Biomedical diamond composite material and preparation method thereof

Abstract

The invention provides a biomedical diamond composite material and a preparation method thereof. The preparation method comprises the following steps: preparing a matrix with a special-shaped structure; covering the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate; and depositing a diamond film layer on the surface of the intermediate based on a chemical vapor deposition method to obtain the biomedical diamond composite material, wherein when the diamond film layer is deposited, based on the surface shape of the intermediate, the air outlet direction of an air outlet in the deposition equipment is controlled to move along the surface of the intermediate auxiliary layer until the diamond film layer completely covers the intermediate auxiliary layer. According to the invention, the middle auxiliary layer coated on the surface of the base body with the special-shaped structure is used as a buffer layer, so that the bonding strength between layers is enhanced; by controlling the air outlet direction in the deposition process, control over the thickness of the film layer is achieved, the thickness of the diamond film layer is uniform, and the diamond film layer can be applied to the human body environment and cannot bring negative effects.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical materials, and in particular to a biomedical diamond composite material and a preparation method thereof. Background Art

[0002] With the continuous advancement of medical technology, the requirements for medical surgical tools, human implants and other medical materials (especially human implants) are getting higher and higher. Ideal human implant materials not only need to have good biocompatibility, biological activity, no adverse effects on surrounding bone tissue, no rejection and no toxic side effects, but also need to have sufficient hardness, appropriate strength, excellent physical and chemical properties, sufficient load capacity, stable surface properties, good fatigue resistance, good wear resistance and corrosion resistance, etc.

[0003] At present, the most commonly used human implant materials are titanium alloy and silicon nitride. Titanium alloy will release trace ions after implantation into the human body, which will lead to contamination of tissue cells and cause adverse reactions such as inflammation inside the human body. Because diamond has excellent properties such as low friction coefficient, high hardness, excellent chemical stability and good biocompatibility, the applicant tried to use titanium alloy as the matrix and cover the surface with diamond film to solve the problem of titanium alloy releasing trace ions after implantation into the human body in the early stage of research. However, human implants are usually various bone implant materials such as human skeleton, artificial joints, dental materials, etc., which are generally of special-shaped structures. It is difficult to cover with diamond film, and it is difficult to obtain a diamond film with uniform film thickness. In the special biological environment of the human body, the diamond film layer with uneven thickness is exposed to the human body environment. Once the thin layer is damaged, the surface properties will be unstable, which will have an adverse effect on the human body. In addition, the applicant also found during the research process that whether the diamond film is loaded on the surface of the titanium alloy material or the diamond film is loaded on the surface of the silicon nitride material, the bonding strength is not ideal, and the diamond film will be detached after long-term use, which will cause the human implant to fail on the one hand, and on the other hand, the detached diamond film is in a free state in the human body environment, which has an adverse effect on the human body. Therefore, the field urgently needs a biomedical diamond composite material with uniform film thickness and high bonding strength with the substrate. Summary of the invention

[0004] The present invention provides a biomedical diamond composite material and a preparation method thereof to solve the above problems.

[0005] On the one hand, the present invention provides a method for preparing a biomedical diamond composite material, comprising the following steps: preparing a special-shaped structural substrate; covering the surface of the special-shaped structural substrate with an intermediate auxiliary layer to obtain an intermediate; depositing a diamond film layer on the surface of the intermediate based on a chemical vapor deposition method to obtain the biomedical diamond composite material; wherein, when depositing the diamond film layer, based on the surface shape of the intermediate, the outlet direction of the gas outlet in the deposition equipment is controlled to move along the surface of the intermediate auxiliary layer until the diamond film layer completely covers the intermediate auxiliary layer.

[0006] In some embodiments of the present invention, the special-shaped structural matrix is ​​selected from zirconium oxide, silicon nitride or titanium alloy, and / or the special-shaped structural matrix is ​​a special-shaped structural matrix with the same shape as the bone structure at the location to be implanted.

[0007] In some embodiments of the present invention, when depositing a diamond film layer, the air outlets of each air inlet pipe of the deposition equipment are adjusted to face the intermediate auxiliary layer; the digital three-dimensional model of the intermediate is imported into the control system, and during the deposition of the diamond film layer, the deposition status of the diamond film layer is captured in real time by an image acquisition device electrically connected to the control system; according to the real-time deposition status of the diamond film layer, the outlet direction of the air inlet pipe is controlled by a changing device to turn to a position where the diamond film layer is thinner, until a diamond film layer of uniform thickness is formed on the surface of the intermediate auxiliary layer.

[0008] In some embodiments of the present invention, the direction changing device includes a stepper motor connected to the air inlet pipe and / or when depositing the diamond film layer, the deposition workbench of the deposition equipment is rotated to cooperate with the turning direction of the air outlet of the air inlet pipe, thereby completing the deposition of the diamond film layer.

[0009] In some embodiments of the present invention, when depositing a diamond film, the power is 100-110 kw, the gas pressure is 60-65 Torr, the temperature is 900-1100° C., the hydrogen flow rate is 5000-6000 ml / min, and the methane flow rate is 120-150 ml / min.

