CN109023223B - Metal surface bluing method using low-temperature plasma - Google Patents

Metal surface bluing method using low-temperature plasma Download PDF

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CN109023223B
CN109023223B CN201811018958.8A CN201811018958A CN109023223B CN 109023223 B CN109023223 B CN 109023223B CN 201811018958 A CN201811018958 A CN 201811018958A CN 109023223 B CN109023223 B CN 109023223B
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steel
bluing
low
cavity
temperature plasma
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CN109023223A (en
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赵�卓
赵志伟
周艳文
佟欣儒
武俊生
陈雪娇
腾越
张鑫
张豫坤
方方
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University of Science and Technology Liaoning USTL
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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
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/36—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases using ionised gases, e.g. ionitriding
    • C23C8/38—Treatment of ferrous surfaces
    • 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
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/80—After-treatment

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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)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)

Abstract

The invention aims to overcome the defects of a bluing process in the prior art, provides a metal surface bluing method by using low-temperature plasma, and belongs to the metal material surface treatment technologyThe field of operation. The method applies an electric field under a certain air pressure by using vacuum equipment to make inert gas and H2Glow discharge and ionization of O molecules are carried out to form low-temperature plasma and generate O with activation effect2+Ions. O is2+The ions are attracted by a negative potential applied to the steel or steel part and bombard the surface of the workpiece. Active O2+The ions are combined with iron on the surface of the steel workpiece to generate bluing reaction. The prepared bluing oxide film is compact and beautiful, has low cost and simple operation, is beneficial to industrial production and has no pollution. The preparation method realizes the low-temperature plasma bluing treatment and has wide application range.

