CN117364043B

CN117364043B - Aluminum alloy PVD fluidization process

Info

Publication number: CN117364043B
Application number: CN202311363399.5A
Authority: CN
Inventors: 文晓斌
Original assignee: Shenzhen Kingmag Precision Technology Co ltd
Current assignee: Shenzhen Kingmag Precision Technology Co ltd
Priority date: 2023-10-20
Filing date: 2023-10-20
Publication date: 2024-09-03
Anticipated expiration: 2043-10-20
Also published as: CN117364043A

Abstract

The invention relates to the technical field of material surface modification, in particular to an aluminum alloy PVD fluidization process. The method is characterized in that: and (3) pumping the gas in the vacuum sputtering chamber to ensure that the pressure difference between the upper guide opening and the lower guide opening is 350Pa, guiding the gas in the vacuum sputtering chamber to spirally flow along the spiral blade hanging frame from bottom to top, controlling the gas flow rate to be 300-500ml/s, forming gas phase particles formed by target atoms into fluidized steam to flow through the surface of the aluminum alloy substrate workpiece, ensuring that the surface of the aluminum alloy substrate workpiece obtains uniform film deposition, exchanging the pressure difference between the upper guide opening and the lower guide opening, guiding the gas in the vacuum sputtering chamber to spirally flow along the spiral blade hanging frame from top to bottom, circularly reciprocating in such a way, ensuring that the film deposition time is 4-8 h, and keeping the temperature in the vacuum sputtering chamber within the range of 100 ℃ to obtain the multilayer coating.

Description

Aluminum alloy PVD fluidization process

Technical Field

The invention relates to the technical field of material surface modification, in particular to an aluminum alloy PVD fluidization process.

Background

Physical Vapor Deposition (PVD) is used as a material surface coating technology, and the film has the characteristics of high hardness, high wear resistance, low friction coefficient, good corrosion resistance, chemical stability and the like, and has longer service life, and meanwhile, the film can greatly improve the appearance decoration performance of a workpiece. The PVD main coating base material has two major types of stainless steel and titanium alloy, the two coating base materials have high surface hardness, high temperature resistance and strong oxidation resistance, and have good binding force with PVD target material components, if the aluminum alloy is used as the coating base material, the surface hardness is lower, the high temperature resistance is poorer, the surface oxidation resistance is poorer, the PVD coating binding force is poorer, but the processing and manufacturing cost of the aluminum alloy material is lower, and the PVD coating base material is particularly suitable for processing products with complex surfaces and holes. Chinese patent application No. CN201480016804.9 (patent name PVD apparatus and PVD method) discloses a PVD apparatus and a PVD method for forming a film on the surfaces of a plurality of substrates, comprising: a vacuum chamber for accommodating the plurality of substrates; a revolution table provided in the vacuum chamber and configured to revolve the plurality of substrates around a revolution axis while supporting the substrates; a plurality of rotating tables each of which rotates one of the plurality of substrates on the revolution table about a rotation axis parallel to the revolution axis while supporting the substrate; a plurality of targets formed of different types of film forming materials, and disposed at a plurality of positions separated from each other in the circumferential direction on the outer side of the revolution table in the radial direction; and a stage rotation mechanism that rotates each of the spin stages around the rotation shaft in accordance with rotation of the revolution stage, wherein the stage rotation mechanism rotates the spin stage on which the substrate is mounted at an angle of 180 ° or more with respect to the revolution stage while the substrate passes between two tangential lines drawn from respective centers of the plurality of targets to an arc enveloping each of the spin stages, and rotates the rotation direction of the revolution stage and the rotation direction of all the spin stages in the same direction.