[0010] In some embodiments of the present invention, the intermediate auxiliary layer is one of a Si buffer layer, a TiN buffer layer, and an AlN buffer layer; and the intermediate auxiliary layer is coated on the surface of the special-shaped structural substrate by radio frequency magnetron sputtering.

[0011] In some embodiments of the present invention, the RF magnetron sputtering method includes a first sputtering stage and a second sputtering stage performed sequentially; wherein the sputtering gas pressure of the first sputtering stage is 0.3-0.5Pa, the sputtering power is 165-170W, and the sputtering time is 0.5-1h; the sputtering gas pressure of the second sputtering stage is 0.3-0.5Pa, the sputtering power is 110-115W, and the sputtering time is 1-1.5h.

[0012] In some embodiments of the present invention, before the surface of the special-shaped structural substrate is covered with the intermediate auxiliary layer, the special-shaped structural substrate is pretreated; the pretreatment process is as follows: the special-shaped structural substrate is cleaned with an acid solution or an alkaline solution, then placed in clean water for ultrasonic vibration for 10-20 minutes, and then cleaned with alcohol and wiped dry for use.

[0013] In some embodiments of the present invention, after the diamond film layer is deposited, its surface is polished and ground using diamond powder, and then disinfected and sterilized to obtain the biomedical diamond composite material.

[0014] On the other hand, the present invention further provides a biomedical diamond composite material, which is prepared according to any of the above-mentioned methods for preparing the biomedical diamond composite material.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) The present invention uses the intermediate auxiliary layer covered on the surface of the special-shaped structure substrate as a buffer layer to enhance the bonding strength between the layers, reduce the probability of diamond film detachment, and avoid the problem of film detachment causing human implant failure and the detached diamond film being in a free state in the human environment, which has an adverse effect on the human body. In addition, the present invention controls the gas distribution in the deposition equipment by controlling the gas outlet direction during the deposition process to achieve control of the thickness of the deposited film layer. The diamond film layer has a uniform thickness and can be applied to the human environment without causing any negative impact. It avoids the problem of uneven thickness diamond film layer being damaged when exposed to the human environment, resulting in unstable surface properties and thus having an adverse effect on the human body. The biomedical diamond composite material prepared by the preparation method of the present invention has good biocompatibility, high hardness, good corrosion resistance, low friction coefficient, no rejection and toxic side effects on bone tissue and carbon-based organisms, and a wide range of applications, and can be used in human skeleton, dental field, medical surgical knives, etc.

[0017] (2) When depositing a diamond film layer, the present invention collects the deposition status of the diamond film layer in real time and uses the real-time deposition status of the diamond film layer as a basis to accurately adjust the gas outlet direction to a position where the diamond film layer is thinner. At the same time, the deposition parameters such as power, gas pressure, temperature, hydrogen flow rate and methane flow rate are designed to achieve precise control of the thickness of the diamond film layer, thereby obtaining a diamond film layer with uniform thickness.

[0018] (3) The present invention adopts a staged RF magnetron sputtering method to coat the intermediate auxiliary layer. The first sputtering stage is the nucleation stage. High-power sputtering is used. Under a higher bias voltage, the nucleation rate and density of the film can be improved, and the problem of low bias voltage affecting the nucleation rate of the film can be avoided. The setting of the sputtering time ensures the nucleation rate and density on the one hand, and avoids the problem of etching caused by high bias voltage for too long, which leads to more defects in the film on the other hand. The second sputtering stage is the growth stage. Low-power sputtering is used. Under a lower bias voltage, the growth stage of the buffer layer film tends to be stable. As a result, the intermediate auxiliary layer obtained presents a better surface state. When a diamond film is deposited on its surface, the generation of impurity phases such as amorphous carbon including graphite phase during the deposition of the diamond film can be suppressed, thereby improving the bonding strength between the intermediate auxiliary layer and the diamond film. DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions and advantages of the present invention more clear, various aspects of the present invention will be described in detail below in conjunction with specific embodiments. However, these specific embodiments are only used to illustrate the present invention and do not constitute any limitation on the scope of protection and essential content of the present invention.

[0020] Embodiment 1:

[0021] This embodiment provides a method for preparing a biomedical diamond composite material, comprising the following steps:

[0022] S1. Prepare a special-shaped structural matrix: the special-shaped structural matrix is ​​selected from zirconium oxide, silicon nitride or titanium alloy; and / or the special-shaped structural matrix is ​​a special-shaped structural matrix with the same shape as the bone structure to be implanted, for example, when the bone structure to be implanted is a hip joint, the shape of the special-shaped structural matrix is ​​the same as the shape of the hip joint. In this embodiment, the preparation method of the special-shaped structural matrix is ​​not limited, for example, it can be prepared by mechanical processing or 3D printing.

