CN110438465A - Metal base surface anti scuffing protective coating and the preparation method and application thereof - Google Patents

Abstract

The invention discloses an anti-corrosion protective coating on the surface of a metal substrate, a preparation method and application thereof. The coating includes a Ti transition layer, a TiC _x gradient layer, a first DLC layer, a TiC _x /Ti/TiC _x /DLC alternate layer stack and The top layer, the _TiCx /Ti/ _TiCx /DLC alternate layer stack is formed by alternately stacking a _TiCx /Ti/ _TiCx sandwich layer and a second DLC layer, and the _TiCx /Ti/ _TiCx sandwich layer includes two TiC An _x layer and a Ti layer disposed between the two TiC _x layers, the top layer includes a third DLC layer, and the value of X in the TiC _x ranges from 0.8 to 1.3. The anti-corrosion protective coating provided by the invention adopts the structure of "alternating multi-layer + interface gradient + top layer extension", so that the coating has good comprehensive mechanical properties, and has excellent corrosion resistance and abrasion resistance. At the same time, the anti-wear protective coating can still maintain a good friction-reducing and lubricating effect within a certain period of time after being worn through, showing high wear-resistant failure tolerance.

Description

Anti-corrosion protective coating on metal substrate surface and its preparation method and application

technical field

The invention belongs to the technical field of surface treatment of mechanical parts, in particular relates to an anti-abrasion protective coating on the surface of a metal substrate and its preparation method and application, in particular to a seawater pump impeller and friction pair parts with long service life and high damage tolerance on the surface Erosion resistant protective coating and its preparation method and application.

Background technique

my country's exploration, development and utilization of marine resources are increasingly strengthened. As a new technology emerging to adapt to marine development, seawater hydraulic transmission technology with seawater as the working fluid has been gradually applied to the sea due to its high safety, small compression coefficient, low use and maintenance costs, green and pollution-free, and many other advantages. Salvage and salvage, marine resources survey, offshore oil and gas exploitation and many other marine engineering fields.

As the core power component of seawater hydraulic transmission system, the development and research of high-performance seawater pump is the key to promote the development of seawater hydraulic transmission technology. At the same time, seawater pumps operate in seawater environments with poor lubricity due to the existence of various motion friction pairs such as plunger-cylinder bore, sliding shoe-swash plate, valve plate-floating plate, and high-speed and heavy-load operating conditions. The friction pair is prone to failure due to corrosion, wear and other reasons, which seriously affects its working efficiency and service life. Through the analysis of the failure mode and failure mechanism of seawater pumps, it is found that the corrosion of materials and the friction and wear characteristics of materials at key friction pairs are the key factors affecting the reliability of seawater pumps.

In order to solve the corrosion and wear failure problems faced by related components of seawater pumps, the selection of new anti-wear and corrosion-resistant materials and the surface protection treatment of existing materials are two main methods. In terms of selecting new wear-resistant and corrosion-resistant materials, patent CN101519749A discloses a cast iron material with 18-20wt% nickel, 8-10wt% copper, 5-6wt% chromium, 4-5wt% titanium, and iron balance. After the seawater pump impeller made of material is placed in the seawater infiltration well containing fine sand particles and continuously worked for 2000 hours, the surface corrosion and wear amount is less than 1/10 of the existing cast iron impeller, and the corrosion resistance and wear resistance performance are significantly enhanced. In addition, the patent CN101476078A proposes a manufacturing method of a large seawater pump shaft with good thermoplasticity and high product recovery rate. The selected 00Cr25Ni7Mo3WCuN super duplex stainless steel has excellent resistance to seawater and halogen medium corrosion.

Surface protection treatment can endow parts with excellent surface characteristics without changing the material and forming performance of parts, and is an effective technical means to improve the service performance and life of parts. The patent CN104847685A proposes to solve the corrosion problem of seawater pumps by coating the iron-based alloy impeller with a chromium oxide-based ceramic material layer, and coating the inner and outer surfaces of the aluminum alloy pump with silicon carbide and silicon oxide-based ceramic material layers. In addition, the patent CN108251833A proposes a method of using ultra-high-speed laser cladding technology to prepare the surface of the nuclear power seawater pump shaft. This method can quickly and accurately prepare the surface of the nuclear power seawater pump shaft with good flatness, thickness 0.10 ~ 0.45mm, Defect-free cobalt based corrosion and wear resistant coating. Although the above-mentioned surface coating can significantly improve the anti-corrosion and wear-resisting performance of seawater pump parts, the preparation process often experiences high temperature, which easily reduces the mechanical properties of the parts. At the same time, the prepared coating is thick and has a rough surface, which requires high assembly precision. Parts with small fit gaps need to be reserved for processing or post-polishing, which greatly increases the manufacturing cost.

Contents of the invention

The main purpose of the present invention is to provide a long-life, high damage-tolerant anti-corrosion protective coating on the surface of a metal substrate and its preparation method and application, so as to overcome the deficiencies in the prior art.

