JPH03291377A - Production of steel sheet having film extremely excellent in wear resistance - Google Patents

Abstract

PURPOSE:To produce a steel sheet having a film extremely excellent in wear resistance by successively forming a metallic film, a ceramic film, and a diamond film on the surface of a steel sheet by means of ion plating on an HCD system. CONSTITUTION:A metallic film of Cr, Ti, etc., is formed to about 0.01-5mu thickness on the surface of a surface treated steel sheet 8 (low carbon steel, etc.) by means of ion plating treatment on an HCD system, and further, a ceramic film of CrN, CrC, TiN, TiC, Ti(C,N), etc., is formed to about 0.01-5mu thickness on the above. This steel sheet 8 is disposed in a vacuum chamber 6 and an HCD plasma beam is produced from an HCD gun 1 by using an electrode 2 and an electromagnet 4, and then, the surface of the steel sheet 8 is irradiated with a high plasma electron current 5 by the action of a permanent magnet 9. On the other hand, the ionization, e.g. of a gaseous mixture of CH4 and H2 is accelerated by using an activation nozzle 10 in which the nozzle end is electrically heated, and these ions are supplied onto the surface of the steel sheet 8, by which a diamond film is formed.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention provides a method of applying
The present invention relates to a method of forming a coating having extremely excellent wear resistance, corrosion resistance, and adhesion.

(Prior Art) In recent years, coating technology using plasma has made significant progress, and its use is becoming widespread in various fields. Applications of such coating techniques include, for example, the formation of magnetic recording thin films, various wear-resistant and corrosion-resistant coatings, and decorative coatings.

Normally, when plasma is used, it is possible to ionize or activate evaporated substances such as metals and semimetals, and to impart high kinetic energy. can get.

Conventionally, plasma coating methods include magnetron sputtering and EB (Electron Beam).
) In addition to the RF (Radio Frequency) method and the plasma CVD method, recently the multi-arc method using a vacuum arc and the hollow cathode () f
olow CathodeDischarge, :
Ion plating using a method (simply referred to as HCD) is known.

In order to use these methods to form a ceramic coating with excellent properties such as adhesion, uniformity, and corrosion resistance on the surface of a large steel plate, ionization is necessary during ion plating or ion implantation treatment. It is fundamentally important to improve the rate, increase the voltage applied to the steel plate, and increase the temperature of the steel plate.

The coating film obtained through such treatment has film quality,
Although adhesion and corrosion resistance have been significantly improved, it is still difficult to say that sufficient adhesion and corrosion resistance have been obtained, and in particular, sufficient wear resistance has not been obtained. Improvements in the layers were requested.

In particular, the ion plating process using the HCD method is
Because it has a relatively high ionization rate and a high film formation rate, it is advantageous for use in steel plates with large surface areas used for construction materials, etc. It is also useful because it can be expected to improve corrosion resistance, decorativeness, and abrasion resistance. Although attempts have been made, it has not yet been put into practical use.

The reasons for this are: 1) good adhesion between the steel plate and the ceramic coating, 2) ability to uniformly coat a large surface area with the ceramic coating, 3) good quality of the ceramic coating, and 4) wear resistance. , excellent corrosion resistance, and 5) the ability to form a film at high speed on a steel plate with a large surface area and the ability to perform coating in a favorable plasma atmosphere. However, it was not possible to fully satisfy these conditions.

Separately, studies have recently been conducted on the physical properties of surface treatment #4#Ii by the ion plating method using the arc discharge method. It has been reported that a significant improvement in corrosion resistance was observed compared to layer coatings. (Refer to Hiroshi Kagechika, Hiroshi Kibe, Takeshi Ayasuya, Hiroshi Naemura, and Hiroshi Haratomi: Tetsu to Tsuna, 72 (1986), 51309). On the other hand, JP-A-62-99458 states: 1. OXl0-
A process of forming a first plating layer by performing ion plating in a high vacuum atmosphere of 'Torr or less, and a method of forming a plating layer of a material different from the first layer on the coating are disclosed. However, such ion plating method reduces the atmospheric pressure in vacuum to 1. OXl0-'T
Since it is necessary to create a high vacuum of less than orr, there is a problem in applying it to an actual industrial scale process.

Furthermore, very recently, after nitric acid electrolytic treatment, stainless steel plates have been
A coating of 5iO1 or 5iJa is applied by plasma CVD (Hashimoto et al.: CAMP-l5IJ.

Vol. 1 (1988), P426 and JP-A No. 63-62860) and corrosion resistance is reported to be improved.

