 have a portion located outside the weak-current cabinet housing 23 and a portion located in the inner cavity 28 of the stainless steel vacuum furnace 1 .

[0091] The prepared cutting tool was inspected by electron microscope, and the obtained photo is shown in FIG11 , wherein the cutting tool substrate is cemented carbide 100, on which there is a relatively uniform transition layer 200, and the transition layer 200 is a composite layer of CrN and AlCrSiON; in other embodiments, the transition layer 200 can also be a composite layer of TiN, AlCrON and AlCrO. On the transition layer 200 is a nano-polycrystalline diamond layer 300, i.e., an NCD layer or an NCD thin film layer, and on the nano-polycrystalline diamond layer 300 is a cubic boron nitride layer 400, i.e., a cBN layer or a cBN thin film layer.

[0092] The cutting tool described in the above embodiment is tested for nanohardness, and the results are shown in Figure 12, which shows the relationship between force and indentation depth. The circled position in the figure shows that plastic deformation occurs at that position. As can be seen from the figure, as the pressure increases from 0 to 10 millinewtons, the indentation slowly grows to more than 90 nanometers but less than 100 nanometers. From this, the nanohardness value of the cutting tool can be calculated, and the hardness can reach 70GPa to 80GPa. It can be seen that the hardness of the cutting tool and its film structure described in this application can meet the design requirements.

[0093] The cutting tool described in the above embodiment is subjected to Fourier transform infrared absorption spectroscopy detection, and the result obtained is shown in FIG13 , in which the characteristic wavelength of the cubic boron nitride film structure is clearly detected.

[0094] The following is an example to illustrate the specific implementation of the manufacturing equipment and method of the cutting tool.

[0095] Exemplarily, the conditions for pre-starting the vacuum furnace include:

[0096] Furnace temperature: greater than 400°C; ideal furnace temperature greater than 450°C;

[0097] Vacuum degree: less than 9×10 -5 mbar ideal vacuum degree is less than 5×10 -5 mbar;

[0098] After the above conditions are met, the subsequent process can be started.

[0099] Exemplarily, the conditions for glow cleaning include:

[0100] Gas: pure argon Ar, purity not less than 99.999%;

[0101] Furnace chamber pressure range: 8×10 -3 mbar to 5×10 -2 mbar;

[0102] Bias power supply: low voltage 300V to 350V; high voltage 650V to 750V;

[0103] Cleaning time: depends on the number of workpieces and the complexity of their appearance. Generally speaking, the total time is about half an hour.

[0104] Exemplarily, the conditions for ion cleaning include:

[0105] Gas: pure argon Ar, purity not less than 99.999%;

[0106] Furnace chamber pressure: 5×10 -3 mbar;

[0107] Bias power supply: High voltage: 600V to 750V;

[0108] Chromium / titanium target: current is 100A to 180A, pulse is 5Hz to 1000Hz;

[0109] Cleaning time: depends on the number of workpieces and the complexity of their appearance. Generally speaking, the total time is about 15 minutes;

[0110] Turntable speed: 6rpm to 8rpm.

[0111] In this way, the metal ion cleaning function can be achieved.

[0112] Under the premise of the above preparation process, the CrN film is used as a basic bonding layer to achieve the bonding between the film and the substrate, and its preparation is described as follows.

[0113] When the ions are cleaned, the chromium / titanium target continues to operate, and at this time, nitrogen with a purity of not less than 99.999% is turned on and argon is turned off;

[0114] The nitrogen pressure is 5×10 -3 mbar to 1×10 -2 mbar range; turntable speed should be greater than 6rpm;

[0115] Bias power supply: 800V to 180V range;

[0116] Furnace temperature: greater than 400°C;

[0117] The deposition time depends on the size of the workpiece, and the general deposition thickness is around 0.2 microns.

[0118] Turntable speed: 6rpm to 8pm.

[0119] Under the premise of the above preparation process, the intermediate bonding layer: Cr / Ti+AlSiON layer, or Cr / Ti+AlCON layer, is prepared as follows.

