Method for preparing graphene diamond hollow drill bit based on lcvd method, drill bit and application

Abstract

The application relates to the field of superhard material processing, and discloses a method for preparing a graphene diamond hollow drill bit based on an LCVD method, the drill bit and application. The method comprises the following steps: base body pretreatment; catalyst loading: immersing the pretreated base body in a nickel nitrate solution, ultrasonic treatment is performed to uniformly adsorb nickel ions on the surface of the base body; then the base body is taken out; graphene growth: placing the catalyst-loaded base body into an LCVD reaction chamber, vacuumizing, then introducing argon and hydrogen, heating the base body, then introducing methane gas, opening a pulse laser, and growing a graphene film on the surface of the base body; diamond deposition: closing the methane gas, introducing hydrogen and methane mixed gas, cooling the base body, opening the pulse laser, and depositing a diamond film on the surface of the graphene film; post-treatment. The method is simple in process, low in cost and high in efficiency, and the prepared drill bit has excellent wear resistance, toughness and service life.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of superhard material processing, and more particularly, to a method for preparing a graphene diamond hollow drill bit on a φ0.6 carbon fiber hollow substrate based on a pulsed laser chemical vapor deposition (LCVD) method. BACKGROUND

[0002] Hard and brittle materials are increasingly widely used in modern industry, and the demand for precision drilling of such materials is growing. However, such materials have the characteristics of high hardness, high brittleness, and low fracture toughness, and traditional drill bits have problems such as easy wear, short service life, and low machining precision when machining hard and brittle materials.

[0003] Diamond, as the hardest material known, has extremely high wear resistance and thermal conductivity, and is an ideal material for preparing high-performance drill bits. However, pure diamond drill bits are brittle, prone to chipping, and expensive. Graphene has excellent mechanical properties and self-lubricating properties, and its combination with diamond can effectively improve the toughness of diamond drill bits and increase their service life. Carbon fiber has high strength, high modulus, and low density, and is an ideal substrate material for preparing lightweight drill bits. However, carbon fiber is inert and difficult to directly deposit a diamond film on its surface.

[0004] Therefore, it is of great significance to develop a new drill bit preparation method that can efficiently prepare graphene diamond composite coatings on ultra-fine carbon fiber hollow substrates while maintaining high strength, high toughness, and high wear resistance. SUMMARY

[0005] The present application aims to provide a method for preparing a graphene diamond hollow drill bit on a φ0.6 carbon fiber hollow substrate by a pulsed laser chemical vapor deposition (LCVD) method. The method is simple, low-cost, and efficient, and the prepared drill bit has excellent wear resistance, toughness, and service life.

[0006] To achieve the above-mentioned application purposes, the present application adopts the following technical solutions:

[0007] In a first aspect, the present application provides a method for preparing a graphene diamond hollow drill bit based on a LCVD method, comprising the following steps:

[0008] Step 1, substrate pretreatment;

[0009] Step 2, catalyst loading: immerse the pretreated substrate in a nickel nitrate solution, and ultrasonically treat to uniformly adsorb nickel ions on the surface of the substrate; then take out the substrate, wash, and dry;

[0010] Step 3, graphene growth: the catalyst-loaded substrate is placed in the LCVD reaction chamber, vacuumized, argon and hydrogen are introduced, the substrate is heated, then methane gas is introduced, the pulsed laser is turned on, and the graphene film is grown on the surface of the substrate;

[0011] Step 4, diamond deposition: the methane gas is turned off, hydrogen and methane mixed gas is introduced, the substrate is cooled, and the pulsed laser is turned on to deposit a diamond film on the surface of the graphene film;

[0012] Step 5, post-processing.

[0013] Further, the substrate pretreatment step specifically includes: the φ0.6 carbon fiber hollow substrate is sequentially cleaned with acetone, ethanol and deionized water by ultrasonic cleaning to remove surface oil stains and impurities; then the substrate is immersed in concentrated nitric acid, and refluxed at 75-85℃ for 1.5-2.5 hours to introduce oxygen-containing functional groups on the surface and improve the surface activity.

[0014] Further, the catalyst loading step specifically includes: the pretreated substrate is immersed in a 0.01 mol / L nickel nitrate solution and ultrasonically treated for 25-35 minutes to uniformly adsorb nickel ions on the surface of the substrate; then the substrate is taken out, washed with deionized water, and dried at 50-60℃.