In order to realize the aforementioned object of the invention, the technical solutions adopted in the present invention include:

An embodiment of the present invention provides an anti-corrosion protective coating on the surface of a metal substrate, which includes a Ti transition layer, a TiC _x gradient layer, a first DLC layer, and an alternating TiC _x /Ti/TiC _x /DLC layer formed on the surface of the metal base in sequence. A stacked layer and a top layer, wherein the TiC _x /Ti/TiC _x /DLC alternately stacked layer is formed by alternately stacking a TiC _x /Ti/TiC _x sandwich layer and a second DLC layer, and the TiC _x /Ti/TiC _x sandwich The layer includes two _TiCx layers and a Ti layer arranged between the two _TiCx layers, the top layer includes a third DLC layer, and the value of _X in the TiCx ranges from 0.8 to 1.3.

Embodiments of the present invention also provide the preparation method of the aforementioned anti-wear protective coating, which includes:

S1. Pretreating the surface of the metal substrate;

S2. Using DC magnetron sputtering technology to sequentially deposit Ti transition layer and TiC _x gradient layer on the surface of the metal substrate, and then using linear ion source technology to deposit the first DLC layer on the surface of the TiC _x gradient layer;

S3. Depositing a TiC _x /Ti/TiC _x sandwich layer on the surface of the first DLC layer using DC magnetron sputtering technology, and using a linear ion source technology to deposit the second DLC layer, and making the TiC _x /Ti/TiC _x sandwich layer layer and the second DLC layer are stacked alternately to form TiC _x /Ti/TiC _x /DLC alternate layers;

S4. Depositing a third DLC layer on the alternating layer of TiC _x /Ti/TiC _x /DLC by using linear ion source technology to form the anti-corrosion protective coating.

The embodiment of the present invention also provides the application of the anti-corrosion protective coating on the surface of the metal substrate in the field of surface protection of seawater pump moving parts.

Compared with the prior art, the advantages of the present invention include:

(1) The coating adopts an alternately deposited multi-layer structure, which is beneficial to reduce the internal stress of the film (the residual stress is -1.2 to -1.6GPa), and to improve the bonding strength of the film base (the bonding strength with the stainless steel substrate is 10 to 15N), and at the same time It is beneficial to suppress the generation of penetrating defects, prolong the diffusion path of the corrosive medium, and improve the corrosion resistance of the coating (the self-corrosion current density in 3.5wt% NaCl solution is as low as 3~5×10 ^-10 A cm ^-2 , which is lower than that of the stainless steel substrate reduced by more than an order of magnitude);

(2) The gradient structure of Ti-TiC _x -DLC is conducive to improving the interface fit and bonding strength of the coating, endowing it with excellent overall mechanical properties (nanometer hardness 11-16GPa, elastic modulus 139-157GPa, fracture toughness 1.4 ~1.6MPa·m ^1/2 );

(3) The thickened DLC layer on the top layer is conducive to improving the mechanical strength of the coating and endowing it with long-life anti-friction lubrication ability (under 5N load in 3.5wt%NaCl solution and Φ6mm Al ₂ O ₃ ceramic ball pair When the coefficient of friction <0.10, life> 36.5h). Therefore, the prepared multilayer coating has excellent mechanical properties and exhibits high corrosion and abrasion resistance in seawater environment, showing great application potential in the field of surface protection of seawater pump moving parts.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is the cross-sectional structural representation of coating of the present invention;

Fig. 2 is the cross-sectional SEM photo of the coating prepared in embodiment 1;

Fig. 3 is the polarization resistance change curve that the coating prepared in embodiment 1 is soaked in 3.5wt%NaCl at room temperature for 63 days;

Fig. 4 is the OCP and COF change curve of the coating prepared in embodiment 1 under the abrasion test 36.5 h under the load of 5N in 3.5wt%NaCl;

Fig. 5 is the SEM photograph of the wear scar surface after the abrasion test 12h of the coating prepared in embodiment 2 under the 5N load in 3.5wt%NaCl;

Fig. 6 is the OCP and COF change curve of the coating prepared in embodiment 2 under the abrasion test 12 h under 20N load in 3.5wt%NaCl;

Fig. 7 is the SEM photo of the wear scar surface after the wear test 12h of Ti/DLC coating prepared in comparative example 1 under 5N load in 3.5wt%NaCl;

Fig. 8 is an SEM photo of the wear scar surface after the TiC _x /DLC coating prepared in Comparative Example 2 was subjected to an abrasion test under a 5N load in 3.5wt% NaCl for 12 hours.

Detailed ways

In view of the deficiencies in the prior art, the inventor of this case has been able to propose the technical solution of the present invention through long-term research and a large amount of practice, and the technical solution, its implementation process and principle will be further explained as follows.