[0023] S2. Covering the surface of the special-shaped structural substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is one of a Si buffer layer, a TiN buffer layer, and an AlN buffer layer; covering the surface of the special-shaped structural substrate with the intermediate auxiliary layer by radio frequency magnetron sputtering. In this embodiment, the radio frequency magnetron sputtering method includes a first sputtering stage and a second sputtering stage performed in sequence; wherein the sputtering gas pressure of the first sputtering stage is 0.3-0.5Pa, the sputtering power is 165-170W, and the sputtering time is 0.5-1h; the sputtering gas pressure of the second sputtering stage is 0.3-0.5Pa, the sputtering power is 110-115W, and the sputtering time is 1-1.5h.

[0024] S3. Depositing a diamond film layer on the surface of the intermediate based on chemical vapor deposition to obtain a biomedical diamond composite material; wherein, when depositing the diamond film layer, based on the surface shape of the intermediate, controlling the outlet direction of the gas outlet in the deposition equipment to move along the surface of the intermediate auxiliary layer until the diamond film layer completely covers the intermediate auxiliary layer. Specifically: based on the material selection of the special-shaped structural base, a suitable substrate (generally molybdenum, graphite and other materials) is selected, and the substrate (different substrates have different thermal conductivity coefficients. If molybdenum material is used, a layer of copper mesh is generally placed under the substrate, and if graphite material is used, copper mesh may not be used for heat conduction) is installed on the deposition workbench, and the intermediate is placed on the substrate in the HFCVD deposition furnace to ensure that the deposition surface (i.e., the surface of the intermediate auxiliary layer) is exposed to the furnace chamber. After the hot wire rack is installed, deposition is carried out under the conditions of a power of 100-110kw, a gas pressure of 60-65Torr, a temperature of 900-1100°C, a hydrogen flow rate of 5000-6000ml / min, and a methane flow rate of 120-150ml / min. According to the thickness of the diamond film layer to be deposited, a suitable deposition time (deposition rate of 5-7μm / h) is set. In this embodiment, when depositing the diamond film layer, the air outlets of each air inlet pipe of the deposition equipment are adjusted to face the intermediate auxiliary layer; the digital three-dimensional model of the intermediate is imported into the control system, and during the deposition of the diamond film layer, the deposition state of the diamond film layer is collected in real time by an image acquisition device electrically connected to the control system; according to the real-time deposition state of the diamond film layer, the outlet direction of the air outlet of the air inlet pipe is controlled by a turning device to turn to a position where the thickness of the diamond film layer is thinner, until a diamond film layer with uniform thickness is formed on the surface of the intermediate auxiliary layer. In this embodiment, the control system, the image acquisition device, and the turning device are not limited in structure. For example, the image acquisition device can be a high-resolution manual focus camera, which is convenient for real-time observation of the film growth in the furnace, and then position adjustment is performed. The turning device can be a stepping motor connected to the air inlet pipe. In this embodiment, preferably, when depositing the diamond film layer, the deposition workbench of the deposition equipment is rotated to match the turning of the outlet direction of the air outlet of the air inlet pipe, thereby completing the deposition of the diamond film layer. In this embodiment, preferably, the rotation speed of the deposition workbench is 0.3-0.4 r / min, so that the diamond can be evenly deposited on the surface of the material.

[0025] In this embodiment, preferably, before the surface of the special-shaped structural substrate of S2 is covered with the intermediate auxiliary layer, the special-shaped structural substrate is pretreated. The pretreatment process is as follows: the special-shaped structural substrate is cleaned with an acid solution (generally a dilute hydrofluoric acid solution with a mass concentration of 0.1%-1%) or an alkali solution (generally a natural alkali with a concentration of 1%-2%), then placed in clean water for ultrasonic vibration for 10-20 minutes, and then cleaned with alcohol and wiped dry for use.

[0026] In this embodiment, preferably, after the diamond film layer is deposited, the surface is polished and ground with diamond powder (for example, 0-0.5 μm to 6-10 μm diamond powder can be used for polishing, and 10-15 μm to 22-36 μm diamond powder can be used for grinding) to make the surface smooth and flat to meet the requirements of use, and then disinfected and sterilized (first use medical alcohol for preliminary cleaning, then use a neutral multi-enzyme cleaning agent for cleaning, and then use an ultrasonic cleaning machine for cleaning, boil and disinfect, do not use lubricants to lubricate to avoid residues, dry in a drying cabinet and then package, and then use a high-temperature and high-pressure sterilizer or an epoxy-acetylene sterilizer for sterilization, so as to meet the conditions for use), to obtain a biomedical diamond composite material.

[0027] This embodiment also provides a biomedical diamond composite material, which is prepared according to the preparation method of the biomedical diamond composite material of this embodiment.

[0028] Embodiment 2:

[0029] This embodiment provides a method for preparing a biomedical diamond composite material, comprising the following steps:

[0030] S1. Preparation of a special-shaped structural matrix: The special-shaped structural matrix is ​​selected from titanium alloy; and / or the special-shaped structural matrix is ​​a special-shaped structural matrix with the same shape as the bone structure to be implanted, for example, when the bone structure to be implanted is an acetabular cup, the shape of the special-shaped structural matrix is ​​the same as the shape of the acetabular cup. In this embodiment, the preparation method of the special-shaped structural matrix is ​​not limited, for example, it can be prepared by mechanical processing or 3D printing.