There are many Physical Vapor Deposition (PVD) technical routes, but they are all methods for preparing a film layer by evaporating or sputtering a film coating material in a vacuum state, and the film coating material is deposited on a substrate, so that the physical vapor deposition needs to undergo three links: the plating material (target material) is gasified, transported in gas phase and deposited into a film. Gasifying plating materials (targets): atoms on the surface of the target absorb energy and are activated to a certain energy level, the bonding attraction of the atoms in the target is eliminated, the target is in a gas phase state, the heating mode of the target is called evaporation, and the process of bombarding atoms (molecules) or atomic groups from the surface of the target by inert gas ions is called sputtering; gas phase transport: in the vacuum condition, the bombarded atoms form an electric neutral particle flow, and the electric neutral particle flow diffuses from a target material area with higher concentration to a substrate area with lower concentration, and because the concentrations of gas phase particles and residual inert gas are low enough, the particles keep straight line flight from a target source to a substrate, and the particles can not collide with residual molecules and scatter in the transportation process, so that the technical problems are generated, namely, the gas phase particles of a coating material can only move straight line and can only be deposited on the front surface of the substrate, and the back and the side surfaces of the coating material can not be deposited, therefore, a revolution table and a plurality of self-rotation tables are designed in a vacuum chamber in the prior art, so that the surface of the substrate receives the projection of the fixed target material particles in a revolution and self-rotation mode of a mechanism, but the difficulty of film forming of the substrate with a complex surface and holes is high, and the technical problems of vacuum sealing and insulation brought by the complex mechanism are difficult to solve; and (3) deposition film forming: the substrate adsorbs vapor phase particles of a coating material in a physical adsorption and chemical adsorption mode, the vapor phase particles are converted into a stable state from an excited state in a bonding mode with atoms on the surface of the substrate, adsorption heat is released in the process of condensing the vapor phase into a solid phase, crystal nuclei appear and grow to form a film, the pressure of residual inert gas is too high, the collision probability between the vapor phase particles and the molecules of the residual inert gas can be increased, the deposition rate can be influenced, vapor pressure generated by sputtering is continuously increased, and the problems that the aluminum alloy coating substrate is poor in high temperature resistance, poor in surface oxidation resistance, poor in PVD film binding force and easy to deform are more remarkable due to the increase of the pressure of a container and the release of adsorption heat. The above-mentioned prior art "PVD processing apparatus and PVD processing method" does not propose a targeted solution.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide an aluminum alloy PVD fluidization process, which is characterized in that: step one, an upper end cover is opened, a spiral diversion workbench is lifted out of a vacuum sputtering chamber, the spiral diversion workbench is provided with a supporting frame and a spiral blade hanging frame, the spiral blade hanging frame is fixed in the upper end cover through the supporting frame, the axial lead of the spiral blade hanging frame is coaxial with the central line of the vacuum sputtering chamber, a pre-cleaned aluminum alloy substrate workpiece is placed on the spiral blade hanging frame, the spiral diversion workbench is placed in the vacuum sputtering chamber, the upper end cover is folded and sealed with the vacuum sputtering chamber, and a vacuum system is started after leakage detection.

Secondly, introducing inert gas argon after the vacuum degree in the vacuum sputtering chamber reaches 0.1-1.0 Pa, controlling the flow to be 50-200ml/s, igniting and discharging a plasma discharger when the vacuum degree in the vacuum sputtering chamber reaches 266-399 Pa, enabling negative bias voltage of a cathode target to be 600V, enabling electrons released by the plasma discharger to accelerate to fly away from the cathode target under the action of an electric field, enabling electrons to collide with argon atoms and ionize to obtain argon positive ions, enabling the argon positive ions to accelerate under the action of the electric field, flying towards the cathode target, bombarding the surface of the target, enabling the target to generate sputtering, enabling the cathode target to be uniformly distributed along the wall of the vacuum sputtering chamber in a ring shape, enabling gas phase particles formed by sputtered neutral target atoms to flow to each surface of a base material and be projected, the annular permanent magnet is arranged behind the cathode target, so that an electric field and a magnetic field are in an orthogonal state, arc-shaped closed magnetic lines are formed on the surface of the target, secondary electrons are sputtered from the surface of the target, the secondary electrons are restrained by Lorentz force of the magnetic field in the area near the target, and the secondary electrons are subjected to rotary motion around the magnetic lines near the surface of the target, so that the stroke of the secondary electrons is greatly increased, the collision probability with argon atoms is greatly increased, a sufficient number of argon positive ions are provided for continuously bombarding the cathode target, the formed plasma is subjected to glow discharge continuously, the temperature in a vacuum sputtering chamber is controlled within the range of 100 ℃, and the aluminum alloy substrate workpiece is subjected to glow cleaning for 10-15 min.