[0015] Further, the graphene growth step specifically includes: the catalyst-loaded substrate is placed in the LCVD reaction chamber, vacuumized to 10 -3 Pa, argon and hydrogen are introduced at a flow rate of 100 sccm and 50 sccm respectively, the substrate is heated to 800℃, then methane gas is introduced at a flow rate of 10-15 sccm, the pulsed laser is turned on with a wavelength of 1064 nm, a pulse width of 10 ns, a repetition frequency of 10 Hz, and an energy density of 2 J / cm 2 , the graphene film is grown on the surface of the substrate, and the growth time is 20-30 minutes.

[0016] Further, in the graphene growth step, the flow rate of the introduced methane gas changes with time in a gradient manner, the initial flow rate of the introduced methane gas is 10 sccm, then it is linearly increased to 15 sccm within 10 minutes, and then the growth continues for 10-20 minutes.

[0017] Further, the diamond deposition step specifically includes: the methane gas is turned off, hydrogen and methane mixed gas is introduced at a flow rate of 200-250 sccm and 20-40 sccm respectively, the substrate temperature is reduced to 700℃, the pulsed laser is turned on with a wavelength of 1064 nm, a pulse width of 10 ns, a repetition frequency of 10 Hz, and an energy density of 1.5-2.5 J / cm 2Depositing a diamond film on the surface of the graphene film, and the deposition time is 1.5-2 hours.

[0018] Further, in the step of depositing the diamond, a three-stage deposition method is adopted.

[0019] In the first stage, in the first 30 minutes of the diamond deposition process, the hydrogen flow rate is 250 sccm, the methane flow rate is 20 sccm, and the energy density is 1.5 J / cm 2 ;

[0020] In the second stage, in the 30th-60th minute of the diamond deposition process, the hydrogen flow rate is 200 sccm, the methane flow rate is 40 sccm, and the energy density is 2 J / cm 2 ;

[0021] In the third stage, in the 60th-90th minute of the diamond deposition process, the hydrogen flow rate is 250 sccm, the methane flow rate is 20 sccm, and the energy density is 2.5 J / cm 2。

[0022] Further, the step of post-processing specifically comprises: turning off the laser and the gas, cooling the substrate to room temperature under the protection of argon, and taking out the graphene-diamond hollow drill bit.

[0023] In the second aspect, the present application provides a graphene-diamond hollow drill bit prepared by the method of any one of the first aspect, comprising:

[0024] The carbon fiber hollow substrate, the graphene transition layer closely combined with the substrate, and the diamond coating layer located at the outermost layer.

[0025] In the third aspect, the present application provides the use of the graphene-diamond hollow drill bit in the second aspect in the processing of hard and brittle materials.

[0026] In summary, the present application has the following beneficial effects:

[0027] 1. The present application adopts the LCVD method, utilizes the high energy density and rapid heating characteristics of the pulsed laser, realizes the rapid growth of graphene and diamond film at a lower temperature, and reduces the energy consumption and production cost.

[0028] 2. The present application introduces a graphene transition layer on the surface of the carbon fiber substrate, effectively improves the bonding strength of the diamond film and the substrate, and prolongs the service life of the drill bit.

[0029] 3. The graphene-diamond hollow drill bit prepared by the present application has excellent wear resistance, toughness and heat dissipation performance, and is suitable for processing hard and brittle materials such as ceramics, glass, semiconductors, etc. DETAILED DESCRIPTION

[0030] The technical solutions and effects of the present application are further described in detail below in conjunction with examples. It can be understood that the specific examples described herein are merely used to explain the present application and are not limiting to the present application.

[0031] Example 1:

[0032] In this example, a graphene-diamond hollow drill bit is prepared on a φ0.6 carbon fiber hollow substrate based on the LCVD method. The corresponding preparation process includes the following steps:

[0033] Step 1, substrate pretreatment: the φ0.6 carbon fiber hollow substrate is sequentially cleaned with acetone, ethanol, and deionized water by ultrasonic cleaning to remove surface oil stains and impurities; then the substrate is immersed in concentrated nitric acid, and refluxed at 80℃ for 2 hours to introduce oxygen-containing functional groups on the surface and improve the surface activity.

[0034] Step 2, catalyst loading: the pretreated substrate is immersed in a 0.01 mol / L nickel nitrate solution and ultrasonically treated for 30 minutes to allow nickel ions to be uniformly adsorbed on the surface of the substrate; then the substrate is taken out, rinsed with deionized water, and dried at 60℃.