One aspect of the embodiments of the present invention provides an anti-corrosion protective coating on the surface of a metal substrate, which includes a Ti transition layer, a TiC _x gradient layer, a first DLC layer, TiC _x /Ti/TiC _x formed sequentially on the surface of the metal base /DLC alternately stacked layer and top layer, wherein, the TiC _x /Ti/TiC _x /DLC alternately stacked layer is formed by alternately stacking TiC _x /Ti/TiC _x sandwich layers and the second DLC layer, and the TiC _x /Ti/Ti/ The _TiCx sandwich layer comprises two _TiCx layers and a Ti layer disposed between said two _TiCx layers, said top layer comprising a third DLC layer _TiCx .

Further, the alternately stacked TiC _x /Ti/TiC _x /DLC layer includes 4 to 7 alternately stacked periodic layers, wherein each alternately stacked periodic layer includes a TiC _x /Ti/TiC _x sandwich layer and a DLC layer.

Further, the TiC _x layer is a gradient layer between the TiC layer and the DLC layer.

Further, the thickness of the anti-wear protective coating is 1.5-2.8 μm.

Further, the thickness of the third DLC layer is 200-300 nm.

Further, the substrate includes a stainless steel substrate; preferably, the substrate includes 316L stainless steel and/or S32750 stainless steel.

An aspect of the embodiments of the present invention also provides the preparation method of the aforementioned anti-wear protective coating, which includes:

S1. Pretreating the surface of the metal substrate;

S2. Using DC magnetron sputtering technology to sequentially deposit Ti transition layer and TiC _x gradient layer on the surface of the metal substrate, and then using linear ion source technology to deposit the first DLC layer on the surface of the TiC _x gradient layer;

S3. Depositing a TiC _x /Ti/TiC _x sandwich layer on the surface of the first DLC layer using DC magnetron sputtering technology, and using a linear ion source technology to deposit the second DLC layer, and making the TiC _x /Ti/TiC _x sandwich layer layer and the second DLC layer are stacked alternately to form TiC _x /Ti/TiC _x /DLC alternate layers;

S4. Depositing a third DLC layer on the alternating layer of TiC _x /Ti/TiC _x /DLC by using linear ion source technology to form the anti-corrosion protective coating.

In some more specific embodiments, the preparation method includes:

(1) Pre-treat the surface of the substrate: use 120# to 3000# SiC metallographic sandpaper to polish the metal substrate sequentially, and then use Al ₂ O ₃ abrasive paste with a particle size of 0.2 to 0.3 μm to polish the metal substrate for 10 ~15min;

Clean the polished metal substrate sequentially with acetone, ethanol, and deionized water for 5 to 15 minutes, and dry it with cold air;

Place the metal substrate in the vacuum chamber for film deposition, evacuate to 2.0×10 ^-5 Torr, then heat the chamber at 120-150°C, then pass argon gas with a gas flow rate of 30-36 sccm into the vacuum chamber, and turn on the linear The ion source and the pulse bias voltage perform bias etching and cleaning on the substrate for 30-45 minutes, wherein the linear ion source current and the pulse bias voltage are 0.20-0.25A and -200--250V respectively.

(2) Using DC magnetron sputtering technology to deposit Ti transition layer and TiC _x gradient layer sequentially on the surface of the metal substrate, and then using linear ion source technology to deposit the first DLC layer on the surface of TiC _x gradient layer;

Preferably, the conditions for depositing the Ti transition layer include: a Ti target, an argon flow rate of 48-52 sccm, an acetylene flow rate of 0 sccm, a deposition time of 9-10 minutes, a DC magnetron sputtering source current and a pulse bias voltage of 3.0A and -150-sccm, respectively. -200V; the conditions for depositing a TiC _x gradient layer include: Ti target, argon gas flow rate of 48-52 sccm, acetylene flow rate of 4.8-5.2 sccm, deposition time of 9-10 min, DC magnetron sputtering source current and pulse bias voltage of 3.0A and -150~-200V; the conditions for depositing the first DLC layer include: acetylene flow rate 36~40sccm, deposition time 12~18min, linear ion source current and pulse bias voltage 0.2A and -150~-200V respectively.

(3) Deposit a TiC _x /Ti/TiC _x sandwich layer on the surface of the first DLC layer by using DC magnetron sputtering technology, and deposit the second DLC layer by using linear ion source technology, and make the TiC _x /Ti/TiC _x The sandwich layer and the second DLC layer are stacked alternately to form an alternating layer of TiC _x /Ti/TiC _x /DLC.