Step three: according to the coating design requirement, working gas nitrogen and hydrogen can be injected into a vacuum sputtering chamber through a process gas pipe orifice, the vacuum degree in the vacuum sputtering chamber is regulated to 399-532Pa, the negative bias voltage of a cathode target is 50-150V, the collision probability between gas molecules and gas particles formed by neutral target atoms sputtered from the target is greatly increased due to the pressure increase of inert gas and working gas, the gas in the vacuum sputtering chamber is not in a linear motion state and becomes a scattering state, a vacuum system is started at the moment to pump the gas in the vacuum sputtering chamber, the pressure difference between an upper diversion port and a lower diversion port is 350Pa, the gas in the vacuum sputtering chamber is led to flow spirally along a spiral blade hanging frame from bottom to top, the gas flow speed is controlled to 300-500ml/s, the gas particles formed by the target atoms form fluidized vapor through-flow aluminum alloy substrate workpiece surfaces, the uniform film deposition is obtained on the aluminum alloy substrate workpiece surfaces, the gas in the vacuum sputtering chamber is led to flow spirally along the spiral blade hanging frame from top to bottom, the circulating reciprocating time is 4-8 h, and the temperature in the vacuum sputtering chamber is kept within the range of 100 ℃ so that multilayer coating can be obtained.

Compared with the prior art, the invention has at least the following advantages: firstly, a magnetron sputtering technology suitable for aluminum alloy substrates is developed, gas in a vacuum sputtering chamber is led to flow along a spiral blade hanger in a spiral way, gas phase particles formed by target atoms form fluidized steam through-flow aluminum alloy substrate workpiece surfaces, so that uniform film deposition is obtained on the aluminum alloy substrate workpiece surfaces, a complex revolution table and a plurality of self-revolving table mechanisms are not required to be designed, the technical problem of film formation of the substrates with complex surfaces and holes is solved, and the technical problems of vacuum sealing and insulation brought by the revolution table and the plurality of self-revolving table mechanisms are not required to be considered; and secondly, the vacuum system is used for pumping out the gas of the vacuum sputtering chamber, the vapor pressure of the indoor target material is controlled, namely the temperature of the aluminum alloy substrate is controlled, and the problems of deformation, poor oxidation resistance and poor film bonding force of the substrate caused by temperature rise are solved.

Drawings

FIG. 1 is a schematic diagram of a PVD fluidization process for aluminum alloys in accordance with the present invention.

FIG. 2 is a schematic A-A cross-sectional view of an aluminum alloy PVD fluidization process according to the invention.

FIG. 3 is a schematic diagram of a B-bulk structure of an aluminum alloy PVD fluidization process of the present invention.

1-Upper diversion port 2-upper end cover 3-vacuum sputtering chamber 4-spiral diversion workbench

5-Lower end cover 6-lower diversion opening 7-support frame 8-helical blade hanging frame

9-Process gas nozzle 10-cathode target 11-Ring permanent magnet

12-Plasma discharger.

Detailed Description

The invention will be further described with reference to the drawings and the specific embodiments.