[0031] S2. Pretreatment of the special-shaped structural matrix: clean the special-shaped structural matrix with an acid solution (generally a dilute hydrofluoric acid solution with a mass concentration of 0.1%) or an alkali solution (generally a natural alkali with a concentration of 1%), then put it in clean water for ultrasonic vibration for 10 minutes, and then clean it with alcohol and wipe it dry for later use.

[0032] S3, coating the surface of the special-shaped structural substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is a Si buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structural substrate by radio frequency magnetron sputtering. In this embodiment, the radio frequency magnetron sputtering method includes a first sputtering stage and a second sputtering stage performed in sequence; wherein the sputtering gas pressure of the first sputtering stage is 0.3Pa, the sputtering power is 165W, and the sputtering time is 1h; the sputtering gas pressure of the second sputtering stage is 0.3Pa, the sputtering power is 110W, and the sputtering time is 1.5h.

[0033] S4. Deposit a diamond film layer on the surface of the intermediate body based on chemical vapor deposition; wherein, when depositing the diamond film layer, based on the surface shape of the intermediate body, control the outlet direction of the gas outlet in the deposition equipment to move along the surface of the intermediate auxiliary layer until the diamond film layer completely covers the intermediate auxiliary layer. Specifically: place a layer of copper mesh under the molybdenum substrate and install it on the deposition workbench, place the intermediate body on the molybdenum substrate in the HFCVD deposition furnace, ensure that the deposition surface (i.e., the surface of the intermediate auxiliary layer) is exposed to the furnace chamber, and after installing the hot wire rack, perform deposition under the conditions of 100kw power, 60Torr pressure, 900℃ temperature, 6000ml / min hydrogen flow rate, and 150ml / min methane flow rate. Set the appropriate deposition time (deposition speed 5μm / h) according to the thickness of the diamond film layer to be deposited. In this embodiment, when depositing the diamond film layer, the air outlets of each air inlet pipe of the deposition equipment are adjusted to face the intermediate auxiliary layer; the digital three-dimensional model of the intermediate is imported into the control system, and during the deposition of the diamond film layer, the deposition state of the diamond film layer is collected in real time by an image acquisition device electrically connected to the control system; according to the real-time deposition state of the diamond film layer, the outlet direction of the air outlet of the air inlet pipe is controlled by a turning device to turn to a position where the thickness of the diamond film layer is thinner, until a diamond film layer with uniform thickness is formed on the surface of the intermediate auxiliary layer. In this embodiment, the control system, the image acquisition device, and the turning device are not limited in structure. For example, the image acquisition device can be a high-resolution manual focus camera, which is convenient for real-time observation of the film growth in the furnace, and then position adjustment is performed. The turning device can be a stepping motor connected to the air inlet pipe. In this embodiment, preferably, when depositing the diamond film layer, the deposition workbench of the deposition equipment is rotated to match the turning of the outlet direction of the air outlet of the air inlet pipe, thereby completing the deposition of the diamond film layer. In this embodiment, preferably, the rotation speed of the deposition workbench is 0.3 r / min, so that the diamond can be evenly deposited on the surface of the material.

[0034] S5. Post-treatment: Use diamond powder to polish and grind the surface of S4 product (for example, 0-0.5μm to 6-10μm diamond powder can be used for polishing, and 10-15μm to 22-36μm diamond powder can be used for grinding) to make the surface smooth and flat to meet the requirements of use, and then disinfect and sterilize (first use medical alcohol for preliminary cleaning, then use neutral multi-enzyme cleaning agent for cleaning, and then use ultrasonic cleaning machine for cleaning, boil and disinfect, do not use lubricants for lubrication to avoid residues, dry in a drying cabinet and then package, and then use a high temperature and high pressure sterilizer or epoxy acetylene sterilizer for sterilization to meet the conditions for use) to obtain a biomedical diamond composite material.

[0035] This embodiment also provides a biomedical diamond composite material, which is prepared according to the preparation method of the biomedical diamond composite material of this embodiment.

[0036] Embodiment 3:

[0037] This embodiment provides a method for preparing a biomedical diamond composite material, comprising the following steps:

[0038] S1. Prepare a special-shaped structural matrix: the special-shaped structural matrix is ​​selected from silicon nitride; and / or the special-shaped structural matrix is ​​a special-shaped structural matrix with the same shape as the bone structure to be implanted, for example, when the bone structure to be implanted is a hip joint, the shape of the special-shaped structural matrix is ​​the same as the shape of the hip joint. In this embodiment, the preparation method of the special-shaped structural matrix is ​​not limited, for example, it can be prepared by mechanical processing or 3D printing.