[0035] Step 3, graphene growth: the catalyst-loaded substrate is placed in an LCVD reaction chamber, vacuumed to 10 -3 Pa, argon and hydrogen gas are introduced at flow rates of 100 sccm and 50 sccm respectively, the substrate is heated to 800℃, then methane gas is introduced at a flow rate of 15 sccm, a pulsed laser is turned on, the laser wavelength is 1064 nm, the pulse width is 10 ns, the repetition frequency is 10 Hz, and the energy density is 2 J / cm 2 , a graphene film is grown on the surface of the substrate, and the growth time is 30 minutes.

[0036] Step 4, diamond deposition: turn off the methane gas, introduce hydrogen and methane mixed gas at flow rates of 200 sccm and 20 sccm respectively, reduce the substrate temperature to 700℃, turn on the pulsed laser, the laser wavelength is 1064 nm, the pulse width is 10 ns, the repetition frequency is 10 Hz, and the energy density is 2 J / cm 2 , a diamond film is deposited on the surface of the graphene film, and the deposition time is 2 hours.

[0037] Step 5, post-treatment: turn off the laser and gas, cool the substrate to room temperature under argon protection, and take out the graphene-diamond hollow drill bit.

[0038] Example 2:

[0039] In this example, graphene diamond hollow drill bit is prepared on the basis of LCVD method on φ0.6 carbon fiber hollow substrate, and the corresponding preparation process includes the following steps:

[0040] Step 1, substrate pretreatment: the φ0.6 carbon fiber hollow substrate is sequentially cleaned with acetone, ethanol and deionized water by ultrasonic, and the surface oil stains and impurities are removed; then the substrate is immersed in concentrated nitric acid, and refluxed at 80°C for 2 hours, and oxygen-containing functional groups are introduced on the surface to improve the surface activity.

[0041] Step 2, catalyst loading: the pretreated substrate is immersed in 0.01 mol / L nickel nitrate solution, and ultrasonic treated for 30 minutes, so that the nickel ions are uniformly adsorbed on the surface of the substrate; then the substrate is taken out, washed with deionized water, and dried at 60°C.

[0042] Step 3, graphene growth: the catalyst-loaded substrate is placed in the LCVD reaction chamber, vacuumed to 10 -3 Pa, argon and hydrogen gas are introduced, the flow rates are 100 sccm and 50 sccm respectively, the substrate is heated to 800°C; then methane gas is introduced, the flow rate is 10 sccm, the pulse laser is turned on, the laser wavelength is 1064 nm, the pulse width is 10 ns, the repetition frequency is 10 Hz, and the energy density is 2 J / cm 2 , graphene thin film is grown on the surface of the substrate, and the growth time is 20 minutes.

[0043] Step 4, diamond deposition: turn off the methane gas, introduce hydrogen and methane mixed gas, the flow rates are 200 sccm and 20 sccm respectively, reduce the substrate temperature to 700°C; turn on the pulse laser, the laser wavelength is 1064 nm, the pulse width is 10 ns, the repetition frequency is 10 Hz, and the energy density is 2 J / cm 2 , diamond thin film is deposited on the surface of the graphene thin film, and the deposition time is 2 hours.

[0044] Step 5, post-treatment: turn off the laser and gas, cool the substrate to room temperature under argon protection, and take out the graphene diamond hollow drill bit.

[0045] Example 3:

[0046] In this example, graphene diamond hollow drill bit is prepared on the basis of LCVD method on φ0.6 carbon fiber hollow substrate, and the corresponding preparation process includes the following steps:

[0047] Step 1, substrate pretreatment: the φ0.6 carbon fiber hollow substrate is sequentially cleaned with acetone, ethanol and deionized water by ultrasonic, and the surface oil stains and impurities are removed; then the substrate is immersed in concentrated nitric acid, and refluxed at 80°C for 2 hours, and oxygen-containing functional groups are introduced on the surface to improve the surface activity.

[0048] Step 2, catalyst loading: immerse the pretreated substrate into a 0.01 mol / L nickel nitrate solution, and ultrasonically treat for 30 minutes to make the nickel ions uniformly adsorbed on the surface of the substrate; then take out the substrate, rinse it clean with deionized water, and dry it at 60°C.