[0120] The chromium / titanium target continued to operate, the current was increased to 150A to 250A, the current pulse was in the range of 5Hz to 1000Hz, and the nitrogen pressure was maintained at 1×10-2 mbar to 7×10 -2 mbar range.

[0121] At this time, the AlSi target is started; wherein Al:Si is 88:12 to 82:18; for example, Al:Si is 88:12 or 82:18 atomic ratio, depending on the workpiece shape and film requirements, the current is in the range of 150A to 250A, and the current pulse is in the range of 5Hz to 1000Hz.

[0122] At this time, a flow controller is used to control the oxygen flow rate, starting from 5 sccm and increasing by 1 sccm per minute until the pressure ratio of oxygen to nitrogen is O2:N2=40%:60%.

[0123] A transition layer film is formed as an intermediate bonding layer, and the thickness is controlled to be about 0.3 micron to 0.5 micron. The bias voltage is controlled to be in the range of 30V to 150V.

[0124] Furnace temperature: greater than 400℃.

[0125] Turntable speed: 6rpm to 8rpm.

[0126] Based on the above preparation process, the preparation of the polycrystalline nano-diamond layer, that is, the nano-polycrystalline diamond film layer, is described as follows.

[0127] After the intermediate bonding layer is completed, the working state of manufacturing the intermediate bonding layer is maintained, CH4 gas with a purity of not less than 99.999% is turned on, and its flow rate is controlled to be 5 sccm to 10 sccm, and maintained for 5 minutes to 15 minutes.

[0128] Then turn off the arc power supply, N2 and O2 gases, and turn on H2 with a purity of not less than 99.999% and CO2 with a purity of not less than 99.999%, keeping the ratio of H2:CH4:CO2 = (80% to 90%): (5% to 10%): (5% to 10%), and the total gas pressure at 8×10 -3 mbar to 8×10 -2 mbar range.

[0129] Then start the microwave generator and adjust the output power depending on the number of workpieces and deposition rate, generally between 500W and 5kW or higher.

[0130] The bias power supply is in the range of 50V to 200V; the furnace temperature is greater than 400°C; the turntable speed is 6rpm to 8rpm.

[0131] The thickness of the polycrystalline nano-diamond layer is 0.3 microns to 0.5 microns.

[0132] Based on the above preparation process, the preparation of the cubic boron nitride layer is described as follows.

[0133] Stop the process of manufacturing polycrystalline nanodiamond layer, keep the furnace temperature above 450℃ and stop the cooling system of pure boron target for about 5 minutes, depending on the surface temperature of the target material, and then wait until the vacuum degree reaches 9×10 -5 mbar or lower, open N2 until the furnace chamber pressure is 5×10 -3 mbar to 8×10 -2 mbar range, when the pure boron target has sufficient temperature to become a conductor.

[0134] Then, the cooling system of the pure boron target is started, and the bias power supply is started and adjusted to a range of 400V to 600V.

[0135] Then, turn on the argon and nitrogen gases and set the furnace pressure at 8×10 -3 Up to 5×10 -2 mbar. Then turn on the HiPIMS power supply and set the argon output in the range of 5sccm to 30sccm until the sputtering effect is achieved.

[0136] The power mode is adjusted to the pulse range of 250kHz to 350kHz, outputting an asymmetric square wave to neutralize the target material accumulated voltage with reverse voltage, with a maximum output power of 5kW.

[0137] Depending on the volume of the furnace chamber, the number of workpieces and the deposition time, the deposition rate is generally adjusted to 1 micron / hour.

[0138] After sputtering occurs, the bias voltage is adjusted from a high voltage of 400V to 600V to a deposition voltage range of 50V-150V, and the turntable speed is 6rpm to 8rpm.

[0139] When the deposition thickness is reached, all processes can be stopped, but the vacuum operation continues until the furnace temperature reaches 150°C.

[0140] At this time, turn off the vacuum system, break the vacuum, open the furnace door and take out the workpiece with deposited cubic boron nitride.

[0141] At this point, the preparation of the cutting tool is completed.