[0039] S2. Pretreatment of the special-shaped structural substrate: clean the special-shaped structural substrate with an acid solution (generally a dilute hydrofluoric acid solution with a mass concentration of 0.6%) or an alkali solution (generally a natural alkali with a concentration of 1.5%), then put it in clean water for ultrasonic vibration for 15 minutes, and then clean it with alcohol and wipe it dry for later use.

[0040] S3, coating the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is a TiN buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structure substrate by radio frequency magnetron sputtering. In this embodiment, the radio frequency magnetron sputtering method includes a first sputtering stage and a second sputtering stage performed in sequence; wherein the sputtering gas pressure of the first sputtering stage is 0.4Pa, the sputtering power is 167W, and the sputtering time is 0.7h; the sputtering gas pressure of the second sputtering stage is 0.4Pa, the sputtering power is 112W, and the sputtering time is 1.2h.

[0041] S4. Deposit a diamond film layer on the surface of the intermediate body based on chemical vapor deposition; wherein, when depositing the diamond film layer, based on the surface shape of the intermediate body, control the outlet direction of the gas outlet in the deposition equipment to move along the surface of the intermediate auxiliary layer until the diamond film layer completely covers the intermediate auxiliary layer. Specifically: place a layer of copper mesh under the molybdenum substrate and install it on the deposition workbench, place the intermediate body on the molybdenum substrate in the HFCVD deposition furnace, ensure that the deposition surface (i.e., the surface of the intermediate auxiliary layer) is exposed to the furnace chamber, and after installing the hot wire rack, perform deposition under the conditions of 105kw power, 62Torr pressure, 1000℃ temperature, 5500ml / min hydrogen flow rate, and 130ml / min methane flow rate. Set the appropriate deposition time (deposition speed 6μm / h) according to the thickness of the diamond film layer to be deposited. In this embodiment, when depositing the diamond film layer, the air outlets of each air inlet pipe of the deposition equipment are adjusted to face the intermediate auxiliary layer; the digital three-dimensional model of the intermediate is imported into the control system, and during the deposition of the diamond film layer, the deposition state of the diamond film layer is collected in real time by an image acquisition device electrically connected to the control system; according to the real-time deposition state of the diamond film layer, the outlet direction of the air outlet of the air inlet pipe is controlled by a turning device to turn to a position where the thickness of the diamond film layer is thinner, until a diamond film layer with uniform thickness is formed on the surface of the intermediate auxiliary layer. In this embodiment, the control system, the image acquisition device, and the turning device are not limited in structure. For example, the image acquisition device can be a high-resolution manual focus camera, which is convenient for real-time observation of the film growth in the furnace, and then position adjustment is performed. The turning device can be a stepping motor connected to the air inlet pipe. In this embodiment, preferably, when depositing the diamond film layer, the deposition workbench of the deposition equipment is rotated to match the turning of the outlet direction of the air outlet of the air inlet pipe, thereby completing the deposition of the diamond film layer. In this embodiment, preferably, the rotation speed of the deposition workbench is 0.35 r / min, so that the diamond can be evenly deposited on the surface of the material.

[0042] S5. Post-treatment: Use diamond powder to polish and grind the surface of S4 product (for example, 0-0.5μm to 6-10μm diamond powder can be used for polishing, and 10-15μm to 22-36μm diamond powder can be used for grinding) to make the surface smooth and flat to meet the requirements of use, and then disinfect and sterilize (first use medical alcohol for preliminary cleaning, then use neutral multi-enzyme cleaning agent for cleaning, and then use ultrasonic cleaning machine for cleaning, boil and disinfect, do not use lubricants for lubrication to avoid residues, dry in a drying cabinet and then package, and then use a high temperature and high pressure sterilizer or epoxy acetylene sterilizer for sterilization to meet the conditions for use) to obtain a biomedical diamond composite material.

[0043] This embodiment also provides a biomedical diamond composite material, which is prepared according to the preparation method of the biomedical diamond composite material of this embodiment.

[0044] Embodiment 4:

[0045] This embodiment provides a method for preparing a biomedical diamond composite material, comprising the following steps:

[0046] S1. Prepare a special-shaped structural matrix: the special-shaped structural matrix is ​​selected from zirconium oxide; and / or the special-shaped structural matrix is ​​a special-shaped structural matrix with the same shape as the bone structure to be implanted, for example, when the bone structure to be implanted is an acetabular cup, the shape of the special-shaped structural matrix is ​​the same as the shape of the acetabular cup. In this embodiment, the preparation method of the special-shaped structural matrix is ​​not limited, for example, it can be prepared by mechanical processing or 3D printing.

[0047] S2. Pretreatment of the special-shaped structural substrate: clean the special-shaped structural substrate with an acid solution (generally a dilute hydrofluoric acid solution with a mass concentration of 1%) or an alkali solution (generally a natural alkali with a concentration of 2%), then put it in clean water for ultrasonic vibration for 20 minutes, and then clean it with alcohol and wipe it dry for later use.