[0049] Step 3, graphene growth: place the catalyst-loaded substrate into an LCVD reaction chamber, vacuumize it to 10 -3 Pa, introduce argon and hydrogen gas at a flow rate of 100 sccm and 50 sccm respectively, heat the substrate to 800°C, then introduce methane gas at a flow rate of 15 sccm, and turn on the pulsed laser with a wavelength of 1064 nm, a pulse width of 10 ns, a repetition frequency of 10 Hz, and an energy density of 2 J / cm 2 , to grow a graphene film on the surface of the substrate for 30 minutes.

[0050] Step 4, diamond deposition: turn off the methane gas, introduce hydrogen and methane mixed gas at a flow rate of 250 sccm and 40 sccm respectively, reduce the substrate temperature to 700°C, turn on the pulsed laser with a wavelength of 1064 nm, a pulse width of 10 ns, a repetition frequency of 10 Hz, and an energy density of 2 J / cm 2 , to deposit a diamond film on the surface of the graphene film for 2 hours.

[0051] Step 5, post-processing: turn off the laser and gas, cool the substrate to room temperature under argon protection, and take out the graphene-diamond hollow drill bit.

[0052] Example 4:

[0053] In this example, a graphene-diamond hollow drill bit is prepared on a φ0.6 carbon fiber hollow substrate based on the LCVD method, and the corresponding preparation process includes the following steps:

[0054] Step 1, substrate pretreatment: ultrasonically clean the φ0.6 carbon fiber hollow substrate with acetone, ethanol, and deionized water in sequence to remove surface oil stains and impurities; then immerse the substrate in concentrated nitric acid, reflux it at 80°C for 2 hours to introduce oxygen-containing functional groups on the surface and improve the surface activity.

[0055] Step 2, catalyst loading: immerse the pretreated substrate into a 0.01 mol / L nickel nitrate solution, and ultrasonically treat for 30 minutes to make the nickel ions uniformly adsorbed on the surface of the substrate; then take out the substrate, rinse it clean with deionized water, and dry it at 60°C.

[0056] Step 3, graphene growth: place the catalyst-loaded substrate into an LCVD reaction chamber, vacuumize it to 10-3 Pa, argon and hydrogen gas were introduced with flow rates of 100 sccm and 50 sccm, respectively, and the substrate was heated to 800℃; then methane gas was introduced, the flow rate of the introduced methane gas was changed with time in a gradient manner, the initial flow rate of the introduced methane gas was 10 sccm, then it was linearly increased to 15 sccm within 10 minutes, and then the growth was continued for 20 minutes, in the process, a pulsed laser was turned on, the wavelength of the laser was 1064 nm, the pulse width was 10 ns, the repetition frequency was 10 Hz, and the energy density was 2 J / cm 2 A graphene film was grown on the surface of the substrate, and the total growth time was 30 minutes.

[0057] Step 4, diamond deposition: the methane gas was turned off, and hydrogen and methane mixed gas was introduced with flow rates of 200 sccm and 20 sccm, respectively, and the substrate temperature was reduced to 700℃; a pulsed laser was turned on, the wavelength of the laser was 1064 nm, the pulse width was 10 ns, the repetition frequency was 10 Hz, and the energy density was 2 J / cm 2 A diamond film was deposited on the surface of the graphene film, and the deposition time was 2 hours.

[0058] Step 5, post-processing: the laser and the gas were turned off, the substrate was cooled to room temperature under the protection of argon, and then the graphene-diamond hollow drill bit was obtained.

[0059] Example 5:

[0060] In this example, a graphene-diamond hollow drill bit was prepared on a φ0.6 carbon fiber hollow substrate based on the LCVD method, and the corresponding preparation process included the following steps:

[0061] Step 1, substrate pretreatment: the φ0.6 carbon fiber hollow substrate was sequentially ultrasonically cleaned with acetone, ethanol, and deionized water to remove surface oil stains and impurities; then the substrate was immersed in concentrated nitric acid, and refluxed at 80℃ for 2 hours to introduce oxygen-containing functional groups on the surface and improve the surface activity.

[0062] Step 2, catalyst loading: the pretreated substrate was immersed in a 0.01 mol / L nickel nitrate solution, and ultrasonically treated for 30 minutes to uniformly adsorb nickel ions on the surface of the substrate; then the substrate was taken out, washed with deionized water, and dried at 60℃.