Preferably, the conditions for depositing the TiC _x layer in the TiC _x /Ti/TiC _x sandwich layer include: Ti target, argon gas flow rate of 48-52 sccm, acetylene flow rate of 4.8-5.2 sccm, deposition time of 6-9 minutes, DC magnetron sputtering The source current and pulse bias voltage are 3.0A and -150~-200V respectively; the conditions for depositing the Ti layer in the _TiCx /Ti/ _TiCx sandwich layer include: Ti target, argon gas flow rate 48~52sccm, acetylene flow rate 0sccm, deposition time 6~9min, DC magnetron sputtering source current and pulse bias voltage are 3.0A and -150~-200V respectively; the conditions for depositing the second DLC layer include: acetylene flow rate 36~40sccm, deposition time 12~18min, linear ion source The current and pulse bias are 0.2A and -150~-200V, respectively.

Preferably, the alternating stacking period of the TiC _x /Ti/TiC _x sandwich layer deposited by DC magnetron sputtering technology and the DLC layer deposited by linear ion source technology is 4-7.

(4) Depositing the third DLC layer on the alternating layers of TiC _x /Ti/TiC _x /DLC by using linear ion source technology to form the anti-corrosion protective coating.

Preferably, the conditions for depositing the third DLC layer include: acetylene flow rate of 36-40 sccm, deposition time of 24-36 min, linear ion source current and pulse bias voltage of 0.2A and -150-200V respectively.

An aspect of the embodiments of the present invention also provides the use of the aforementioned anti-corrosion protective coating on the surface of the metal substrate for anti-corrosion of the moving parts of the seawater pump.

The technical solutions of the present invention will be further described below through specific embodiments. It is easy for those skilled in the art to understand that the embodiments are only to help understand the present invention, and should not be regarded as a specific limitation to the present invention.

Example 1:

In this embodiment, the base material is AISI 316L austenitic stainless steel, and the structure of the coating is shown in FIG. 1 , wherein the total thickness of the coating is 1.6 μm.

The coating preparation steps on the above-mentioned 316L surface are as follows:

Step 1: Use 120# to 3000# SiC metallographic sandpaper to polish the 316L substrate in sequence, and then use Al ₂ O ₃ abrasive paste with a particle size of 0.2 to 0.3 μm to perform metallographic polishing on the stainless steel substrate for 15 minutes;

Step 2: Place the polished 316L stainless steel substrate in acetone, ethanol and deionized water in sequence for ultrasonic cleaning for 10 minutes, and then dry it with cold air for later use;

Step 3: Place the 316L stainless steel substrate in the vacuum chamber for film deposition, vacuumize to 2.0×10 ^-5 Torr with a mechanical pump and a turbomolecular pump successively, then turn on the heater and set the heating temperature to 150°C. Introduce high-purity argon gas with a flow rate of 36 sccm into the vacuum chamber, turn on the linear ion source and pulse bias voltage, set the linear ion source current and pulse bias voltage to 0.2A and -200V respectively, and perform bias etching cleaning on the 316L stainless steel substrate 30min;

Step 4: Feed high-purity argon gas with a flow rate of 50 sccm and high-purity acetylene with a flow rate of 5 sccm (acetylene is only fed in when the TiC _x layer is deposited), turn on the DC magnetron sputtering source and pulse bias, and set the DC magnetron respectively The sputtering source current and pulse bias are 3.0A and -150V, using DC magnetron sputtering technology to sputter on the surface of the stainless steel substrate for 9min+9min to prepare Ti transition layer and TiC _x gradient layer; , turn on the linear ion source and pulse bias voltage, set the linear ion source current and pulse bias voltage to 0.2A and -150V respectively, and use the linear ion source technology to deposit 12min on the TiC _x gradient layer to prepare the first DLC layer;

Step 5: feed high-purity argon gas with a flow rate of 50 sccm and high-purity acetylene with a flow rate of 5 sccm (acetylene is only fed in when the TiC _x layer is deposited), turn on the DC magnetron sputtering source and pulse bias, and set the DC magnetron The sputtering source current and pulse bias are 3.0A and -150V, and the TiC _x /Ti/TiC _x layer is prepared by sputtering on the DLC layer for 6min+6min+6min using DC magnetron sputtering technology;

Step 6: Depositing the second DLC layer, the preparation conditions are the same as step 4 to prepare the first DLC layer;

Step 7: Repeat step 5 three times and step 6 twice;

Step 8: Introduce high-purity acetylene with a flow rate of 38sccm, turn on the linear ion source and pulse bias, set the linear ion source current and pulse bias to 0.2A and -150V respectively, and use linear ion source technology in TiC _x /Ti/ Deposit on the TiC _x layer for 24min to prepare the third DLC top layer;

As shown in the cross-sectional SEM photo of Figure 2, the prepared coating has an alternating multilayer structure of TiC _x /Ti/TiC _x layers and DLC layers. The coating is dense and complete without obvious defects, and is tightly bonded to the stainless steel substrate. The total thickness of the coating is is 1.57 μm. As shown in Figure 3, the 63-day room temperature immersion test in 3.5wt% NaCl solution showed that the polarization resistance (R _p ) of the prepared coating remained at 3.0×10 ⁷ Ω·cm ² after immersion, higher than An order of magnitude more than the 316L stainless steel substrate, exhibiting excellent long-term corrosion protection against 316L stainless steel. As shown in Figure 4, when the linear reciprocating friction and wear test (stroke 5mm, frequency 2Hz) was carried out with Φ6mm Al ₂ O ₃ ceramic balls under the load of 5N in 3.5wt% NaCl solution, the coating was prepared in a time length of 36.5h ( During the test with a sliding distance of 2628m), the coefficient of friction was always maintained at <0.10, and the surface of the coating was only slightly damaged by abrasion, showing the long-life abrasion protection performance of 316L stainless steel in a seawater environment.