Description

Metal surface bluing method using low-temperature plasma
Technical Field
The invention belongs to the technical field of metal material surface treatment, and particularly relates to a metal surface bluing method by using low-temperature plasma.
Background
The process of heating steel or steel parts in air + water vapor or chemical to a suitable temperature to form a layer of protective blue or black oxide film on the surface is called bluing, also called blackening. The existing bluing technology is complex, and the chemical used in the chemical method has great environmental pollution, thus being not beneficial to environmental protection and long-time industrial production; the method of introducing oxygen to bluing is inconvenient to operate due to the fact that more parameters need to be controlled. Resulting in poor bluing effect on the surface of steel or steel parts, poor appearance of the formed oxide film, or defective oxide film, which affects the corrosion prevention effect.
Disclosure of Invention
The invention aims to overcome the defects of a bluing process in the prior art and provides a metal surface bluing method by using low-temperature plasma. The method applies an electric field under a certain air pressure by using vacuum equipment to make inert gas and H2Glow discharge and ionization of O molecules are carried out to form low-temperature plasma and generate O with activation effect2+Ions. O is2+The ions are attracted by a negative potential applied to the steel or steel part and bombard the surface of the workpiece. Active O2+The ions are combined with iron on the surface of the steel workpiece to generate bluing reaction.
A metal surface bluing method using low-temperature plasma comprises the following steps:
(1) degreasing: degreasing steel or steel parts to remove surface oil stains;
preferably, the degreasing method comprises the steps of boiling and washing the steel or the steel part in a boiling degreasing solution for 20-30 min, and then washing in flowing deionized water to remove the degreasing solution on the surface of the steel or the steel part;
the formula of the degreasing solution is as follows: NaOH: 50-60 g of Na2CO3：70～80g、H2O：1L；
(2) Acid washing: pickling the degreased steel or steel part to remove rust and oxide skin on the surface of the steel or steel part and activate the surface;
preferably, the pickling treatment method comprises the steps of pickling the steel products or the steel parts in industrial hydrochloric acid with the mass concentration of 20-35%, wherein the pickling time is more than 30s, and the steel products or the steel parts are cleaned by pickling but cannot be corroded; after acid washing, washing the steel or the steel part by deionized water, and then adding Na with the mass concentration of 3-5%2CO3Neutralizing residual acid in the solution, wherein the surface of the steel material or steel part subjected to acid pickling is silver gray;
further, urea with the mass of 0.2-0.5% of the mass of the hydrochloric acid is added into the industrial hydrochloric acid;
(3) bluing: the specific process is as follows:
(3.1) putting the degreased and pickled steel or steel part into a cavity of a low-temperature plasma generator;
(3.2) evacuating the cavity to reach 3 × 10-3Pa below;
(3.3) heating the cavity, and drying the steel or the steel part;
(3.4) introducing Ar gas into the cavity, wherein the Ar gas is 150-250 sccm, turning on a substrate bias power supply, and allowing the Ar gas to bombard the surface of the steel material or the steel part in an ionized mode to achieve the purpose of cleaning and activating the surface of the steel material or the steel part, wherein the bombardment is performed for 10-15 min under the low bias voltage of-100-120V and for 20-30 min under the high bias voltage of-280-300V;
(3.5) introducing H into the cavity2O steam with the size of 150-250 sccm;
(3.6) turning on a filament to switch on current, adjusting the current of the filament to be (4.5-5) A4, controlling the air pressure of the cavity to be 0.3-0.5 Pa, and carrying out bluing under the working air pressure for 45-60 min;
(4) saponification: the steel material or the steel part after the bluing is saponified, so that iron in micropores of an iron oxide film generated by bluing the steel material or the steel part is converted into ferric stearate in a passivated state, and the corrosion resistance is improved;
preferably, the saponification treatment method comprises the steps of immersing the steel material or the steel piece after bluing in boiling soap water with the mass concentration of 2-3% for 3-5 min, and then drying;
(5) oil immersion: performing oil immersion treatment on the saponified steel or steel part to form an oil film on the surface;
preferably, the oil immersion treatment method comprises the steps of immersing the saponified steel or steel part into hot oil at the temperature of 105-115 ℃ for 1-3 min, and removing water to form an oil film.
Compared with the prior art, the invention has the beneficial effects that:
1. the preparation method of the invention applies an electric field under certain air pressure by utilizing vacuum equipment to lead inert gas and H2Glow discharge and ionization of O molecules are carried out to form low-temperature plasma and generate O with activation effect2+Ions. O is2+The ions are attracted by the negative potential applied to the steel workpiece and bombard the surface of the workpiece. Active O2+The ions are combined with iron on the surface of the steel workpiece to generate bluing reaction. Prepared blueingThe oxide film is compact and beautiful, the cost is low, the operation is simple, the method is beneficial to industrial production, and no pollution is caused.
2. The preparation method realizes the low-temperature plasma bluing treatment and has wide application range.
Detailed Description
Example 1
A metal surface bluing method using low-temperature plasma comprises the following steps:
(1) degreasing: boiling and washing the steel or the steel piece in boiling degreasing solution for 20min, and then washing in flowing deionized water to remove the degreasing solution on the surface of the steel or the steel piece so as to remove surface oil stains;
the formula of the degreasing solution is as follows: NaOH: 50-60 g of Na2CO3：70～80g、H2O：1L；
(2) Acid washing: pickling steel or a steel part in industrial hydrochloric acid which is added with urea with the mass of 0.2% of that of the hydrochloric acid and has the mass concentration of 20% for 60 s; after acid washing, the steel or the steel part is washed by deionized water and then is added with Na with the mass concentration of 3 percent2CO3Neutralizing residual acid in the solution, wherein the surface of the steel or the steel part subjected to acid pickling is silver gray so as to remove rust and oxide skin on the surface of the steel or the steel part and activate the surface at the same time;
(3) bluing: the specific process is as follows:
