Deposition method of high-interface-strength DLC film with bonding layer and transition layer
阅读说明：本技术 带有键合层和过渡层的高界面强度dlc薄膜的沉积方法 (Deposition method of high-interface-strength DLC film with bonding layer and transition layer ) 是由 郑锦华 刘青云 李志雄 于 2021-08-19 设计创作，主要内容包括：本发明公开了一种带有键合层和过渡层的高界面强度DLC薄膜的沉积方法,其中,所述键合层为Ar-Si:C:H键合层,所述过渡层为Ar-C:H过渡层,属于表面工程领域。将金属基材研磨抛光洗净后,装卡至DC-PECVD设备中,将沉积室内抽真空；利用Ar气对金属基材表面进行等离子清洗；以四甲基硅烷(TMS)/Ar和C-(2)H-(2)为原料沉积Ar-Si:C:H键合层；以C-(2)H-(2)为碳源,调节沉积偏压以及通入沉积室的Ar、C-(2)H-(2)和H-(2)比例,沉积Ar-C:H过渡层和DLC顶层；沉积结束后,得到带有Ar-Si:C:H键合层和Ar-C:H过渡层的复合DLC薄膜材料。利用本发明能够制备出一种较厚的、与金属基材具有较高结合强度的DLC薄膜材料,在初始500MPa的极高接触应力下,耐磨寿命均超过100万次循环,作为耐磨防护涂层对于减少磨损、延长机械零件的使用寿命具有重要意义。(The invention discloses a deposition method of a high-interface-strength DLC film with a bonding layer and a transition layer, wherein the bonding layer is an Ar-Si: C: H bonding layer, and the transition layer is an Ar-C: H transition layer, and belongs to the field of surface engineering. Grinding, polishing and cleaning the metal substrate, clamping the metal substrate into DC-PECVD equipment, and vacuumizing a deposition chamber; carrying out plasma cleaning on the surface of the metal base material by using Ar gas; tetramethylsilane (TMS)/Ar and C 2 H 2 Depositing an Ar-Si-C-H bonding layer as a raw material; with C 2 H 2 As carbon source, adjusting deposition bias and introducing Ar and C into the deposition chamber 2 H 2 And H 2 The proportion of Ar-C to H transition layer and DLC top layer are deposited;and after the deposition is finished, obtaining the composite DLC film material with the Ar-Si: C: H bonding layer and the Ar-C: H transition layer. The invention can prepare a thicker DLC film material with higher bonding strength with a metal substrate, has the wear-resisting service life of more than 100 ten thousand cycles under the initial extremely high contact stress of 500MPa, and has important significance for reducing wear and prolonging the service life of mechanical parts as a wear-resisting protective coating.)
1. The deposition method of the DLC film with the bonding layer and the transition layer and high interface strength is characterized in that a PECVD chemical vapor deposition technology is adopted, and the deposition method comprises the following steps:
A. firstly, the base material is gradually ground and polished by sand paper, and then is put into acetone for ultrasonic cleaning; then the substrate is clamped into a chemical vapor deposition device, and the pressure inside the deposition chamber is pumped to 5 x 10 by a vacuum pumping device connected with the deposition device-3Pa；
B. Opening an Ar gas valve, introducing the Ar gas into the deposition chamber, and adjusting the opening degree of the Ar gas valve until the internal pressure of the deposition chamber is 3 Pa; then opening a plasma generating source, keeping the internal pressure of the deposition chamber at 3Pa, carrying out plasma etching cleaning on the surface of the base material, removing an oxide layer and pollutants on the surface of the metal base material, and activating the surface of the metal;
C. opening and adjusting the opening of the carbon and silicon gas source air valve to maintain Si (CH) in the deposition chamber3)4、C2H2The pressure of the mixed gas with Ar is 5-6 Pa, the output voltage of a plasma generating source is adjusted, and Ar-S is depositedi, C, H intermediate bonding layer;
D. closing the carbon and silicon gas source valve, and carrying out plasma etching on Ar gas for 5 min;
E. closing the plasma generating source, and adjusting the opening of the Ar gas valve to stabilize the internal pressure of the deposition chamber at 2.5 Pa; opening in sequence C2H2And H2Air valve for introducing Ar and C2H2And H2Introducing the mixture into a deposition chamber according to a certain pressure proportion, keeping the total internal pressure of the deposition chamber to be 17-18 Pa, then opening a plasma generating source, and depositing an Ar-C-H transition layer;
F. turning off the plasma generating source, and turning off Ar and C2H2And H2The air valve stops vacuumizing, the deposition chamber keeps a vacuum state, and the temperature of the workpiece is slowly cooled to room temperature in vacuum;
G. re-vacuuming to 5 × 10-3Pa; opening Ar and C successively2H2And H2Air valve for introducing Ar and C2H2And H2Introducing the mixture into a deposition chamber according to a certain pressure proportion to enable the total internal pressure of the deposition chamber to be about 17-18 Pa; then opening a plasma generating source, and depositing a top DLC diamond-like carbon film;
H. turning off the plasma generating source, and turning off Ar and C2H2And H2And (5) stopping vacuumizing by using an air valve, naturally cooling the deposition system to be below 100 ℃, and finishing the deposition of the high-interface-strength composite diamond-like carbon film.