[0048] S3, coating the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is an AlN buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structure substrate by radio frequency magnetron sputtering. In this embodiment, the radio frequency magnetron sputtering method includes a first sputtering stage and a second sputtering stage performed in sequence; wherein the sputtering gas pressure of the first sputtering stage is 0.5Pa, the sputtering power is 170W, and the sputtering time is 0.5h; the sputtering gas pressure of the second sputtering stage is 0.5Pa, the sputtering power is 115W, and the sputtering time is 1h.

[0049] S4. Deposit a diamond film layer on the surface of the intermediate body based on chemical vapor deposition; wherein, when depositing the diamond film layer, based on the surface shape of the intermediate body, control the outlet direction of the gas outlet in the deposition equipment to move along the surface of the intermediate auxiliary layer until the diamond film layer completely covers the intermediate auxiliary layer. Specifically: install the graphite substrate on the deposition workbench, place the intermediate body on the graphite substrate in the HFCVD deposition furnace, ensure that the deposition surface (i.e., the surface of the intermediate auxiliary layer) is exposed to the furnace chamber, and after installing the hot wire rack, perform deposition under the conditions of 110kw power, 65Torr pressure, 1100℃ temperature, 5000ml / min hydrogen flow rate, and 120ml / min methane flow rate. Set the appropriate deposition time (deposition rate 7μm / h) according to the thickness of the diamond film layer to be deposited. In this embodiment, when depositing the diamond film layer, the air outlets of each air inlet pipe of the deposition equipment are adjusted to face the intermediate auxiliary layer; the digital three-dimensional model of the intermediate is imported into the control system, and during the deposition of the diamond film layer, the deposition state of the diamond film layer is collected in real time by an image acquisition device electrically connected to the control system; according to the real-time deposition state of the diamond film layer, the outlet direction of the air outlet of the air inlet pipe is controlled by a turning device to turn to a position where the thickness of the diamond film layer is thinner, until a diamond film layer with uniform thickness is formed on the surface of the intermediate auxiliary layer. In this embodiment, the control system, the image acquisition device, and the turning device are not limited in structure. For example, the image acquisition device can be a high-resolution manual focus camera, which is convenient for real-time observation of the film growth in the furnace, and then position adjustment is performed. The turning device can be a stepping motor connected to the air inlet pipe. In this embodiment, preferably, when depositing the diamond film layer, the deposition workbench of the deposition equipment is rotated to match the turning of the outlet direction of the air outlet of the air inlet pipe, thereby completing the deposition of the diamond film layer. In this embodiment, preferably, the rotation speed of the deposition workbench is 0.4 r / min, so that the diamond can be evenly deposited on the surface of the material.

[0050] S5. Post-treatment: Use diamond powder to polish and grind the surface of S4 product (for example, 0-0.5μm to 6-10μm diamond powder can be used for polishing, and 10-15μm to 22-36μm diamond powder can be used for grinding) to make the surface smooth and flat to meet the requirements of use, and then disinfect and sterilize (first use medical alcohol for preliminary cleaning, then use neutral multi-enzyme cleaning agent for cleaning, and then use ultrasonic cleaning machine for cleaning, boil and disinfect, do not use lubricants for lubrication to avoid residues, dry in a drying cabinet and then package, and then use a high temperature and high pressure sterilizer or epoxy acetylene sterilizer for sterilization to meet the conditions for use) to obtain a biomedical diamond composite material.

[0051] This embodiment also provides a biomedical diamond composite material, which is prepared according to the preparation method of the biomedical diamond composite material of this embodiment.

[0052] Comparative Example 1:

[0053] Comparative Example 1 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 1 and Example 2 is only that:

[0054] S3, coating the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is a Si buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structure substrate by radio frequency magnetron sputtering. The radio frequency magnetron sputtering method is not carried out in stages, and the sputtering parameters are: sputtering pressure is 0.3Pa, sputtering power is 165W, and sputtering time is 2.5h.

[0055] Comparative Example 2:

[0056] Comparative Example 2 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 2 and Example 2 is only that:

[0057] S3, coating the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is a Si buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structure substrate by radio frequency magnetron sputtering. The radio frequency magnetron sputtering method is not carried out in stages, and the sputtering parameters are: sputtering pressure is 0.3Pa, sputtering power is 110W, and sputtering time is 2.5h.

[0058] Comparative Example 3:

[0059] Comparative Example 3 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 3 and Example 2 is only that:

[0060] S4. Deposit a diamond film layer on the surface of the intermediate based on chemical vapor deposition. Specifically: place a layer of copper mesh under the molybdenum substrate and install it on the deposition workbench, place the intermediate on the molybdenum substrate in the HFCVD deposition furnace, ensure that the deposition surface (i.e., the surface of the intermediate auxiliary layer) is exposed to the furnace chamber, and after installing the hot wire rack, perform deposition under the conditions of 100kw power, 60Torr pressure, 900℃ temperature, 6000ml / min hydrogen flow rate, and 150ml / min methane flow rate. Set the appropriate deposition time (deposition rate 5μm / h) according to the thickness of the diamond film layer to be deposited.

