CN109136918A - A kind of preparation method of composite coating - Google Patents
A kind of preparation method of composite coating Download PDFInfo
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- CN109136918A CN109136918A CN201811103048.XA CN201811103048A CN109136918A CN 109136918 A CN109136918 A CN 109136918A CN 201811103048 A CN201811103048 A CN 201811103048A CN 109136918 A CN109136918 A CN 109136918A
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- Prior art keywords
- stainless steel
- preparation
- steel base
- ceramal
- powder
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C24/00—Coating starting from inorganic powder
- C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
- C23C24/10—Coating starting from inorganic powder by application of heat or pressure and heat with intermediate formation of a liquid phase in the layer
- C23C24/103—Coating with metallic material, i.e. metals or metal alloys, optionally comprising hard particles, e.g. oxides, carbides or nitrides
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F1/00—Etching metallic material by chemical means
- C23F1/10—Etching compositions
- C23F1/14—Aqueous compositions
- C23F1/32—Alkaline compositions
- C23F1/40—Alkaline compositions for etching other metallic material
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
Abstract
The present invention relates to a kind of preparation methods of composite coating, pass through chemical treatment, acid processing and Laser Surface Treatment, improve stainless steel surface modified technique, for the optimal cladding layer composite material of stainless steel mating chemical composition and process parameters range, so that final finished is not only wear-resisting and excellent anti-corrosion performance, microstructure is fine and close, and process costs are controllable, and service performance is fully able to meet market application demand.
Description
Technical field
The present invention relates to the field of metal processing, in particular to a kind of preparation method of composite coating.
Background technique
With the continuous development of technology with the generation of emerging technology, the development of surface engineering technology is also increasingly intended to more
Sample and diversification also handle to Multiple techniques combined processing the processing of material surface from monotechnics and change.Meanwhile
The Technology design of the demand for development Surface Engineering of industry will be from the Experience Design stage to System Design stage development and breakthrough.To more
The demand of kind functional coating constantly expands, and new coating material continues to bring out, and all specifies for the development of Surface Engineering new
Direction.The research that deepens continuously of basic theory and test method to Surface Engineering, the technical field of extended surface engineering energetically,
The automation of raising surface engineering technology, intelligent level are the development trends of Modern Surface Engineering.
Currently, to be the absence of laser melting coating dedicated for the major reason that the popularization and application of laser melting and coating technique are restricted
Material system.The material system of present laser cladding is mainly or using spraying alloy powder system, with laser melting coating skill
Art is continuously improved in the requirement of process aspect, highly desirable to develop novel seriation laser cladding of material system, so as to reality
Existing resource is distributed rationally.Present many institution of higher learning and scientific research institutions both domestic and external all oneself warps are dedicated molten in laser melting and coating technique
It covers to expand correlation in terms of material and grind and make internal disorder or usurp.Li Ainong etc. uses laser cladding method, prepares iron-based-Cr in 45 steel surfaces3C2/
MoS2Wear resistant friction reducing coating, Cr3C2Decomposition has mainly generated Cr23C6Hard phase, MoS2It has partially decomposed forming CrS particle and has protected
The MoS stayed2Significantly improve the friction and wear behavior of coating.Jyotsna Duttamajumdar etc. is used in titanium alloy surface to be swashed
Light melting and coating technique cladding Ti+2%B, the TiB of generation2Dispersed precipitate in α-Ti matrix, the hardness and Young's modulus of coating all compared with
Matrix significantly increases.P.K.Farayibi etc. utilizes laser melting and coating technique cladding in the way of synchronous powder feeding system in titanium alloy surface
TC4- 73wt%WC, TiC, W in cladding layer2C, the presence of β-Ti, TiC and W improve the hardness number of coating.Cui Gang etc. is 45
Steel surface laser fusion covered nickel base WC alloy coat obtains mouldability when scanning speed is 200mm/min and wear resistance and corrosion resistance is excellent
Good cladding layer.
It is current in the prior art, to the laser melting coating process for modifying surface of stainless steel plate also in research and development initial stage, exist
Many product quality defects, for example, the surface fused coating of stainless steel finished product has the defects of apparent crackle, stomata, cladding layer
Interior tissue is not fine and close enough and surface flatness is difficult to meet the requirements.
Summary of the invention
In order to solve the above-mentioned technical problems, the present invention provides a kind of preparation method of composite coating, this method can
To improve the coating consistency of stainless steel product, the defects of reducing crackle, stomata, improves the wear-resisting property of stainless steel product and resistance to
Corrosive nature can satisfy stainless steel product using required performance.
A kind of preparation method of composite coating, comprising the following steps:
Firstly, stainless steel base is put into NaOH solution, it is rinsed with water after handling 2~10min at 40~50 DEG C, then
Stainless steel base after alkaline etching is put into nitric acid solution and impregnates 15-30s, takes out be rinsed with water again later；
Then, use preset method pre-set thickness for 0.1~1.0mm copper metal powder last layer on stainless steel base surface；
Then, use preset method pre-set thickness for 2~4mm ceramal mixed powder last layer on copper metal powder last layer surface,
To form coating material on stainless steel base surface, in the ceramal mixed-powder, alloying component include for Cu, Al,
Ti, W, ceramic composition Al2O3And SiO2Mixture；
Finally, the coating material to stainless steel base surface carries out laser melting coating, it is passed through helium atmosphere in the process, to make
Stainless steel base surface forms composite coating.