[0063] Step 3, graphene growth: the catalyst-loaded substrate was placed in an LCVD reaction chamber, vacuumed to 10 -3Pa, argon and hydrogen gas were introduced at a flow rate of 100 sccm and 50 sccm respectively, and the substrate was heated to 800℃; then methane gas was introduced, the flow rate of the introduced methane gas was changed with time in a gradient manner, the initial flow rate of the introduced methane gas was 10 sccm, then it was linearly increased to 15 sccm within 10 minutes, and then the growth was continued for 20 minutes, in the process, the pulsed laser was turned on, the wavelength of the laser was 1064 nm, the pulse width was 10 ns, the repetition frequency was 10 Hz, and the energy density was 2 J / cm 2 The graphene film was grown on the surface of the substrate, and the total growth time was 30 minutes.

[0064] Step 4, diamond deposition: turn off the methane gas, introduce hydrogen and methane mixed gas, and reduce the substrate temperature to 700℃; turn on the pulsed laser, the wavelength of the laser is 1064 nm, the pulse width is 10 ns, the repetition frequency is 10 Hz, and the energy density is 1.5-2.52 J / cm 2 The diamond film was deposited on the surface of the graphene film, and the deposition time was 2 hours.

[0065] In the step of depositing the diamond, a three-stage deposition method was used:

[0066] In the first stage, within the first 30 minutes of the diamond deposition process, the hydrogen flow rate was 250 sccm, the methane flow rate was 20 sccm, and the energy density was 1.5 J / cm 2 ;

[0067] In the second stage, within the 30th-60th minute of the diamond deposition process, the hydrogen flow rate was 200 sccm, the methane flow rate was 40 sccm, and the energy density was 2 J / cm 2 ;

[0068] In the third stage, within the 60th-90th minute of the diamond deposition process, the hydrogen flow rate was 250 sccm, the methane flow rate was 20 sccm, and the energy density was 2.5 J / cm 2 .

[0069] Step 5, post-processing: turn off the laser and the gas, cool the substrate to room temperature under the protection of argon, and then take out the graphene-diamond hollow drill bit.

[0070] Comparative Example 1:

[0071] The present example gives a method for preparing a graphene-diamond hollow drill bit, which differs from Example 1 in that Step 3 is omitted, and the diamond film is directly deposited on the carbon fiber substrate.

[0072] Comparative Example 2:

[0073] The present example gives a method for preparing graphene diamond hollow drill bit, the preparation method, and the difference of example 1 is that: in step 3, the graphene film is grown by using conventional CVD method instead of pulse laser.

[0074] Performance test

[0075] The performance of the drill bits prepared in examples 1-5 and comparative examples 1-2 was tested, and the results are shown in Table 1.

[0076] Table 1 Performance test results

[0077] Diamond film thickness (pm) Graphene film thickness (nm) Bonding strength (MPa) Wear resistance (mm 3 / N·m) Service life (h) Example 1 10 5 150 1.2 x 10 -6 ]]> 50 Example 2 8 3 140 1.5 x 10 -6 ]]> 45 Example 3 12 7 160 1.1 x 10 -6 ]]> 55 Example 4 8 4 170 1.0 x 10 -6 ]]> 60 Example 5 8 4 180 1.0 x 10 -6 ]]> 65 Comparative Example 1 10 - 80 2.0 x 10 -6 ]]> 20 Comparative Example 2 10 5 100 1.8 x 10 -6 ]]> 30

[0078] In combination with examples 1-3 and comparative examples 1-2, and in combination with the data in Table 1, it can be seen that the graphene diamond hollow drill bit prepared in examples 1-3 has excellent bonding strength, wear resistance and service life, which is significantly better than comparative examples 1-2. This shows that the present application introduces a graphene transition layer on the surface of the carbon fiber substrate, and deposits a diamond film by LCVD method, which effectively improves the bonding strength of the diamond film and the substrate, and improves the service life of the drill bit.

[0079] Further, in combination with examples 1, 4, 5, and in combination with the data in Table 1, it can be seen that in example 4 of the present application, by controlling the gradient change of the flow of methane gas, the bonding strength, wear resistance and service life of the graphene diamond hollow drill bit are further improved; and in example 5, on the basis of example 4, diamond is deposited by a three-stage deposition method, which further improves the bonding strength, wear resistance and service life of the graphene diamond hollow drill bit.

[0080] The present application has the advantages that the method for preparing graphene diamond hollow drill bit by LCVD method is simple, low cost and high efficiency, and the prepared drill bit has excellent wear resistance, toughness and service life, is suitable for processing hard and brittle materials, and has broad application prospects.

