CN105861976B - One kind preparing the technical method of Ti (CN) coating in stainless steel surface - Google Patents

One kind preparing the technical method of Ti (CN) coating in stainless steel surface Download PDF

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CN105861976B
CN105861976B CN201610188237.6A CN201610188237A CN105861976B CN 105861976 B CN105861976 B CN 105861976B CN 201610188237 A CN201610188237 A CN 201610188237A CN 105861976 B CN105861976 B CN 105861976B
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coating
stainless steel
prefabricated
prepare
steel surface
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CN105861976A (en
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潘太军
沈杰
陈杨
左小伟
陈婧
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Dongguan Jiujuxing Nano Coating Co ltd
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Changzhou University
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    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C4/00Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/02Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C4/00Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/04Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
    • C23C4/10Oxides, borides, carbides, nitrides or silicides; Mixtures thereof
    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C4/00Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/18After-treatment

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Coating By Spraying Or Casting (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)

Abstract

The invention belongs to Laser Surface Modification Technology fields, and in particular to a kind of process for preparing cermet carbon, nitride coatings.First by plasma spraying technology in Ti (CN) coating that prefabricated one layer of stainless steel surface is 10~20 μ m-thicks; then laser remolten processing is carried out to prefabricated brittleness Ti (CN) coating under nitrogen protection; Ti (CN) coating and matrix obtained by this technical process is metallurgical bonding; hardness height, surface compact; have good toughness, preferably protects stainless steel base.Present invention process is reproducible, feasible process, and the low carbonitride coating of high rigidity, the brittleness of acquisition has further widened the application range of stainless steel.