As shown in fig. 1,2 and 3, an aluminum alloy PVD fluidization process is characterized in that: step one, an upper end cover is opened, a spiral diversion workbench 4 is lifted out of a vacuum sputtering chamber 3, the spiral diversion workbench 4 is provided with a supporting frame 7 and a spiral blade hanging frame 8, the spiral blade hanging frame 8 is fixed in the upper end cover 2 through the supporting frame 7, the axial lead of the spiral blade hanging frame 8 is coaxial with the central line of the vacuum sputtering chamber 3, a pre-cleaned aluminum alloy substrate workpiece is placed on the spiral blade hanging frame 8, the spiral diversion workbench 4 is placed in the vacuum sputtering chamber 3, the upper end cover 2 is folded and sealed with the vacuum sputtering chamber 3, and a vacuum system is started after leakage detection.

Secondly, introducing inert gas argon after the vacuum degree in the vacuum sputtering chamber 3 reaches 0.1-1.0 Pa, controlling the flow to be 50-200ml/s, igniting and discharging the plasma discharger 12 when the vacuum degree in the vacuum sputtering chamber 3 reaches 266-399 Pa, wherein the negative bias voltage of the cathode target 10 is 600V, electrons released by the plasma discharger 12 accelerate to fly away from the cathode target 10 under the action of an electric field, collide with argon atoms to ionize argon positive ions, the argon positive ions are accelerated under the action of the electric field, fly towards the cathode target 10, bombard the surface of the target, sputter the target, the cathode target 10 circularly uniformly distribute gas phase particles formed by sputtered neutral target atoms along the wall of the vacuum sputtering chamber 3 flow to each surface of an aluminum alloy substrate, and installing an annular permanent magnet 11 after the cathode target 10, so that the electric field and the magnetic field are in an orthogonal state, then arc-shaped closed state is formed on the surface of the target, therefore, secondary electrons are sputtered off from the surface of the target, are constrained by the lorentz force of a magnetic field in a region near the target, and surround the surface of the target to make a whirling motion around the argon atoms, so that the argon atoms are greatly increased, the probability of collision with the vacuum sputtering target 10 is greatly increased, the number of the atoms is continuously controlled within a range of 100 min, and the vacuum sputtering chamber is continuously controlled within a range of the vacuum sputtering chamber is kept in a range of 100 min, and the vacuum sputtering chamber is continuously formed to the vacuum sputtering target is continuously cleaned.

Step three: according to the coating design requirement, working gas nitrogen and hydrogen can be injected into the vacuum sputtering chamber 3 through the process gas pipe orifice 9, the vacuum degree in the vacuum sputtering chamber 3 is regulated to 399-532Pa, the negative bias voltage of the cathode target 10 is 50-150V, the collision probability between gas molecules and gas particles formed by neutral target atoms sputtered from the target is greatly increased due to the pressure increase of inert gas and working gas, the gas in the vacuum sputtering chamber 3 is not in a linear motion state and becomes a scattering state, at the moment, a vacuum system is started to pump the gas in the vacuum sputtering chamber 3, so that the pressure difference between the upper diversion port 1 and the lower diversion port 6 is 350Pa, the gas in the vacuum sputtering chamber 3 is led to flow spirally along the spiral blade hanging frame 8 from bottom to top, the gas flow rate is controlled to 300-500ml/s, the gas phase particles formed by the target atoms form fluidized vapor through-flow aluminum alloy substrate workpiece surface, the uniform film deposition is obtained on the aluminum alloy substrate workpiece surface, the gas in the vacuum sputtering chamber 3 is led to flow spirally along the spiral blade hanging frame 8 from top to bottom, the circulating reciprocating mode is carried out, the film deposition time is 4-8 h, and the temperature of the vacuum sputtering chamber is kept within the range of 100 ℃ to obtain the multilayer coating.