[0061] Comparative Example 4:

[0062] Comparative Example 4 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 4 and Example 3 is only that:

[0063] S3, coating the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is a TiN buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structure substrate by radio frequency magnetron sputtering. The radio frequency magnetron sputtering method is not carried out in stages, and the sputtering parameters are: sputtering pressure is 0.4Pa, sputtering power is 167W, and sputtering time is 1.9h.

[0064] Comparative Example 5:

[0065] Comparative Example 5 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 5 and Example 3 is only that:

[0066] S3, coating the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is a TiN buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structure substrate by radio frequency magnetron sputtering. The radio frequency magnetron sputtering method is not carried out in stages, and the sputtering parameters are: sputtering pressure is 0.4Pa, sputtering power is 112W, and sputtering time is 1.9h.

[0067] Comparative Example 6:

[0068] Comparative Example 6 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 6 and Example 3 is only that:

[0069] S4. Deposit a diamond film layer on the surface of the intermediate based on chemical vapor deposition. Specifically: place a layer of copper mesh under the molybdenum substrate and install it on the deposition workbench, place the intermediate on the molybdenum substrate in the HFCVD deposition furnace, ensure that the deposition surface (i.e., the surface of the intermediate auxiliary layer) is exposed to the furnace chamber, and after installing the hot wire rack, perform deposition under the conditions of 105kw power, 62Torr pressure, 1000℃ temperature, 5500ml / min hydrogen flow rate, and 130ml / min methane flow rate. Set the appropriate deposition time (deposition rate 6μm / h) according to the thickness of the diamond film layer to be deposited.

[0070] Comparative Example 7:

[0071] Comparative Example 7 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 7 and Example 4 is only that:

[0072] S3, coating the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is an AlN buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structure substrate by radio frequency magnetron sputtering. The radio frequency magnetron sputtering method is not carried out in stages, and the sputtering parameters are: sputtering pressure is 0.5Pa, sputtering power is 170W, and sputtering time is 1.5h.

[0073] Comparative Example 8:

[0074] Comparative Example 8 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 8 and Example 4 is only that:

[0075] S3, coating the surface of the special-shaped structure substrate with an intermediate auxiliary layer to obtain an intermediate: the intermediate auxiliary layer is an AlN buffer layer; the intermediate auxiliary layer is coated on the surface of the special-shaped structure substrate by radio frequency magnetron sputtering. The radio frequency magnetron sputtering method is not carried out in stages, and the sputtering parameters are: sputtering pressure is 0.5Pa, sputtering power is 115W, and sputtering time is 1.5h.

[0076] Comparative Example 9:

[0077] Comparative Example 9 discloses a biomedical diamond composite material and a preparation method thereof. The difference between Comparative Example 9 and Example 4 is only that:

[0078] S4. Deposit a diamond film layer on the surface of the intermediate based on chemical vapor deposition. Specifically: install the graphite substrate on the deposition workbench, place the intermediate on the graphite substrate in the HFCVD deposition furnace, ensure that the deposition surface (i.e., the surface of the intermediate auxiliary layer) is exposed to the furnace chamber, install the hot wire rack, and perform deposition under the conditions of 110kw power, 65Torr pressure, 1100℃ temperature, 5000ml / min hydrogen flow rate, and 120ml / min methane flow rate. Set the appropriate deposition time (deposition rate 7μm / h) according to the thickness of the diamond film layer to be deposited.

[0079] Biomedical diamond composite materials were prepared from Examples 2-4 and Comparative Examples 1-9.

[0080] Compared with Comparative Examples 1-3, Example 2 shows that the diamond film layer of the biomedical diamond composite material of Example 2 has a uniform thickness, and the bonding strength between the layers is high under a simulated human body environment, and it is not easy to crack or detach after long-term use; the diamond film layer of the biomedical diamond composite material of Comparative Examples 1-2 has a relatively uniform thickness, but the bonding strength between the layers is low under a simulated human body environment, especially between the intermediate auxiliary layer and the diamond film layer, and the film layer detachment problem occurs under the same use time as Example 2; the diamond film layer of the biomedical diamond composite material of Comparative Example 3 has an uneven thickness, and the bonding strength between the layers is high under a simulated human body environment, and it is not easy to crack or detach after the same use time as Example 2.

[0081] Compared with Comparative Examples 4-6, Example 3 shows that the diamond film layer of the biomedical diamond composite material of Example 3 has uniform thickness, high interlayer bonding strength under a simulated human body environment, and is not easy to crack or detach after long-term use; the diamond film layer of the biomedical diamond composite material of Comparative Examples 4-5 has relatively uniform thickness, but low interlayer bonding strength under a simulated human body environment, especially the intermediate auxiliary layer and the diamond film layer, and the film layer detachment problem occurs under the same use time as Example 3; the diamond film layer of the biomedical diamond composite material of Comparative Example 6 has uneven thickness, high interlayer bonding strength under a simulated human body environment, and is not easy to crack or detach after the same use time as Example 3.