(3.1) putting the degreased and pickled steel or steel part into a cavity of a low-temperature plasma generator;
(3.2) evacuating to 1 × 10-3Pa；
(3.3) heating the cavity, and drying the steel or the steel part;
(3.4) introducing Ar gas with the size of 150sccm, turning on a substrate bias power supply to enable the Ar gas to bombard the surface of the steel material or the steel part in an ionized mode to realize the purpose of cleaning and activating the surface of the steel material or the steel part, bombarding for 10min under the low bias voltage-100V state, and bombarding for 20min under the high bias voltage-280V state;
(3.5) introducing H into the cavity2O steam with the size of 150 sccm;
(3.6) turning on a filament to switch on current, adjusting the current of the filament to 4.5A 4, adjusting the air pressure of a cavity to 0.5Pa, and carrying out blue-emitting under the working air pressure for 45 min;
(4) saponification: immersing the steel or the steel part after bluing in soap water with the boiling mass concentration of 2% for 5min, and then drying to convert iron in micropores of an iron oxide film generated by bluing the steel or the steel part into ferric stearate in a passivation state, thereby improving the corrosion resistance;
(5) oil immersion: soaking the saponified steel or steel piece into hot oil at 115 deg.C for 1min, removing water to form oil film, and forming oil film on the surface.
Through detection, the oxide film is dark blue, uniform, attractive and free of dead spots; the average film thickness is 1.1 μm; the film component is Fe3O4(ii) a The depth of the etching was 0.102 mm/a.
Example 2
A metal surface bluing method using low-temperature plasma comprises the following steps:
(1) degreasing: boiling and washing the steel or the steel piece in boiling degreasing solution for 30min, and then washing in flowing deionized water to remove the degreasing solution on the surface of the steel or the steel piece so as to remove surface oil stains;
the formula of the degreasing solution is as follows: NaOH: 50-60 g of Na2CO3：70～80g、H2O：1L；
(2) Acid washing: pickling steel or a steel part in industrial hydrochloric acid which is added with urea with the mass of 0.5% of that of the hydrochloric acid and has the mass concentration of 35% for 35 s; after acid washing, the steel or the steel part is washed by deionized water and then is added with Na with the mass concentration of 5 percent2CO3Neutralizing residual acid in the solution, wherein the surface of the steel or the steel part subjected to acid pickling is silver gray so as to remove rust and oxide skin on the surface of the steel or the steel part and activate the surface at the same time;
(3) bluing: the specific process is as follows:
(3.1) putting the degreased and pickled steel or steel part into a cavity of a low-temperature plasma generator;
(3.2) evacuating to 1 × 10-3Pa；
(3.3) heating the cavity, and drying the steel or the steel part;
(3.4) introducing Ar gas with the size of 250sccm, turning on a substrate bias power supply to enable the Ar gas to bombard the surface of the steel material or the steel part in an ionized mode to realize the purpose of cleaning and activating the surface of the steel material or the steel part, bombarding for 15min under the low bias voltage-120V state, and bombarding for 30min under the high bias voltage-300V state;
(3.5) introducing H into the cavity2O steam with the size of 250 sccm;
(3.6) turning on a filament to switch on current, adjusting the current, wherein the filament current is 5A 4, the air pressure of the cavity reaches 0.3Pa, and carrying out blue-emitting under the working air pressure for 1 h;
(4) saponification: immersing the steel or the steel part after bluing in boiling soap water with 3% of mass concentration for 3min, and then drying to convert iron in micropores of an iron oxide film generated by bluing the steel or the steel part into ferric stearate in a passivation state, thereby improving the corrosion resistance;
(5) oil immersion: immersing the saponified steel or steel piece into hot oil at 105 deg.C for 3min, and removing water to form oil film on the surface.
Through detection, the oxide film is dark blue, uniform, attractive and free of dead spots; the average film thickness is 1.5 mu m; the film component is Fe3O4(ii) a The depth of the etching is 0.091 mm/a.
Example 3
A metal surface bluing method using low-temperature plasma comprises the following steps:
(1) degreasing: boiling and washing the steel or the steel piece in boiling degreasing solution for 25min, and then washing in flowing deionized water to remove the degreasing solution on the surface of the steel or the steel piece so as to remove surface oil stains;
the formula of the degreasing solution is as follows: NaOH: 50-60 g of Na2CO3：70～80g、H2O：1L；
(2) Acid washing: pickling steel or steel parts in 27 mass percent industrial hydrochloric acid added with urea with the mass of 0.3 percent of the mass of the hydrochloric acid for 50 s; after acid washing, the steel or the steel part is washed by deionized water and then is added with Na with the mass concentration of 4 percent2CO3Neutralizing residual acid in solution, pickling steel or steel surfaceThe surface is silver gray to remove rust and oxide skin on the surface of steel or a steel part and activate the surface at the same time;
(3) bluing: the specific process is as follows:
(3.1) putting the degreased and pickled steel or steel part into a cavity of a low-temperature plasma generator;
(3.2) evacuating to 1 × 10-3Pa；
(3.3) heating the cavity, and drying the steel or the steel part;
(3.4) introducing Ar gas with the size of 200sccm, turning on a substrate bias power supply to enable the Ar gas to bombard the surface of the steel material or the steel part in an ionized mode to realize the purpose of cleaning and activating the surface of the steel material or the steel part, bombarding for 13min under the low bias voltage of minus 110V, and bombarding for 25min under the high bias voltage of minus 290V;
(3.5) introducing H into the cavity2O steam with the size of 200 sccm; (ii) a
(3.6) turning on a filament to switch on current, adjusting the current, wherein the filament current is 4.8A 4, the air pressure of the cavity is 0.4Pa, and carrying out blue-emitting under the working air pressure for 52 min;
(4) saponification: immersing the steel or the steel part after bluing in boiling soap water with the mass concentration of 2.5% for 4min, and then drying to convert iron in micropores of an iron oxide film generated by bluing the steel or the steel part into ferric stearate in a passivation state, thereby improving the corrosion resistance;
(5) oil immersion: soaking the saponified steel or steel piece into hot oil at 110 deg.C for 2min, removing water to form oil film, and forming oil film on the surface.
Through detection, the oxide film is dark blue, uniform, attractive and free of dead spots; the average film thickness is 1.3 mu m; the film component is Fe3O4(ii) a The depth of the etching is 0.096 mm/a.