The stainless steel base uses super austenitic stainless steel N08367.
The mass ratio of alloying component and ceramic composition is (2~8) in the ceramal mixed-powder: 1.
The copper metal powder and ceramal mixed-powder are previously placed in baking oven and pretreatment are dried for 120 DEG C
2h。
The laser melting coating is carried out using optical fiber laser, the laser power of laser is 5kW~8kW, and scanning speed is
10~30mm/s.
Protective atmosphere is formed using the protection gas hood of helium atmosphere, carries out the laser melting coating step.
The partial size of the ceramal mixed-powder is 10-30nm.
Compared with prior art, the invention has the advantages that passing through the laser table under chemical treatment, acid processing and particular atmosphere
Surface treatment improves stainless steel surface modified technique, for the optimal cladding layer composite material of stainless steel mating chemical composition and technique
Parameter area, so that final stainless steel knife finished product, not only wear-resisting and excellent anti-corrosion performance, microstructure is fine and close, technique
Cost is controllable, and service performance is fully able to meet the application demand of cutter commodity.
Specific embodiment
Conventional alloys coated cutting tool is still used as cutting tool extensive use in stainless steel knife market, but cannot say
It is best.Because difficulty is bigger in cutter cutting experiment, the material of research is than relatively limited, so being found
Metal material in diamond cutter be the best cutter of generally acknowledged effect because it is not easy thermally conductive, rapid heat dissipation, and be not easy
It reacts with other chemical substances, but its price is that ordinary people can not accept.It is known that in the mistake of machining
Cheng Zhong, cutter and cutting product have very strong interaction force, this to be cut product or cutter need to have it is very strong wear-resisting
Damage property.
Below with reference to embodiment and comparative example, the present invention is described in more detail.
Embodiment 1:
A kind of preparation method of composite coating, comprising the following steps:
Firstly, stainless steel base is put into NaOH solution, it is rinsed with water after handling 10min at 40 DEG C, then by alkaline etching
Stainless steel base afterwards, which is put into nitric acid solution, impregnates 15s, takes out be rinsed with water again later；
Then, use preset method pre-set thickness for 1.0mm copper metal powder last layer on stainless steel base surface；
Then, use preset method pre-set thickness for 4mm ceramal mixed powder last layer on copper metal powder last layer surface, thus
Form coating material on stainless steel base surface, in the ceramal mixed-powder, alloying component include be Cu, Al, Ti, W,
Ceramic composition is Al2O3And SiO2Mixture；
Finally, the coating material to stainless steel base surface carries out laser melting coating, it is passed through helium atmosphere in the process, to make
Stainless steel base surface forms composite coating.
The stainless steel base uses super austenitic stainless steel N08367.
The mass ratio of alloying component and ceramic composition is 2:1 in the ceramal mixed-powder.
The copper metal powder and ceramal mixed-powder are previously placed in baking oven and pretreatment are dried for 120 DEG C
2h。
The laser melting coating is carried out using optical fiber laser, the laser power of laser is 8kW, scanning speed 10mm/
s。
Protective atmosphere is formed using the protection gas hood of helium atmosphere, carries out the laser melting coating step.
The partial size of the ceramal mixed-powder is 10nm.
Embodiment 2:
A kind of preparation method of composite coating, comprising the following steps:
Firstly, stainless steel base is put into NaOH solution, it is rinsed with water after handling 5min at 45 DEG C, then will be after alkaline etching
Stainless steel base be put into nitric acid solution and impregnate 20s, take out be rinsed with water again later；
Then, use preset method pre-set thickness for 1.0mm copper metal powder last layer on stainless steel base surface；
Then, use preset method pre-set thickness for 4mm ceramal mixed powder last layer on copper metal powder last layer surface, thus
Form coating material on stainless steel base surface, in the ceramal mixed-powder, alloying component include be Cu, Al, Ti, W,
Ceramic composition is Al2O3And SiO2Mixture；
Finally, the coating material to stainless steel base surface carries out laser melting coating, it is passed through helium atmosphere in the process, to make
Stainless steel base surface forms composite coating.
The stainless steel base uses super austenitic stainless steel N08367.
The mass ratio of alloying component and ceramic composition is 8:1 in the ceramal mixed-powder.
The copper metal powder and ceramal mixed-powder are previously placed in baking oven and pretreatment are dried for 120 DEG C
2h。
The laser melting coating is carried out using optical fiber laser, the laser power of laser is 7kW, scanning speed 15mm/
s。
Protective atmosphere is formed using the protection gas hood of helium atmosphere, carries out the laser melting coating step.
The partial size of the ceramal mixed-powder is 15nm.