Example 2:

In this example, the base material is UNS S32750 (SAF 2507) super duplex stainless steel, and the coating is a multilayer structure in which TiC _x /Ti/TiC _x layers and DLC layers are periodically stacked alternately, wherein the surface of S32750 is a Ti transition layer, The total coating thickness is 2.3 μm.

The coating preparation steps on the surface of the above S32750 are as follows:

Step 1: Use 120#~3000# SiC metallographic sandpaper to polish the S32750 substrate in turn, and then use Al ₂ O ₃ abrasive paste with a particle size of 0.2~0.3μm to metallographically polish the substrate for 12 minutes;

Step 2: Place the polished S32750 substrate in acetone, ethanol and deionized water in sequence for ultrasonic cleaning for 10 minutes, and then dry it with cold air for later use;

Step 3: Place the S32750 substrate in the vacuum chamber for film deposition, use the mechanical pump and the turbomolecular pump to evacuate to 2.0×10 ^-5 Torr, turn on the heater and set the heating temperature to 150°C, and turn on the vacuum after the temperature reaches Introduce high-purity argon gas with a flow rate of 30 sccm into the chamber, turn on the linear ion source and pulse bias voltage, set the linear ion source current and pulse bias voltage to 0.2A and -200V respectively, and perform bias etching cleaning on the S32750 substrate for 45 minutes;

Step 4: feed high-purity argon gas of 48sccm flow rate and high-purity acetylene of 4.8sccm flow rate (acetylene is only passed through when depositing TiC _x layer), open DC magnetron sputtering source and pulse bias, set DC magnetron respectively Controlled sputtering source current and pulse bias are 3.0A and -150V, using DC magnetron sputtering technology to sputter on the substrate surface for 10min+10min to prepare Ti transition layer and TiC _x gradient layer; , turn on the linear ion source and pulse bias voltage, set the linear ion source current and pulse bias voltage to 0.2A and -150V respectively, and use linear ion source technology to deposit 18min on the TiC _x gradient layer to prepare the first DLC layer;

Step 5: feed high-purity argon of 48sccm flow and high-purity acetylene of 4.8sccm flow (acetylene is only passed through when depositing TiC _x layer), open the DC magnetron sputtering source and pulse bias, and set the DC magnetron respectively The sputtering source current and pulse bias are 3.0A and -150V, and the TiC _x /Ti/TiC _x layer is prepared by sputtering on the DLC layer for 9min+9min+9min by DC magnetron sputtering technology;

Step 6: Depositing the second DLC layer, the preparation conditions are the same as step 4 to prepare the first DLC layer;

Step 7: Repeat step 5 three times and step 6 twice;

Step 8: Introduce high-purity acetylene with a flow rate of 38sccm, turn on the linear ion source and pulse bias, set the linear ion source current and pulse bias to 0.2A and -150V respectively, and use linear ion source technology in TiC _x /Ti/ Deposit on the TiC _x layer for 36min to prepare a thickened third DLC top layer;

The electrochemical impedance spectroscopy and potentiodynamic polarization curve test results in 3.5wt% NaCl showed that the polarization resistance and self-corrosion current density of the prepared coating were 7.2×10 ⁷ Ω·cm ² and 3.5×10 ^-10 A ·cm ^-2 , significantly improved the electrochemical corrosion resistance of the S32750 substrate. When a linear reciprocating friction and wear test is carried out with a Φ6mm Al ₂ O ₃ ceramic ball under a 5N load in a 3.5wt% NaCl solution (stroke 5mm, frequency 2Hz), the test process of the prepared coating lasts 12h (sliding distance 864m) The friction coefficient is always kept < 0.08, and only shallow polishing wear marks appear on the surface of the coating (Figure 5), showing excellent abrasion protection performance for S32750SS in seawater environment. In addition, as shown in Figure 6, in the abrasion test under a 20N load for 12 hours, although the prepared coating has been worn through (the maximum depth of the wear scar is greater than the overall thickness of the coating), the friction coefficient still remains at Below 0.15 (significantly lower than 0.31 of the S32750 substrate), that is, the coating still maintains a certain anti-friction lubrication effect, showing good failure tolerance, which is of great significance for avoiding catastrophic coating abrasion failure.