[0081] The present embodiment is only an explanation of the present application, and is not a limitation of the present application. Those skilled in the art can make modifications to the present embodiment without creative contribution after reading the present specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A method for preparing a graphene diamond hollow drill bit based on LCVD method, characterized in that, The method comprises the following steps: Step 1, substrate pretreatment, the substrate is a carbon fiber hollow substrate; Step 2, catalyst loading: the pretreated substrate is immersed in a nickel nitrate solution, and ultrasonic treatment is performed to uniformly adsorb nickel ions on the surface of the substrate; then the substrate is taken out, washed, and dried; Step 3, graphene growth: the catalyst-loaded substrate was put into the LCVD reaction chamber, vacuumed to 10 -3 Pa, argon and hydrogen were introduced at a flow rate of 100 sccm and 50 sccm respectively, and the substrate was heated to 800℃; then, methane gas was introduced at a flow rate of 10-15 sccm, and a pulsed laser was turned on, with a wavelength of 1064 nm, a pulse width of 10 ns, a repetition frequency of 10 Hz, and an energy density of 2 J / cm 2 The graphene film was grown on the surface of the substrate, and the growth time was 20-30 minutes. The flow rate of the introduced methane gas is changed in a gradient manner with time, the initial flow rate of the introduced methane gas is 10 sccm, then the flow rate is linearly increased to 15 sccm within 10 minutes, and then the growth is continued for 10-20 minutes; Step 4, diamond deposition: close the methane gas, and introduce hydrogen and methane mixed gas, the flow rate is 200-250 sccm and 20-40 sccm respectively, and the substrate temperature is reduced to 700 DEG C; open the pulsed laser, the laser wavelength is 1064 nm, the pulse width is 10 ns, the repetition frequency is 10 Hz, and the energy density is 1.5-2.5 J / cm 2 Depositing a diamond film on the surface of the graphene film, and the deposition time is 1.5-2 hours; Step 5, post-treatment.

2. The method of claim 1, wherein the graphene diamond hollow drill bit is prepared based on the LCVD method. The step of substrate pretreatment specifically comprises: the φ0.6 carbon fiber hollow substrate is sequentially cleaned with acetone, ethanol, and deionized water by ultrasonic cleaning to remove surface oil stains and impurities; then the substrate is immersed in concentrated nitric acid, and reflux treatment is performed at 75-85 DEG C for 1.5-2.5 hours to introduce oxygen-containing functional groups on the surface and improve the surface activity.

3. The method of manufacturing a graphene diamond hollow drill bit based on LCVD process according to claim 1, wherein, The step of catalyst loading specifically comprises: the pretreated substrate is immersed in a 0.01 mol / L nickel nitrate solution, and ultrasonic treatment is performed for 25-35 minutes to uniformly adsorb nickel ions on the surface of the substrate; then the substrate is taken out, washed with deionized water, and dried at 50-60 DEG C.

4. The method of claim 1, wherein the graphene diamond hollow drill bit is prepared based on the LCVD method. In the step of diamond deposition, a three-stage deposition method is adopted. In the first stage, for the first 30 minutes of the diamond deposition process, the hydrogen flow rate was 250 seem, the methane flow rate was 20 seem, and the energy density was 1.5 J / cm 2 ; In the second stage, the hydrogen flow rate is 200 seem, the methane flow rate is 40 seem, and the energy density is 2 J / cm2 during the 30th to 60th minute of the diamond deposition process 2 ; In the third stage, the hydrogen flow rate was 250 seem, the methane flow rate was 20 seem, and the energy density was 2.5 J / cm2 from 60 to 90 minutes of the diamond deposition process 2 .

5. The method of manufacturing a graphene diamond hollow drill bit based on LCVD process according to claim 1, wherein, The step of post-treatment specifically comprises: the laser and the gas are turned off, the substrate is cooled to room temperature under the protection of argon, and then the graphene diamond hollow drill bit is obtained after the substrate is taken out.

6. A graphene diamond hollow drill bit, characterized by, The graphene diamond hollow drill bit is prepared by the method according to any one of claims 1-5, and characterized in that it comprises: The carbon fiber hollow substrate, the graphene transition layer closely combined with the substrate, and the diamond coating layer located at the outermost layer.

7. Use of the graphene diamond hollow drill bit according to claim 6 in the machining of hard and brittle materials.