2. The method for depositing a high interfacial strength DLC film with a bonding layer and a transition layer as claimed in claim 1, wherein: in the step A, the base material is made of metal materials such as carbon steel, tool steel, aluminum alloy, titanium alloy, cast iron, stainless steel and the like.
3. The method for depositing a high interfacial strength DLC film with a bonding layer and a transition layer as claimed in claim 1, wherein: and B, performing plasma etching cleaning on the surface of the base material, wherein the output voltage of the plasma generating source is-2000V during cleaning, and the etching cleaning time is about 30 min.
4. The method for depositing a high interfacial strength DLC film with a bonding layer and a transition layer as claimed in claim 1, wherein: and C, depositing an Ar-Si-C-H bonding layer in the step C, wherein the deposition bias voltage is-1500 to-2000V, and the deposition time is 30 min.
5. The method for depositing a high interfacial strength DLC film with a bonding layer and a transition layer as claimed in claim 1, wherein: step E Ar, C2H2And H2And introducing the mixture into a deposition chamber according to a certain pressure ratio, wherein the ratio of Ar: c2H2：H21: 1.2: and 5, depositing the Ar-C: H transition layer, wherein the deposition bias voltage is-1200 to-1000V, and the deposition time is 1 to 3 hours.
6. The method for depositing a high interfacial strength DLC film with a bonding layer and a transition layer as claimed in claim 1, wherein: and F, performing vacuum cooling to naturally reduce the temperature of the workpiece to room temperature in a vacuum environment, and effectively releasing the residual compressive stress in the bonding layer and the transition layer.
7. The method for depositing a high interfacial strength DLC film with a bonding layer and a transition layer as claimed in claim 1, wherein: step G is carried out by reacting Ar and C2H2And H2And introducing the mixture into a deposition chamber according to a certain pressure ratio, wherein the ratio of Ar: c2H2：H21: 1.5: 6, the deposition bias voltage of the deposited top DLC diamond-like carbon film is-500V to-1300V, and the deposition time is 8 h.
8. The method for depositing a high interfacial strength DLC film with a bonding layer and a transition layer as claimed in claim 1, wherein: the carbon and silicon gas source is Tetramethylsilane (TMS) and C2H2Plasma was formed in an Ar gas atmosphere.
Technical Field
The invention relates to a preparation method of a DLC film material, in particular to a deposition method of a thick composite DLC film with high interface strength and provided with an Ar-Si: C: H bonding layer and an Ar-C: H transition layer.
Background
Diamond-like carbon (DLC) film materials have the characteristics of high hardness, excellent photoelectric property, good biomedical property and the like of diamond, good thermal conductivity and good lubricity of graphite, and thus are widely applied to industry. DLC film materials also have wear resistance similar to diamond and are easier to achieve in terms of manufacturing, and therefore are often used as wear resistant protective coatings to extend the service life of mechanical parts. However, in practical application, the bonding strength of the DLC film and the metal substrate is generally not high, which results in the weakening of the wear-resistant protection function of the coating, and even the poor bonding performance, leading to the film peeling off directly from the substrate and failing. The low bonding strength between the DLC film and the metal substrate is a problem to be solved in the industrial practical application.
The introduction of the bonding layer and the transition layer is one of effective methods for solving the problem of low bonding strength between the DLC film and the metal substrate. The transition layer may be a single transition layer or a gradient transition layer. Common transition layer materials are: ti and its carbide, nitride, Cr and its carbide, nitride, etc. The proper materials and the proper process of the bonding layer and the transition layer can reduce the physical property difference between the base material and the film layer or between two adjacent film layers and establish the chemical bonding effect with the metal base material and between the functional film layers. Meanwhile, in the DLC film deposition process, the residual stress level in the film is effectively regulated and controlled, so that the film-substrate bonding strength is improved, and the method is very beneficial to prolonging the service life of mechanical parts.