Example 3

In this example, the base material is UNS S32750 super duplex stainless steel, and the coating is a multilayer structure in which TiC _x /Ti/TiC _x layers and DLC layers are periodically laminated, wherein the surface of S32750 is a Ti metal transition layer, and the total coating is The thickness is 2.8 μm.

The coating preparation steps on the surface of the above S32750 are as follows:

Step 1: same as Step 1 in Example 2;

Step 2: same as step 2 in Example 2;

Step 3: Place the S32750 substrate in the vacuum chamber for film deposition, use the mechanical pump and the turbomolecular pump to evacuate to 2.0×10 ^-5 Torr successively, then turn on the heater and set the heating temperature to 120°C, and turn on the vacuum after the temperature reaches Introduce high-purity argon gas with a flow rate of 36 sccm into the chamber, turn on the linear ion source and pulse bias voltage, set the linear ion source current and pulse bias voltage to 0.25A and -250V respectively, and perform bias etching cleaning on the S32750 substrate for 35 minutes;

Step 4: Feed high-purity argon gas with a flow rate of 50 sccm and high-purity acetylene with a flow rate of 5 sccm (acetylene is only fed in when the TiC _x layer is deposited), turn on the DC magnetron sputtering source and pulse bias, and set the DC magnetron respectively The sputtering source current and pulse bias are 3.0A and -200V, and the Ti transition layer and TiC _x gradient layer are prepared by sputtering on the surface of the substrate by DC magnetron sputtering technology for 9 min + 9 min; then, high-purity acetylene with a flow rate of 36 sccm is introduced , turn on the linear ion source and pulse bias voltage, set the linear ion source current and pulse bias voltage to 0.2A and -200 V respectively, and use the linear ion source technology to deposit 12min on the TiC _x gradient layer to prepare the first DLC layer;

Step 5: feed high-purity argon gas with a flow rate of 50 sccm and high-purity acetylene with a flow rate of 5 sccm (acetylene is only fed in when the TiC _x layer is deposited), turn on the DC magnetron sputtering source and pulse bias, and set the DC magnetron The sputtering source current and pulse bias are 3.0A and -200V, and the TiC _x /Ti/TiC _x layer is prepared by sputtering on the DLC layer for 6 min+6min+6min using DC magnetron sputtering technology;

Step 6: Depositing the second DLC layer, the preparation conditions are the same as step 4 to prepare the first DLC layer;

Step 7: Repeat step 5 five times and step 6 four times;

Step 8: Introduce high-purity acetylene with a flow rate of 36 sccm, turn on the linear ion source and pulse bias voltage, set the linear ion source current and pulse bias voltage to 0.2A and -200V respectively, and use linear ion source technology in TiC _x /Ti/ The third DLC top layer was prepared by depositing on the TiC _x layer for 24 minutes.

The electrochemical test results in 3.5wt% NaCl solution show that the electrochemical corrosion resistance of the prepared coating is equivalent to that of the coating in Example 2, and also shows good corrosion protection ability to the S32750 substrate. In the abrasion test of 3.5wt% NaCl solution under 5N load for 24h, the coating always maintains good anti-friction and lubrication performance, only local abrasion damage marks appear on the surface, and the coating remains intact; under 20N load for 12h In the abrasion test, the coating maintains good anti-friction and lubricating effect within a certain period of time as the coating in Example 2 after wear-through, showing good abrasion failure tolerance.

Comparative Example 1

This example is a comparative example of Example 2.

In this embodiment, the substrate is S32750 super duplex stainless steel. The coating is a multilayer structure in which Ti layers and DLC layers are stacked alternately periodically, in which the surface of S32750 is a Ti metal transition layer, and the total thickness of the coating is 2.3 μm.

The coating preparation steps on the surface of the above S32750 are as follows:

Step 1: same as Step 1 in Example 2;

Step 2: same as step 2 in Example 2;

Step 3: same as step 3 in Example 2;

Step 4: Introduce high-purity argon gas with a flow rate of 48sccm, turn on the DC magnetron sputtering source and pulse bias voltage, set the DC magnetron sputtering source current and pulse bias voltage to 3.0A and -150V respectively, and use DC magnetron sputtering The Ti layer was prepared by sputtering technology on the surface of the substrate for 20 minutes;

Step 5: Introduce high-purity acetylene with a flow rate of 38sccm, turn on the linear ion source and pulse bias, set the linear ion source current and pulse bias to 0.2A and -150V respectively, and use the linear ion source technology to deposit on the Ti layer for 18min Prepare DLC layer;

Step 6: Introduce high-purity argon gas with a flow rate of 48sccm, turn on the DC magnetron sputtering source and pulse bias voltage, set the DC magnetron sputtering source current and pulse bias voltage to 3.0A and -150V respectively, and use DC magnetron sputtering The Ti layer was prepared by sputtering on the surface of the substrate for 27 minutes;

Step 7: Repeat Step 5 and Step 6 three times;

Step 8: Introduce high-purity acetylene with a flow rate of 38sccm, turn on the linear ion source and pulse bias, set the linear ion source current and pulse bias to 0.2A and -150V respectively, and use the linear ion source technology to deposit on the Ti layer for 36min Prepare a thickened DLC top layer.