[0082] Compared with Comparative Examples 7-9, Example 4 has a uniform thickness of the diamond film layer of the biomedical diamond composite material of Example 4, and has a high bonding strength between the layers under a simulated human body environment, and is not easy to crack or detach after long-term use; the diamond film layer of the biomedical diamond composite material of Comparative Examples 7-8 has a relatively uniform thickness, but has a low bonding strength between the layers under a simulated human body environment, especially between the intermediate auxiliary layer and the diamond film layer, and the film layer detaches after the same use time as Example 4; the diamond film layer of the biomedical diamond composite material of Comparative Example 9 has an uneven thickness, has a high bonding strength between the layers under a simulated human body environment, is not easy to crack or detach after the same use time as Example 4.

[0083] The present invention has been described above in conjunction with specific embodiments. These specific embodiments are merely exemplary and cannot be used to limit the scope of protection of the present invention. Those skilled in the art may make various modifications, changes or substitutions without departing from the essence of the present invention. Therefore, various equivalent changes made according to the present invention still fall within the scope covered by the present invention.

Claims

1. A method for preparing a biomedical diamond composite material, characterized in that: The following steps are involved: preparing a special-shaped structural matrix; Covering the surface of the special-shaped structural substrate with an intermediate auxiliary layer to obtain an intermediate; Depositing a diamond film layer on the surface of the intermediate based on chemical vapor deposition to obtain the biomedical diamond composite material; When the diamond film is deposited, based on the surface shape of the intermediate, the outlet direction of the gas outlet in the deposition device is controlled to move along the surface of the intermediate auxiliary layer until the diamond film completely covers the intermediate auxiliary layer.

2. The method for preparing the biomedical diamond composite material according to claim 1, characterized in that: The special-shaped structural matrix is ​​made of zirconium oxide, silicon nitride or titanium alloy, and / or the special-shaped structural matrix is ​​a special-shaped structural matrix with the same shape as the bone structure at the position to be implanted.

3. The method for preparing the biomedical diamond composite material according to claim 1, characterized in that: When depositing the diamond film layer, the gas outlets of each gas inlet pipe of the deposition equipment are adjusted to face the intermediate auxiliary layer; The digital three-dimensional model of the intermediate is imported into the control system, and during the deposition process of the diamond film layer, the deposition state of the diamond film layer is collected in real time through an image acquisition device electrically connected to the control system; According to the real-time deposition state of the diamond film layer, the outlet direction of the air inlet pipe outlet is controlled by the direction-changing device to turn to the position where the diamond film layer is thinner, until a diamond film layer of uniform thickness is formed on the surface of the intermediate auxiliary layer.

4. The method for preparing the biomedical diamond composite material according to claim 3, characterized in that: The direction-changing device includes a stepper motor connected to the air inlet pipe and / or when depositing the diamond film layer, the deposition workbench of the deposition equipment rotates to match the direction of the air outlet of the air inlet pipe, thereby completing the deposition of the diamond film layer.

5. The method for preparing the biomedical diamond composite material according to claim 1, characterized in that: When depositing the diamond film layer, the power is 100-110kw, the gas pressure is 60-65Torr, the temperature is 900-1100°C, the hydrogen flow rate is 5000-6000ml / min, and the methane flow rate is 120-150ml / min.

6. The method for preparing the biomedical diamond composite material according to claim 1, characterized in that: The intermediate auxiliary layer is one of a Si buffer layer, a TiN buffer layer, and an AlN buffer layer; The intermediate auxiliary layer is coated on the surface of the special-shaped structural substrate by radio frequency magnetron sputtering.

7. The method for preparing the biomedical diamond composite material according to claim 6, characterized in that: The radio frequency magnetron sputtering method comprises a first sputtering stage and a second sputtering stage performed sequentially; The sputtering pressure of the first sputtering stage is 0.3-0.5 Pa, the sputtering power is 165-170 W, and the sputtering time is 0.5-1 h; the sputtering pressure of the second sputtering stage is 0.3-0.5 Pa, the sputtering power is 110-115 W, and the sputtering time is 1-1.5 h.

8. The method for preparing the biomedical diamond composite material according to claim 1, characterized in that: Before the surface of the special-shaped structural substrate is covered with the intermediate auxiliary layer, the special-shaped structural substrate is pretreated; The pretreatment process is as follows: the special-shaped structural matrix is ​​cleaned with an acid solution or an alkaline solution, then placed in clean water for ultrasonic vibration for 10-20 minutes, then cleaned with alcohol and wiped dry for later use.

9. The method for preparing the biomedical diamond composite material according to claim 1, characterized in that: After the diamond film layer is deposited, the surface is polished and ground using diamond powder, and then disinfected and sterilized to obtain the biomedical diamond composite material.

10. A biomedical diamond composite material, characterized in that: The biomedical diamond composite material is prepared according to the preparation method of any one of claims 1 to 9.