[0142] It should be noted that other embodiments of the present application also include thin film structures, cubic boron nitride thin film structures, cutting tools, and methods and equipment for manufacturing the same, which are implemented by combining the technical features in the above embodiments.

[0143] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0144] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of patent protection of the present application shall be subject to the attached claims.

Claims

1. A thin film structure, characterized in that: It includes a preliminary bonding layer-an intermediate bonding layer-NCD; wherein, The preliminary bonding layer includes one of CrN and TiN; The intermediate bonding layer includes at least one of an oxide film and an oxynitride film.

2. A cubic boron nitride thin film structure, characterized in that: It includes a preliminary bonding layer-an intermediate bonding layer-NCD-cBN; wherein, The preliminary bonding layer includes one of CrN and TiN; The intermediate bonding layer includes at least one of an oxide film and an oxynitride film.

3. The cubic boron nitride thin film structure according to claim 2, characterized in that: The intermediate bonding layer includes at least one of AlCrON, AlCrO and AlCrSiON.

4. A cutting tool, characterized in that: The invention comprises a cutting tool substrate and the thin film structure according to any one of claims 1 to 3, wherein the thin film structure is arranged on the cutting tool substrate.

5. A method for manufacturing a cutting tool, characterized in that: Includes steps: Providing cutting tool substrates; Forming a preliminary bonding layer on the cutting tool substrate by arc evaporation; wherein the preliminary bonding layer comprises one of CrN and TiN; An intermediate bonding layer is formed on the preliminary bonding layer by arc evaporation; wherein the intermediate bonding layer comprises at least one of an oxide film and an oxynitride film; A nanometer polycrystalline diamond film layer is formed on the intermediate bonding layer by a microwave chemical deposition method.

6. The method for manufacturing a cutting tool according to claim 5, characterized in that: The method further comprises the steps of: forming a cubic boron nitride film layer on the nano-polycrystalline diamond film layer by a high-power pulsed magnetron sputtering method; and or, the intermediate bonding layer comprises at least one of AlCrON, AlCrO and AlCrSiON.

7. The method for manufacturing a cutting tool according to claim 5, characterized in that: The method also includes the step of: using a plasma method to clean the cutting tool substrate.

8. A cutting tool manufacturing device, characterized in that: It includes a vacuum furnace, a heating device, a vacuum device, a high-power pulse sputtering device, an arc evaporation device, a microwave generating device, a pulse bias device, a gas flow control device and a temperature control device; The heating device, the vacuum device, the high-power pulse sputtering device, the arc evaporation device, the microwave generating device, the pulse bias device, the gas flow control device and the temperature control device are at least partially arranged in the inner cavity of the vacuum furnace; The heating device is used to heat the inner cavity; The vacuum device is used to evacuate the inner cavity and detect the vacuum degree; The target material of the high-power pulse sputtering device, the target material of the arc evaporation device and the output end of the microwave generating device are arranged in the inner cavity; The pulse bias device is electrically connected to the high-power pulse sputtering device, the arc evaporation device and the microwave generating device respectively; The gas flow control device is used to input gas into the inner cavity; The temperature control device is electrically connected to the heating device and is used to control the temperature of the inner cavity.

9. The manufacturing equipment of the cutting tool according to claim 8, characterized in that: The arc evaporation device is provided with one or two arc targets for depositing a preliminary bonding layer and an intermediate bonding layer; wherein the preliminary bonding layer comprises one of CrN and TiN, and the intermediate bonding layer comprises at least one of an oxide film and a nitride oxide film; The microwave generating device is provided with at least one microwave deriver for depositing a nano-polycrystalline diamond film; The high-power pulse sputtering device is provided with one or two high-power pulse sputtering targets for depositing cubic boron nitride films.

10. The manufacturing equipment of the cutting tool according to claim 8, characterized in that: The inner wall of the vacuum furnace is provided with a cold water pipeline; or, The arc evaporation device is provided with an arc pure chromium pure titanium target and an arc aluminum silicon target; or, The high-power pulse sputtering device is provided with a sputtering pure boron target; or, The temperature control device is provided with a furnace temperature control system and a cold water control system.

Images