To solve the problem of bonding strength between DLC film and metal substrate, for example, Chinese patent No. ZL201710005798.2 discloses a method for preparing a diamond-like coating doped with a metal, such as Cr, Ti or W, provided by a planar metal sputtering targetMetal source, ISE-MS coating equipment, sputtering rate of planar metal sputtering target controlled by controlling power of medium frequency pulse power supply, high purity Ar as main ionization gas, and CH4As a carbon source, a metal bottom layer, a metal carbide transition layer and a metal-doped DLC layer are respectively deposited from the inside to the outside of the substrate. The method improves the film-substrate combination condition by using a bottom layer and a transition layer. Also, for example, chinese patent No. ZL201910942611.0 discloses a method for preparing a DLC film on the surface of super martensitic stainless steel, which comprises placing a hollow glass brick with an explosion-proof opening in a vacuum chamber, placing a metal mesh cage with openings on four sides on the glass brick, allowing electrons to escape to form a loop, placing a substrate inside the mesh cage, preparing a DLC film by PECVD, and further improving the film-substrate bonding force by using a Si/Si-C transition layer before film coating. And Chinese patent No. ZL202011066090.6 discloses an ion-cementation-based gear steel WC-DLC coating and a preparation method thereof, the method firstly carries out nitrogen ion cementation treatment on a gear steel workpiece, improves the atom affinity between the workpiece and a transition layer, and improves the integral bonding performance of the coating by sequentially depositing a Cr transition layer, a CrN transition layer and a WC-DLC coating on the surface of the workpiece by using a PVD method.
The method can improve the bonding strength between the DLC film and the metal substrate, and the film-substrate bonding force can reach about 30N-60N. However, in practical applications, the effect of film thickness on the wear life of the workpiece is also important. At present, the DLC film is applied to a thickness of 2 to 5 μm in many cases, and the applied thickness is less than 10 μm. Generally, an increase in film thickness leads to increased stress in the film and a decrease in film-to-substrate interfacial bond strength. Therefore, how to realize the thickening of the thin film and ensure higher interface bonding strength is an important engineering practical problem.
Disclosure of Invention
The invention aims to provide a deposition method of a high-bonding-strength composite DLC film with an Ar-Si: C: H bonding layer and an Ar-C: H transition layer, so as to realize the thickening of the DLC film and solve the problem of low bonding strength between the DLC film and a metal substrate.
In order to achieve the purpose, the invention adopts the technical scheme that:
a deposition method of a high interfacial strength DLC film with a bonding layer and a transition layer comprises the following steps:
A. firstly, the base material is gradually ground and polished by sand paper, and then is put into acetone for ultrasonic cleaning; then the substrate is clamped into a chemical vapor deposition device, and the pressure inside the deposition chamber is pumped to 5 x 10 by a vacuum pumping device connected with the deposition device-3Pa；
B. Opening an Ar gas valve, introducing the Ar gas into the deposition chamber, and adjusting the opening degree of the Ar gas valve until the internal pressure of the deposition chamber is 3 Pa; then opening a plasma generating source, keeping the internal pressure of the deposition chamber at 3Pa, carrying out plasma etching cleaning on the surface of the base material, removing an oxide layer and pollutants on the surface of the metal base material, and activating the surface of the metal;
C. opening and adjusting the opening of the carbon and silicon gas source air valve to maintain Si (CH) in the deposition chamber3)4、C2H2Adjusting the pressure of the mixed gas of Ar and the gas to be 5-6 Pa, adjusting the output voltage of a plasma generating source, and depositing an Ar-Si-C-H intermediate bonding layer;
D. closing the carbon and silicon gas source valve, and carrying out plasma etching on Ar gas for 5 min;
E. closing the plasma generating source, and adjusting the opening of the Ar gas valve to stabilize the internal pressure of the deposition chamber at 2.5 Pa; opening in sequence C2H2And H2Air valve for introducing Ar and C2H2And H2Introducing the mixture into a deposition chamber according to a certain pressure proportion, keeping the total internal pressure of the deposition chamber to be 17-18 Pa, then opening a plasma generating source, and depositing an Ar-C-H transition layer;
F. turning off the plasma generating source, and turning off Ar and C2H2And H2The air valve stops vacuumizing, the deposition chamber keeps a vacuum state, and the temperature of the workpiece is slowly cooled to room temperature in vacuum;
G. re-vacuuming to 5 × 10-3Pa; opening Ar and C successively2H2And H2Air valve for introducing Ar and C2H2And H2Introducing the mixture into a deposition chamber according to a certain pressure proportion to enable the total internal pressure of the deposition chamber to be about 17-18 Pa; then opening a plasma generating source, and depositing a top DLC diamond-like carbon film;
H. turning off the plasma generating source, and turning off Ar and C2H2And H2And (5) stopping vacuumizing by using an air valve, naturally cooling the deposition system to be below 100 ℃, and finishing the deposition of the high-interface-strength composite diamond-like carbon film.