The nanoindentation test results show that the nanohardness of the prepared coating is 7.2GPa, and the elastic modulus is 129.6 GPa, which are significantly lower than the _TiCx /Ti/ _TiCx /DLC multilayer coating prepared in Example 2; at 3.5 In the abrasion test of wt% NaCl solution under 5N load for 12 hours, although the prepared coating always maintains good anti-friction and lubrication performance (COF<0.08), the surface has obvious plastic deformation and chipping and peeling, as shown in Figure 7 shown.

Comparative Example 2

This example is a comparative example of Example 2.

In this embodiment, the substrate is S32750 super duplex stainless steel. The coating is a multi-layer structure in which TiC _x layers and DLC layers are periodically stacked alternately. The surface of S32750 is a TiC _x transition layer, and the top of the coating is a thickened DLC anti-friction and wear-resistant layer. The total thickness of the coating is 2.3 μm.

The coating preparation steps on the surface of the above S32750 are as follows:

Step 1: same as Step 1 in Example 2;

Step 2: same as step 2 in Example 2;

Step 3: same as step 3 in Example 2;

Step 4: Introduce high-purity argon gas with a flow rate of 48sccm and high-purity acetylene with a flow rate of 4.8sccm, turn on the DC magnetron sputtering source and pulse bias voltage, and set the DC magnetron sputtering source current and pulse bias voltage to 3.0A respectively and -150V, using DC magnetron sputtering technology to sputter on the surface of the substrate for 20min to prepare the TiC _x layer;

Step 5: Introduce high-purity acetylene with a flow rate of 38sccm, turn on the linear ion source and pulse bias, set the linear ion source current and pulse bias to 0.2A and -150V, respectively, and use the linear ion source technology to deposit on the TiC _x layer 18min to prepare the DLC layer;

Step 6: Introduce high-purity argon gas with a flow rate of 48sccm and high-purity acetylene with a flow rate of 4.8sccm, turn on the DC magnetron sputtering source and pulse bias voltage, and set the DC magnetron sputtering source current and pulse bias voltage to 3.0A respectively and -150V, using DC magnetron sputtering technology to sputter on the surface of the substrate for 27min to prepare the TiC _x layer;

Step 7: Repeat Step 5 and Step 6 three times;

Step 8: Introduce high-purity acetylene with a flow rate of 38 sccm, turn on the linear ion source and pulse bias, set the linear ion source current and pulse bias to 0.2A and -150V respectively, and use linear ion source technology to deposit on the TiC _x layer 36 min to prepare a thickened DLC top layer.

The nano-indentation test results show that the nano-hardness of the prepared coating is 15.3GPa, and the elastic modulus is 151.1 GPa, which is slightly higher than that of the coating prepared in Example 2; the scratch test results show that the combination of the prepared coating and S32750 The strength is 4.8N, which is obviously lower than that of the coating prepared in Example 2; in addition, the fracture toughness (K _IC ) results of the micro-Vickers indentation method show that the K _IC of the prepared coating is 1.22MPa·m ^{1 /2} , which is lower than that of the multilayer coating prepared in Example 2; in the abrasion test of 12 hours under 5N load in 3.5wt% NaCl solution, the prepared coating is the same as that of Comparative Example 1, although it always maintains good wear resistance friction and lubrication properties (COF<0.08), but the surface also showed obvious signs of chipping and peeling, as shown in Figure 8.

In addition, the inventor of the present case also carried out tests with other raw materials and conditions listed in this description with reference to the mode of Examples 1-3, and obtained the same result.

It should be understood that the above-mentioned embodiments are only to illustrate the technical conception and characteristics of the present invention, and its purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention shall fall within the protection scope of the present invention.

Claims (10)

1. a kind of metal base surface anti scuffing protective coating, it is characterised in that including the Ti sequentially formed in metal base surface Transition zone, TiC_xGradient layer, the first DLC layer, TiC_x/Ti/TiC_x/ DLC stacked layers and top layer, wherein the TiC_x/Ti/ TiC_x/ DLC stacked layers are by TiC_x/Ti/TiC_xSandwich layer and the alternately laminated formation of the second DLC layer, the TiC_x/Ti/ TiC_xSandwich layer includes two TiC_xLayer and be set to described two TiC_xOne Ti layer between layer, the top layer includes the Three DLC layers, the TiC_xThe value range of middle X is 0.8~1.3.

2. anti scuffing protective coating according to claim 1, which is characterized in that the TiC_x/Ti/TiC_x/ DLC alternating layer Lamination includes 4~7 alternately laminated period layers, wherein each alternately laminated period layer includes a TiC_x/Ti/TiC_xSandwich Layer and a DLC layer.