Description

One kind preparing the technical method of Ti (CN) coating in stainless steel surface
Technical field
The invention belongs to Laser Surface Modification Technology fields, and in particular to a kind of to prepare cermet carbon, nitride coatings Process.
Background technique
Stainless steel is as a kind of widely used metal material, due to its excellent mouldability, corrosion resistance and very wide Obdurability in temperature range so that it all occupy in heavy industry, light industry, daily necessity and architectural decoration it is important Status.However in certain environment-protecting industrials, in industrial waste gas purifying, waste incineration and sewage-treatment plant, stainless steel is faced with The test of high temperature or acidic environment tends not to meet long-time service requirement.It is a kind of for carrying out surface modification treatment to stainless steel Simply, effectively, feasible scheme.It is varied to stainless steel watch surface treatment processing method, including conversion film process, electricity Plating, ion deposition, thermal spraying etc..
Plasma spraying is smooth since the coating after its spraying is smooth, and accurately control coating layer thickness and by favor, And its technological specification is stablized, and regulation performance is good, and it is easy to operate, it is not restricted by types of coatings, scantling, crowd can be melted More high-melting-points, high rigidity powder, it is easier to large-scale industrial production.
Usual stainless steel surface modified coating includes: metal based coating;Oxide coating;Ceramic coating etc., wherein ceramics Coating due to high-melting-point, high stability and in high temperature or acidic environment to stainless steel base have good protecting effect. Compared with TiN, Ti (CN) has lower coefficient of friction and higher hardness, and excellent in wear resistance, high temperature resistant, corrosion-resistant Property, stainless steel entirety can not influenced by depositing one layer of fine and close Ti (CN) coating in stainless steel surface using plasma spraying method On the basis of performance, extend its service life in the harsh working environment such as high temperature, acidity.
However due to cermet Ti (CN), brittleness itself is larger, and due to the painting break of plasma spraying technology preparation It falls into and is difficult to avoid that, Ti (CN) coating stress for causing plasma spraying technology to prepare is concentrated, and the brittleness Ti (CN) of formation is easy to out It splits, these defects frequently can lead to corrosive medium infiltration, influence its service performance.
Summary of the invention
Technical problem to be solved by the present invention lies in: the brittleness of cermet Ti (CN) coating is larger, and stress is concentrated easy In cracking.
In order to solve the above technical problems, the present invention provides one kind in the technique side that stainless steel surface prepares Ti (CN) coating Method reduces the brittleness of prepared coating, is integrated by continuing laser remolten processing to Ti (CN) coating postponed in advance Ti (CN) coating haveing excellent performance,
Specific steps are as follows:
(1) Ti (CN) metal ceramic powder is used, carries out plasma spraying in passing through pretreated stainless steel base surface, Prefabricated Ti (CN) coating of one layer of 10~20 μ m-thick is obtained,
Wherein, the preparation process of Ti (CN) metal ceramic powder are as follows: TiN ceramic powders are mixed with carbon dust first, wherein Carbon dust is 1.0~1.5wt% of powder total amount, and then through star row ball mill 2~3h of ball milling, revolving speed is 200~300r/min, is done It sieves take step by step using 100 mesh and 200 meshes after dry grinding, it is final to retain Ti (CN) ceramic powders that partial size is 100~200 mesh,
Stainless steel base surface preparation is divided into two steps: 1, by stainless steel base through 400~1000#SiC sand paper burnishing part It manages and goes after removing oxide layer to be cleaned with acetone, is dry;2, blasting treatment: using corundum sand to 5~8min of its surface sand-blasting process, Until matrix surface loses metallic luster, and it is cleaned and dried with acetone,
Plasma spray coating process parameter are as follows: spray distance controls between 100~130mm, spray power control 75~ In 80kW, argon gas flow velocity is 40L/min, hydrogen flow rate 15L/min, and powder feeding rate is maintained at 30g/min or so;
(2) under nitrogen protection, laser remolten processing is carried out to prefabricated Ti (CN) coating obtained in step (1), obtained Ti (CN) coating,
The parameter of laser remolten processing are as follows: adjusting laser melting coating power is 50~80W/mm2;Frequency is 6~8Hz;Electric current Pulsewidth is 4~5 μ s;Electric current 220A;3~5mm/s of sweep speed;Protective gas nitrogen flow rate is 10~20L/min,
The present invention by above-mentioned preparation process, finally obtain surface compact, with basal body binding force is good, brittleness is low Ti (CN) coating plays ideal protective effect to matrix stainless steel.
Detailed description of the invention
Fig. 1 is 304L stainless steel base material (substrate), plasma spraying Ti (CN) coating in embodiment 3 (sample 1) and laser remolten Ti (CN) coating (sample 3) are respectively in 0.3MH2SO4Corrode polarization curve in solution.
As seen from the figure relative to matrix, plasma spraying Ti (CN) coating corrosion current potential increases, and through laser weight Molten Ti (CN) coating corrosion current potential is further up.
Specific embodiment
Embodiment 1
(1) stainless steel base surface preparation
By 304L stainless steel base respectively through 400,1000#SiC sand paper grinding process, and after being cleaned and dried with acetone, it adopts With corundum sand to its surface sand-blasting process 8min, until matrix surface loses metallic luster, and it is cleaned and dried with acetone;
(2) preparation of Ti (CN) metal ceramic powder
TiN ceramic powders are mixed with carbon dust, wherein carbon dust is the 1.5wt% of powder total amount, then through star row ball mill Ball milling 3h, revolving speed 280r/min sieves taken step by step after drying and grinding using 100 mesh and 200 meshes, and the final partial size that retains is 100 Ti (CN) ceramic powders of~200 mesh;
(3) using Ti (CN) metal ceramic powder obtained in step (2), in by step (1) pretreated stainless steel Matrix surface carries out plasma spraying, obtains Ti (CN) coating of 20 μ m-thicks,
Plasma spray coating process parameter are as follows: spray distance 100mm, spray power 80kW, argon gas flow velocity are 40L/ Min, hydrogen flow rate 15L/min, powder feeding rate 30g/min.
Ti (CN) the coating surface no significant defect prepared by above-mentioned plasma spraying, is well combined with matrix.By three The print of piece plasma spraying Ti (CN) coating is clipped on the vice for padding upper cloth, then does 90 ° of bendings to test piece, as a result table Bright, when not completing first order buckling test, there is phenomenon of rupture in three pieces sample coatings.
Embodiment 2
(1) stainless steel base surface preparation
Concrete operations with embodiment 1,
(2) preparation of Ti (CN) metal ceramic powder
Concrete operations are the same as embodiment 1;
(3) using Ti (CN) metal ceramic powder obtained in step (2), in by step (1) pretreated stainless steel Matrix surface carries out plasma spraying,
Plasma spray coating process parameter are as follows: spray distance 120mm, spray power 75kW, argon gas flow velocity are 40L/ Min, hydrogen flow rate 15L/min, powder feeding rate 30g/min obtain prefabricated Ti (CN) coating;
(4) under nitrogen protection, laser remolten processing, laser are carried out to prefabricated Ti (CN) coating obtained in step (3) Cladding power is 50W/mm2;Frequency 8Hz;4 μ s of electric current pulsewidth;Electric current 220A;Sweep speed 5mm/s, protective gas nitrogen flow rate For 15L/min, Ti (CN) coating is obtained.
Ti (CN) coating and matrix in the present embodiment after laser remolten are in metallurgical bonding, but since power is smaller, scanning Rate is too fast, and surface portion coating fails complete remelting.
Ti (CN) the coating print finally obtained in three pieces the present embodiment is taken to be clipped on the vice for padding upper cloth, then to examination Piece does 90 ° of bendings (if bending increases number once without cracked), the results showed that, after completing 1~2 crooked test, There is crackle in three pieces specimen surface, shows that laser melting coating can reduce coating brittleness.
Embodiment 3
(1) stainless steel base surface preparation
Concrete operations with embodiment 1,
At this point, stainless steel base is in 0.3MH2SO4It is as shown in Fig. 1 to corrode polarization curve in solution;
(2) preparation of Ti (CN) metal ceramic powder
Concrete operations are the same as embodiment 1;
(3) using Ti (CN) metal ceramic powder obtained in step (2), in by step (1) pretreated stainless steel Matrix surface carries out plasma spraying,
Plasma spray coating process parameter are as follows: spray distance 100mm, spray power 80kW, argon gas flow velocity are 40L/ Min, hydrogen flow rate 15L/min, powder feeding rate 30g/min obtain prefabricated Ti (CN) coating of 20 μ m-thicks,
Prefabricated Ti (CN) coating is in 0.3MH2SO4It is as shown in Fig. 1 to corrode polarization curve in solution;
(4) under nitrogen protection, laser remolten processing, laser are carried out to prefabricated Ti (CN) coating obtained in step (3) Cladding power is 80W/mm2;Frequency 8Hz;4 μ s of electric current pulsewidth;Electric current 220A;Sweep speed 3mm/s, protective gas nitrogen flow rate For 15L/min, Ti (CN) coating is obtained,
Ti (CN) coating is in 0.3MH2SO4It is as shown in Fig. 1 to corrode polarization curve in solution.
Ti (CN) coating in the present embodiment after laser remolten and matrix are in metallurgical bonding, coating surface densification zero defect, Acid or hot environment can be competent at.
It takes the coating print in three pieces the present embodiment after laser remolten to be clipped on the vice for padding upper cloth, carries out bending brittleness Test (if bending increases number once without cracked), the results show that after carrying out 4 90 ° of crooked tests, three pieces Specimen surface just starts cracked, shows that laser melting coating can reduce coating brittleness.