According to the deposition method of the DLC film with the bonding layer and the transition layer and high interface strength, the base material in the step A is a metal material such as carbon steel, tool steel, aluminum alloy, titanium alloy, cast iron, stainless steel and the like.
According to the deposition method of the DLC film with the bonding layer and the transition layer and high interface strength, the surface of the base material is subjected to plasma etching cleaning in the step B, the output voltage of a plasma generating source is-2000V during cleaning, and the etching cleaning time is about 30 min.
According to the deposition method of the DLC film with the bonding layer and the transition layer and the high interface strength, the Ar-Si-C-H bonding layer is deposited in the step C, the deposition bias voltage is-1500V to-2000V, the deposition time is 30min, and the deposition rate is 2 mu m/hr.
According to the deposition method of the DLC film with the bonding layer and the transition layer and high interfacial strength, Ar and C are added in the step E2H2And H2And introducing the mixture into a deposition chamber according to a certain pressure ratio, wherein the ratio of Ar: c2H2：H21: 1.2: and 5, depositing the Ar-C: H transition layer, wherein the deposition bias voltage is-1200 to-1000V, the deposition time is 1 to 3 hours, and the deposition rate is 2 mu m/hr.
According to the deposition method of the DLC film with the bonding layer and the transition layer and high interface strength, the vacuum cooling in the step F enables the temperature of the workpiece to naturally decrease to room temperature in a vacuum environment, and the residual stress in the bonding layer and the transition layer is effectively released without a forced cooling process.
According to the deposition method of the DLC film with the bonding layer and the transition layer and high interface strength, Ar and C are added in the step G2H2And H2And introducing the mixture into a deposition chamber according to a certain pressure ratio, wherein the ratio of Ar: c2H2：H21: 1.5: 6, the deposition bias voltage of the deposited top DLC diamond-like carbon film is-500V to-1300V, the deposition time is 8h, and the deposition rate is changed along with the input power.
According to the deposition method of the DLC film with the bonding layer and the transition layer and high interfacial strength, the carbon and silicon gas sources are Tetramethylsilane (TMS) and C2H2The ratio is TMS: c2H2With 3:1, plasma was formed in an Ar gas atmosphere.
The invention has the beneficial effects that:
1. according to the invention, the Ar-Si-C-H bonding layer and the Ar-C-H transition layer are added between the DLC film and the metal substrate, so that slow transition of components and structure is realized, structural defects of a large amount of gaps, microcracks, lattice distortion and the like caused by atomic bonding mismatch due to too large structural difference between adjacent materials in a deposition process are avoided, and meanwhile, chemical bonding is formed between the metal substrate and the DLC film, so that the bonding strength of an interface is improved.
2. By adopting a natural cooling mode, the influence of interface shear stress generated by larger thermal expansion coefficient difference among the bonding layer, the transition layer and the metal base material can be greatly reduced, the interface bonding strength between the metal base material and the film material is improved, and the composite DLC film with high bonding strength is obtained.
3. The invention adopts a direct current plasma enhanced chemical vapor deposition (DC-PECVD) method, has no systematic heating process in the film deposition process, has the characteristic of low deposition temperature, has good retention effect on the size and the form and position precision of mechanical parts, and can realize the application on various metal base materials.
4. The film deposition method adopted by the invention has high deposition rate and compact film structure, can meet the requirements of industrial production, and greatly reduces the manufacturing cost of the DLC film.
5. The technical scheme of the invention shows that: in the deposition process of the DLC film, different process parameters, hardness, wear resistance and the like of the DLC film are slightly different, but the structural component difference of the DLC film is not large, the wear resistance service life of the DLC film is more than 100 ten thousand cycles under the initial extremely high contact stress of 500MPa, the DLC film completely meets the actual application requirements, and the optimal process parameters are determined through experimental determination.