Claims

1. An aluminum alloy PVD fluidization process is characterized in that: comprises the following steps

Opening an upper end cover, hanging a spiral diversion workbench out of a vacuum sputtering chamber, placing a pre-cleaned aluminum alloy substrate workpiece on a spiral blade hanging frame, placing the spiral diversion workbench into the vacuum sputtering chamber, closing the upper end cover and the vacuum sputtering chamber, sealing, and starting a vacuum system after detecting leakage;

Secondly, introducing inert gas argon after the vacuum degree in the vacuum sputtering chamber reaches 0.1-1.0 Pa, controlling the flow to be 50-200ml/s, igniting and discharging a plasma discharger when the vacuum degree in the vacuum sputtering chamber reaches 266-399 Pa, wherein the negative bias voltage of the cathode target is 600V, electrons released by the plasma discharger are accelerated to fly away from the cathode target under the action of an electric field and collide with argon atoms to ionize argon positive ions, the argon positive ions are accelerated under the action of the electric field, fly towards the cathode target and bombard the surface of the target, sputtering is generated on the target, a ring-shaped permanent magnet is arranged behind the cathode target, so that the electric field and the magnetic field are in an orthogonal state, arc-shaped closed magnetic lines are formed on the surface of the target, secondary electrons are sputtered on the surface of the target, the secondary electrons are restrained by the Lorentz force of the magnetic field in the area near the target, the circular magnetic lines are revolved around the surface of the target, the travel of the secondary electrons is greatly increased, the collision probability with argon atoms is greatly increased, a sufficient quantity of positive ions is provided, the argon positive ions continuously bombard the cathode target, the formed plasma is continuously, the glow is continuously bombarded, and the vacuum glow of the target is controlled within the temperature range of 100 ℃ for cleaning a workpiece in a continuous time of 10 min, and the temperature range is kept for cleaning a substrate of the aluminum alloy in a vacuum state in a temperature range of 100 ℃ for 10 min;

Step three: according to the coating design requirement, working gas nitrogen and hydrogen can be injected into a vacuum sputtering chamber through a process gas pipe orifice, the vacuum degree in the vacuum sputtering chamber is regulated to 399-532Pa, the negative bias voltage of a cathode target is 50-150V, the collision probability between gas phase particles formed by neutral target atoms sputtered from the target and gas molecules is greatly increased due to the increase of the pressure of inert gas and the working gas, the gas phase particles are not in a linear motion state but are changed into a scattering state, the film deposition time is 4-8 h, and the temperature in the vacuum sputtering chamber is kept within the range of 100 ℃, so that the multilayer coating can be obtained.

2. An aluminum alloy PVD fluidization process according to claim 1, wherein: the spiral guide workbench is provided with a support frame and a spiral blade hanging frame, the spiral blade hanging frame is fixed in the upper end cover through the support frame, and the axial lead of the spiral blade hanging frame is coaxial with the central line of the vacuum sputtering chamber.

3. An aluminum alloy PVD fluidization process according to claim 1, wherein: the cathode targets are uniformly distributed along the annular shape of the vacuum sputtering chamber wall, and gas phase particles formed by sputtered neutral target atoms flow to each surface of the aluminum alloy substrate for projection.

4. An aluminum alloy PVD fluidization process according to claim 1, wherein: at the moment, a vacuum system is started to pump the gas of the vacuum sputtering chamber, so that the pressure difference between the upper diversion opening and the lower diversion opening is 350Pa, the gas in the vacuum sputtering chamber is guided to flow spirally along the spiral blade hanging frame from bottom to top, the gas flow speed is controlled to be 300-500ml/s, gas phase particles formed by target atoms form fluidized steam to flow through the surface of the aluminum alloy substrate workpiece, and uniform film deposition is obtained on the surface of the aluminum alloy substrate workpiece.

5. An aluminum alloy PVD fluidization process according to claim 1, wherein: exchanging the pressure difference between the upper guide opening and the lower guide opening, and guiding the gas in the vacuum sputtering chamber to spirally flow along the spiral blade hanging frame from top to bottom, so that the gas is circularly and reciprocally moved.