Claims (4)

1. a kind of prepare Ti(CN in stainless steel surface) method of coating, it is characterised in that: the preparation method is that,
(1) Ti(CN is used) metal ceramic powder, plasma spraying is carried out in passing through pretreated stainless steel base surface, is obtained One layer of prefabricated Ti(CN) coating;
The Ti(CN) preparation process of metal ceramic powder is,
TiN ceramic powders are mixed with carbon dust first, wherein carbon dust is 1.0~1.5wt% of powder total amount, then through star row ball Grinding machine 2~3h of ball milling, revolving speed are 200~300r/min, are sieved taken step by step using 100 mesh and 200 meshes after drying and grinding, final to protect Staying partial size is the Ti(CN of 100~200 mesh) ceramic powders;
Plasma spray coating process parameter is,
Spray distance controls between 100~130mm, and spray power controls in 75~80kW, and argon gas flow velocity is 40L/min, Hydrogen flow rate is 15L/min, and powder feeding rate is maintained at 30g/min;
(2) under nitrogen protection, to prefabricated Ti(CN obtained in step (1)) coating progress laser remolten processing, obtain Ti (CN) coating;
Adjusting laser melting coating power is 50~80W/mm2;Frequency is 6~8Hz;Electric current pulsewidth is 4~5 μ s;Electric current 220A;Scanning 3~5mm/s of rate;Protective gas nitrogen flow rate is 10~20L/min.
2. prepare Ti(CN in stainless steel surface as described in claim 1) method of coating, it is characterised in that: in step (1), Stainless steel base surface preparation is divided into two steps,
1, by stainless steel base through 400~1000#SiC sand paper grinding process is gone after removing oxide layer to be cleaned with acetone, be dried;
2, blasting treatment
Using corundum sand to 5~8min of its surface sand-blasting process, until matrix surface loses metallic luster, and cleaned with acetone It is dry.
3. prepare Ti(CN in stainless steel surface as described in claim 1) method of coating, it is characterised in that: in step (2), Adjusting laser melting coating power is 80W/mm2
4. prepare Ti(CN in stainless steel surface as described in claim 1) method of coating, it is characterised in that: in step (2), Sweep speed 3mm/s.
CN201610188237.6A 2016-03-29 2016-03-29 One kind preparing the technical method of Ti (CN) coating in stainless steel surface Active CN105861976B (en)

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CN106544618B (en) * 2016-11-04 2019-02-05 中国兵器科学研究院宁波分院 The preparation method of stainless steel surface progress ice-covering-proof coating
CN106637045A (en) * 2016-12-19 2017-05-10 江苏泽金激光科技有限公司 Technique for preparing Co-based WC coating on metal surface

Citations (4)

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Publication number Priority date Publication date Assignee Title
CN1202534A (en) * 1998-04-17 1998-12-23 清华大学 Method of preparing ceramic coating by laser smelting coating after metal surface plasma spray
CN102268626A (en) * 2010-06-01 2011-12-07 上海工程技术大学 Method for metal surface modification
CN102277552A (en) * 2010-06-09 2011-12-14 上海工程技术大学 Metal surface treatment method employing arc-plasma spraying-laser remelting
CN103911581A (en) * 2014-03-24 2014-07-09 燕山大学 Preparation method of zirconia thermal barrier coating based on roller

Patent Citations (4)

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Publication number Priority date Publication date Assignee Title
CN1202534A (en) * 1998-04-17 1998-12-23 清华大学 Method of preparing ceramic coating by laser smelting coating after metal surface plasma spray
CN102268626A (en) * 2010-06-01 2011-12-07 上海工程技术大学 Method for metal surface modification
CN102277552A (en) * 2010-06-09 2011-12-14 上海工程技术大学 Metal surface treatment method employing arc-plasma spraying-laser remelting
CN103911581A (en) * 2014-03-24 2014-07-09 燕山大学 Preparation method of zirconia thermal barrier coating based on roller

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Title
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