6. According to the deposition method of the high-interface-strength DLC film with the bonding layer and the transition layer, the prepared composite DLC film with the Ar-Si-C-H bonding layer and the Ar-C-H transition layer is tightly combined with the metal substrate and among the composite layers, the film structure is continuous and complete, the total thickness of the composite DLC film can reach more than 10 mu m, the thickness of the composite DLC film is much larger than that of the traditional film layer, and the composite DLC film serving as a wear-resistant protective coating is very beneficial to prolonging the service life of mechanical parts.
Drawings
FIG. 1 is a schematic view showing the structure of each layer of the composite DLC film prepared in examples 1 to 4;
FIG. 2 is an SEM image of the composite DLC film prepared in examples 1 to 4, wherein (a) to (d) correspond to examples 1 to 4, respectively;
FIG. 3 shows the measured Raman spectra curves of the composite DLC films prepared in examples 1 to 4, in which-600V, -800V, -1000V and-1200V are the deposition bias voltages of the top DLC film, corresponding to examples 1 to 4, respectively; D. g represents two characteristic peaks of the DLC material: d peak and G peak;
FIG. 4 is an acoustic emission curve of the composite DLC film prepared in example 1 under a 90N load test condition, along with scratch morphology;
FIG. 5 is an acoustic emission curve of the composite DLC film prepared in example 2 under a 90N load test condition, along with scratch morphology;
FIG. 6 is an acoustic emission curve of the composite DLC film prepared in example 3 under a 90N load test condition, along with scratch morphology;
FIG. 7 is an acoustic emission curve of the composite DLC film prepared in example 4 under a load test condition of 90N, along with scratch morphology.
FIG. 8 is a graph showing the friction life curves of the DLC films prepared under different process conditions with an initial contact stress of 500MPa, wherein a to d correspond to examples 1 to 4, respectively.
Detailed Description
The invention is further illustrated, but not limited, by the following examples.
Example 1:
the invention relates to a deposition method of a DLC film with a bonding layer and a transition layer and high interface strength, which comprises the following steps:
A. firstly, grinding and polishing a 45# carbon steel substrate with the diameter of 35mm step by using sand paper, and then putting the substrate into acetone for ultrasonic cleaning; then the substrate is clamped into a chemical vapor deposition device, and the pressure inside the deposition chamber is pumped to 5 x 10 by a vacuum pumping device connected with the deposition device-3Pa；
B. Opening an Ar gas valve, introducing the Ar gas into the deposition chamber, and adjusting the opening degree of the Ar gas valve until the internal pressure of the deposition chamber is 3 Pa; then opening a plasma source, keeping the internal pressure of the deposition chamber at 3Pa, carrying out plasma etching cleaning on the surface of the base material, removing an oxide layer and pollutants on the surface of the metal base material, and activating the surface of the metal;
C. tetramethylsilane (TMS), C was opened and adjusted2H2And the opening degree of an air valve of the Ar gas, keeping the pressure of the mixed gas in the deposition chamber to be 5-6 Pa, adjusting the output voltage value of the plasma source, and depositing an Ar-Si-C-H bonding layer;
D. tetramethylsilane (TMS) and C were turned off2H2Gas valve of gas, Ar gas plasma etching cleaning for 5 min;
E. closing the plasma source, and adjusting the opening of the Ar gas valve to stabilize the internal pressure of the deposition chamber at 2.5 Pa; opening in sequence C2H2And H2Air valve for introducing Ar and C2H2And H2Introducing the mixture into a deposition chamber according to a certain pressure proportion, keeping the total internal pressure of the deposition chamber to be 17-18 Pa, then opening a plasma source, and depositing an Ar-C-H transition layer;
F. turn off the plasma source and turn off Ar, C2H2And H2The air valve stops vacuumizing, the deposition chamber keeps a vacuum state, and the temperature of the workpiece is slowly cooled to room temperature in vacuum;
G. re-vacuuming to 5 × 10-3Pa; opening Ar and C successively2H2And H2Air valve for introducing Ar and C2H2And H2Introducing the mixture into a deposition chamber according to a certain pressure proportion, and keeping the total internal pressure of the deposition chamber to be 17-18 Pa; then opening a plasma source and depositing a top DLC diamond-like carbon film;
H. turn off the plasma source and turn off Ar, C2H2And H2And (5) stopping vacuumizing by using an air valve, naturally cooling the deposition system to be below 100 ℃, and finishing the deposition of the high-interface-strength composite diamond-like carbon film.