Embodiment 3:
A kind of preparation method of composite coating, comprising the following steps:
Firstly, stainless steel base is put into NaOH solution, it is rinsed with water after handling 8min at 50 DEG C, then will be after alkaline etching
Stainless steel base be put into nitric acid solution and impregnate 25s, take out be rinsed with water again later；
Then, use preset method pre-set thickness for 0.5mm copper metal powder last layer on stainless steel base surface；
Then, use preset method pre-set thickness for 3mm ceramal mixed powder last layer on copper metal powder last layer surface, thus
Form coating material on stainless steel base surface, in the ceramal mixed-powder, alloying component include be Cu, Al, Ti, W,
Ceramic composition is Al2O3And SiO2Mixture；
Finally, the coating material to stainless steel base surface carries out laser melting coating, it is passed through helium atmosphere in the process, to make
Stainless steel base surface forms composite coating.
The stainless steel base uses super austenitic stainless steel N08367.
The mass ratio of alloying component and ceramic composition is 4:1 in the ceramal mixed-powder.
The copper metal powder and ceramal mixed-powder are previously placed in baking oven and pretreatment are dried for 120 DEG C
2h。
The laser melting coating is carried out using optical fiber laser, the laser power of laser is 7kW, scanning speed 20mm/
s。
Protective atmosphere is formed using the protection gas hood of helium atmosphere, carries out the laser melting coating step.
The partial size of the ceramal mixed-powder is 20nm.
Comparative example 1:
In the manufacturing method of the present invention, when changing the element selection of coating material, even if the step of laser melting and coating process
It remains unchanged with parameter area, also leads to the wear-resisting property of final stainless steel knife product.
Comparative example 2:
When the parameter of laser melting and coating process changes, will lead to the microstructure change of cladding layer, crystallite dimension and
Microstructure is undesirable, increases the generation of the microdefects such as hole, and product service life is caused to decline.
The results showed that the present invention is by being chemically treated, at acid it can be seen from embodiment 1-3 and comparative example 1 and 2
Laser Surface Treatment under reason and particular atmosphere improves stainless steel surface modified technique, most appropriate for stainless steel mating chemical composition
Cladding layer material and process parameters range so that final stainless steel knife finished product, not only wear-resisting and excellent anti-corrosion performance,
Microstructure is fine and close, and process costs are controllable, and service performance is fully able to meet the application demand of cutter commodity.
While there has been shown and described that the embodiment of this patent, it will be understood by those skilled in the art that: not
A variety of change, modification, replacement and modification can be carried out to these embodiments in the case where being detached from the principle and objective of this patent, this
The range of patent is defined by the claims and their equivalents.
Claims (7)
1. a kind of preparation method of composite coating, which comprises the following steps:
Firstly, stainless steel base is put into NaOH solution, it is rinsed with water after handling 2~10min at 40~50 DEG C, then by alkali
Stainless steel base after erosion, which is put into nitric acid solution, impregnates 15-30s, takes out be rinsed with water again later；
Then, use preset method pre-set thickness for 0.1~1.0mm copper metal powder last layer on stainless steel base surface；
Then, use preset method pre-set thickness for 2~4mm ceramal mixed powder last layer on copper metal powder last layer surface, thus
Form coating material on stainless steel base surface, in the ceramal mixed-powder, alloying component include be Cu, Al, Ti, W,
Ceramic composition is Al2O3And SiO2Mixture；
Finally, the coating material to stainless steel base surface carries out laser melting coating, it is passed through helium atmosphere in the process, to make stainless
Steel matrix surface forms composite coating.
2. preparation method according to claim 1, which is characterized in that the stainless steel base is stainless using super austenitic
Steel N08367.
3. preparation method according to claim 1 or 2, which is characterized in that in the ceramal mixed-powder alloy at
Dividing with the mass ratio of ceramic composition is (2~8): 1.
4. preparation method according to claim 1, which is characterized in that the copper metal powder and ceramal mixed-powder
It is previously placed in baking oven and pretreatment 2h is dried for 120 DEG C.
5. preparation method according to claim 1, which is characterized in that the laser melting coating is carried out using optical fiber laser,
The laser power of laser is 5kW~8kW, and scanning speed is 10~30mm/s.
6. according to claim 1 to preparation method described in 5, which is characterized in that formed and protected using the protection gas hood of helium atmosphere
Atmosphere is protected, the laser melting coating step is carried out.
7. according to claim 1 to preparation method described in 6, it is characterised in that: the partial size of the ceramal mixed-powder
For 10-30nm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201811103048.XA CN109136918A (en) | 2018-09-20 | 2018-09-20 | A kind of preparation method of composite coating |
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| CN201811103048.XA CN109136918A (en) | 2018-09-20 | 2018-09-20 | A kind of preparation method of composite coating |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112176337A (en) * | 2020-09-30 | 2021-01-05 | 万事泰集团(广东)技术研究有限公司 | Laser cladding biological metal ceramic pot and preparation method thereof |
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| CN112176337A (en) * | 2020-09-30 | 2021-01-05 | 万事泰集团(广东)技术研究有限公司 | Laser cladding biological metal ceramic pot and preparation method thereof |
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Application publication date: 20190104 |