3. anti scuffing protective coating according to claim 1, which is characterized in that the anti scuffing protective coating with a thickness of 1.5~2.8 μm；

And/or the Ti transition zone, TiC_xGradient layer, the first DLC layer, TiC_x/Ti/TiC_x/ DLC, the second DLC layer, the 3rd DLC The thickness ratio of layer is 1:(1~1.2): (0.8~1.2): (1.6~2.4): (0.8~1.2): (2.0~3.0)；

And/or the third DLC layer with a thickness of 200~300nm.

4. anti scuffing protective coating according to claim 1, which is characterized in that the metallic matrix includes stainless base steel Body；Preferably, the metallic matrix includes 316L stainless steel and/or S32750 stainless steel.

5. the preparation method of anti scuffing protective coating described in any one of claim 1-4, characterized by comprising:

S1. metal base surface is pre-processed；

S2. Ti transition zone, TiC are sequentially depositing in metal base surface using magnetically controlled DC sputtering technology_xGradient layer, then use line Property technology of ion source is in TiC_xGradient layer surface deposits the first DLC layer；

S3. using magnetically controlled DC sputtering technology in the first DLC layer surface depositing Ti C_x/Ti/TiC_xSandwich layer, and using linear Technology of ion source deposits the second DLC layer, and makes the TiC_x/Ti/TiC_xSandwich layer and the second DLC layer are alternately laminated, are formed TiC_x/Ti/TiC_x/ DLC alternating layer；

S4. using linear ion source technology in TiC_x/Ti/TiC_xThird DLC layer is deposited on/DLC alternating layer, is formed described wear-resistant Lose protective coating.

6. the preparation method of anti scuffing protective coating according to claim 5, which is characterized in that step S1 is specifically included:

It is successively polished metallic matrix using the SiC abrasive paper for metallograph of 120#~3000#, reuses 0.2~0.3 μm of partial size Al₂O₃Abrasive pastes are processed by shot blasting 10~15min to metallic matrix；

Metallic matrix after polishing is successively subjected to 5~15min of ultrasonic cleaning, cold wind drying with acetone, ethyl alcohol, deionized water；

Metallic matrix is placed in film deposition vacuum room, is evacuated to 2.0 × 10^-5Torr, make later chamber heating 120~ 150 DEG C, it then is passed through the argon gas that gas flow is 30~36sccm to vacuum chamber, opens linear ion source and pulsed bias pair Matrix carries out bias 30~45min of etch cleaner, and wherein linear ion ource electric current and pulsed bias are respectively 0.20~0.25A With -200~-250V.

7. the preparation method of anti scuffing protective coating according to claim 5, which is characterized in that depositing Ti mistake in step S2 The condition for crossing layer includes: Ti target, 48~52sccm of argon flow, acetylene flow 0sccm, 9~10min of sedimentation time, DC magnetic Control sputtering ource electric current and pulsed bias are respectively 3.0A and -150~-200V；Depositing Ti C_xThe condition of gradient layer includes: Ti target, 48~52sccm of argon flow, acetylene 4.8~5.2sccm of flow, 9~10min of sedimentation time, magnetically controlled DC sputtering ource electric current and Pulsed bias is respectively 3.0A and -150~-200V；The condition for depositing the first DLC layer includes: acetylene 36~40sccm of flow, is sunk Product 12~18min of time, linear ion ource electric current and pulsed bias are respectively 0.2A and -150~-200V.

8. the preparation method of anti scuffing protective coating according to claim 5, which is characterized in that depositing Ti C in step S3_x/ Ti/TiC_xTiC in sandwich layer_xThe condition of layer includes: Ti target, 48~52sccm of argon flow, and acetylene flow 4.8~ 5.2sccm, 6~9min of sedimentation time, magnetically controlled DC sputtering ource electric current and pulsed bias are respectively 3.0A and -150~-200V； Depositing Ti C_x/Ti/TiC_xTi layers of condition includes: Ti target, 48~52sccm of argon flow, acetylene flow in sandwich layer 0sccm, 6~9min of sedimentation time, magnetically controlled DC sputtering ource electric current and pulsed bias are respectively 3.0A and -150~-200V；It is heavy The condition of the second DLC layer of product includes: acetylene 36~40sccm of flow, 12~18min of sedimentation time, linear ion ource electric current and arteries and veins Rushing bias is respectively 0.2A and -150~-200V.

9. the preparation method of anti scuffing protective coating according to claim 5, which is characterized in that deposit third in step S4 The condition of DLC layer includes: acetylene 36~40sccm of flow, 24~36min of sedimentation time, linear ion ource electric current and pulsed bias Respectively 0.2A and -150~-200V.

10. metal base surface anti scuffing protective coating of any of claims 1-4 is in sea water pump moving component table Purposes in the protection field of face.