And B, performing plasma etching cleaning on the surface of the base material, wherein the output voltage of the plasma source is-2000V during cleaning, and the etching cleaning time is 30 min.
And step C, depositing an Ar-Si-C-H bonding layer, wherein the deposition bias voltage is-1500 to-2000V, the deposition time is 30min, and the deposition rate is 2 mu m/hr.
Step E Ar, C2H2And H2Introducing into a deposition chamber at a certain pressure ratio, Ar and C2H2、H2The deposition bias voltage of the Ar-C: H transition layer is-1200V, the deposition time is 3H, and the deposition rate is 2 mu m/hr.
Step G Ar, C2H2And H2Introducing into a deposition chamber at a certain pressure ratio, Ar and C2H2、H2The deposition bias voltage of the deposited top DLC diamond-like carbon film is-600V, the deposition time is 8h, and the deposition rate is 0.44 mu m/hr.
The structure of the composite DLC film prepared by the implementation method is shown in figure 2(a), and the total thickness of the film is 11.2 mu m; the presence of the D and G peaks in the raman spectrum curve of fig. 3 indicates that the film material is a DLC-like diamond film; the bonding strength of the film and the metal base material is tested by using a coating adhesion automatic scratch tester, the film-base bonding force is 54.6N obtained from the acoustic emission curve and the scratch appearance in the figure 4, the friction life curve in the figure 8 is obtained by using a ball disc type friction tester, after 100 ten thousand cycles, the abrasion depth only reaches about 2.7 mu m, and the composite DLC film is not abraded.
Example 2:
the same as example 1 except that:
and G, depositing the DLC-like carbon film on the top layer, wherein the deposition bias voltage is-800V, and the deposition rate is 0.8 mu m/hr.
The structure of the composite DLC film prepared by the implementation method is shown in figure 2(b), and the total thickness of the film is 14.0 mu m; the presence of the D and G peaks in the raman spectrum curve of fig. 3 indicates that the film material is a DLC-like diamond film; the bonding strength of the film and the metal base material is tested by using a coating adhesion automatic scratch tester, the film-base bonding force is 54.2N obtained from the acoustic emission curve and the scratch appearance in the figure 5, the friction life curve in the figure 8 is obtained by using a ball disc type friction tester, after 100 ten thousand cycles, the abrasion depth only reaches about 3.2 mu m, and the composite DLC film is not abraded.
Example 3:
the same as example 1 except that:
and G, depositing the DLC-like carbon film on the top layer, wherein the deposition bias voltage is-1000V, and the deposition rate is 1.14 mu m/hr.
The structure of the composite DLC film prepared by the implementation method is shown in figure 2(c), and the total thickness of the film is 16.1 mu m; the presence of the D and G peaks in the raman spectrum curve of fig. 3 indicates that the film material is a DLC-like diamond film; the bonding strength of the film and the metal base material is tested by using a coating adhesion automatic scratch tester, the film-base bonding force is 39.4N obtained from the acoustic emission curve and the scratch appearance in the figure 6, the friction life curve in the figure 8 is obtained by using a ball disc type friction tester, after 100 ten thousand cycles, the abrasion depth only reaches about 3.6 mu m, and the composite DLC film is not abraded.
Example 4:
the same as example 1 except that:
and G, depositing the DLC-like carbon film on the top layer, wherein the deposition bias is-1200V, and the deposition rate is 1.16 mu m/hr.
The structure of the composite DLC film prepared by the implementation method is shown in figure 2(d), and the total thickness of the film is 16.3 mu m; the presence of the D and G peaks in the raman spectrum curve of fig. 3 indicates that the film material is a DLC-like diamond film; the bonding strength of the film and the metal base material is tested by using a coating adhesion automatic scratch tester, the film-base bonding force is 33.3N obtained from the acoustic emission curve and the scratch appearance in the figure 7, the friction life curve in the figure 8 is obtained by using a ball disc type friction tester, after 100 ten thousand cycles, the abrasion depth only reaches about 4.0 mu m, and the composite DLC film is not abraded.
The experimental verification results show that the composite DLC film prepared by the invention has larger thickness and higher bonding strength with a metal substrate, and has good application value when being used as a wear-resistant protective coating.
It should be understood that the above-described embodiments are exemplary, are only intended to describe the present invention in detail, and do not limit the content of the present invention. Any changes or substitutions which are not made by the creative efforts shall be covered in the protection scope of the present invention.