Claims (6)

1. A metal surface bluing method using low-temperature plasma is characterized by comprising the following steps:
(1) degreasing: degreasing steel or steel parts to remove surface oil stains;
(2) acid washing: pickling the degreased steel or steel part to remove rust and oxide skin on the surface of the steel or steel part and activate the surface;
(3) bluing: the specific process is as follows:
(3.1) putting the degreased and pickled steel or steel part into a cavity of a low-temperature plasma generator;
(3.2) evacuating the cavity to reach 3 × 10-3Pa below;
(3.3) heating the cavity, and drying the steel or the steel part;
(3.4) introducing Ar gas into the cavity, wherein the Ar gas is 150-250 sccm, turning on a substrate bias power supply to enable Ar gas to bombard the surface of the steel or the steel piece in an ionized mode, bombarding for 10-15 min under the low bias voltage of-100-120V, and bombarding for 20-30 min under the high bias voltage of-280-300V;
(3.5) introducing H into the cavity2O steam with the size of 150-250 sccm;
(3.6) turning on a filament to switch on current, adjusting the current of the filament to be (4.5-5) A4, controlling the air pressure of the cavity to be 0.3-0.5 Pa, and carrying out bluing under the working air pressure for 45-60 min;
(4) saponification: saponifying the steel or the steel part after the bluing to convert iron in micropores of an iron oxide film generated by bluing the steel or the steel part into ferric stearate;
(5) oil immersion: and (3) performing oil immersion treatment on the saponified steel or steel part to form an oil film on the surface.
2. The method for bluing a metal surface according to claim 1, wherein the degreasing treatment in step (1) is performed by boiling the steel material or the steel member in a boiling degreasing solution for 20 to 30min, and then rinsing the steel material or the steel member in flowing deionized water to remove the degreasing solution on the surface of the steel material or the steel member;
the formula of the degreasing solution is as follows: NaOH: 50-60 g of Na2CO3：70～80g、H2O：1L。
3. The method for bluing a metal surface according to claim 1, wherein the acid washing treatment in the step (2) is performed by subjecting the steel material or the steel member to a treatment at a mass concentration of 20 to 35%Pickling in industrial hydrochloric acid for more than 30s until the product is clean but cannot be corroded; after acid washing, washing the steel or the steel part by deionized water, and then adding Na with the mass concentration of 3-5%2CO3The solution neutralizes the residual acid.
4. The method for bluing a metal surface according to claim 3, wherein urea is further added to the industrial hydrochloric acid in an amount of 0.2 to 0.5 mass% based on the mass of the hydrochloric acid.
5. The method for bluing a metal surface according to claim 1, wherein the saponification treatment in step (4) is performed by immersing the bluing steel material or steel member in boiling soap water having a mass concentration of 2 to 3% for 3 to 5min and then drying the steel material or steel member.
6. The method for bluing a metal surface according to claim 1, wherein the oil immersion treatment in step (5) is performed by immersing the saponified steel material or steel member in hot oil at 105-115 ℃ for 1-3 min to remove water and form an oil film.
CN201811018958.8A 2018-09-03 2018-09-03 Metal surface bluing method using low-temperature plasma Active CN109023223B (en)

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