However, since this method usually performs ion bombardment treatment before dry rating treatment, the electrolytic treatment effect on the surface of the steel sheet disappears, and furthermore, a passive film is formed on the surface of the stainless steel sheet, which causes the bond between the steel sheet and the ceramic coating. There were still many problems that needed to be resolved before it could be used in actual production processes, such as poor adhesion between the two.

(What the invention is trying to solve!) As a solution to the problems of the prior art described above, the inventor has developed a ceramic coating with excellent corrosion resistance and adhesion by using the HCD method, which has a modified transfer route for evaporated substances. A method for manufacturing such a steel plate was proposed in Japanese Patent Application No. 63-203924.

However, this method was not necessarily sufficient to meet the high requirements regarding wear resistance.

Therefore, an object of the present invention is to propose a method for advantageously forming a coating having extremely excellent wear resistance, corrosion resistance, and adhesion on a large surface area carbon steel plate or stainless steel plate.

(Means for solving !III!!!) As a result of intensive research to solve the above problem, the inventor found that in order to achieve the intended purpose, the above-mentioned) ICD method was used. C with good adhesion when performing ion plating
It has been found that it is extremely effective to utilize a combination of a base metal coating such as r or Ti, a ceramic coating of Cr or Ti, and a diamond thin film.

That is, this invention forms a metal film on the surface of a steel plate by ion plating treatment using the HCD method, and then forms a ceramic film such as Cr or Ti carbide, nitride, or carbonitride on this film. Furthermore, the surface of the ceramic coating is irradiated with a beam using the HCD method, and at the same time, a mixed gas of hydrocarbon and hydrogen is supplied from an activation nozzle whose tip is electrically heated to coat the ceramic coating with a diamond thin film. This is a method for producing a steel plate having a coating with extremely excellent wear resistance.

Here, the metal coating is preferably Cr or Ti, and the thickness of each of the metal coating, ceramic coating, and diamond thin film is preferably in the range of 0.01 μ- to 5 μ-, and the mixing ratio of hydrocarbon and hydrogen is is a volume ratio of hydrocarbon to hydrogen, which is preferably in the range of 0.05 to 0.5.

(Function) This invention has extremely excellent wear resistance, corrosion resistance,
In order to obtain a steel sheet with a film that has excellent adhesion, prior to forming a diamond thin film on the surface of the steel sheet, a metal film is formed as a base layer, and a ceramic is further formed on top of the metal film. In addition, it is important to use ion plating using the HCD method for depositing metal coatings, ceramic coatings, and diamond thin films.

This invention will be specifically explained below.

After performing recrystallization annealing including cold rolling using a low carbon steel plate or stainless steel plate, the steel plate surface is cleaned by grinding or polishing, and then adhered to the steel plate by ion plating using the fcD method. Cr with good properties
, Ti, etc. is coated with a thickness ranging from 0.01 μM to 5 μM steel, and then CrN is deposited on top of it.

A ceramic film such as CrC, TiN, TiC and Ti (C,N) is formed to a thickness of 0.01 μm to 5 μm, and then a diamond film is further applied to a thickness of 0.0 μm.
It is preferable to form the coating with a thickness in the range of 1 μm to 5 μm.

If the thickness of each of the metal coating, ceramic coating, and diamond thin film is less than 0.01 am, the desired effect will not be obtained, and if it exceeds 5 μm, the hardness will be high, so it will not be able to withstand tension, compression, or impact. However, the thin film tends to break easily, and making it thicker than necessary is also uneconomical. Therefore, the thickness is preferably 5 μm or less.

Next, an example of the method for forming a diamond thin film will be explained with reference to FIG. 1, which is a schematic diagram of a diamond thin film manufacturing apparatus using a pressure gradient HCD method. That is, from the HCD gun l, electrodes 2°3,! H using m magnet
A CD plasma beam beam is generated, and a permanent magnet 9 provided behind the substrate 8 is used to irradiate the surface of the substrate 8 with a high plasma electron flow as shown by the dotted line 5. On the other hand, an activation nozzle 10 whose tip is electrically heated is used to promote ionization of a mixed gas of, for example, CL and H2, and the ionized gas is supplied onto the substrate surface to form a diamond thin film.

Here, as conditions for obtaining a diamond thin film in the above apparatus, the voltage and current conditions of the HCD gun are as follows: voltage: IOV to 100V, current: 200A to 30V, respectively.
The electrical heating conditions at the tip of the activation nozzle are preferably in the range of voltage: 20V to 60V, current = 10^ to 5OA, and the ionization of the gas is promoted under these conditions. In addition, the mixing ratio of at least one of hydrocarbons, CI (4, Cfh, CH, etc.) and hydrogen is preferably in the range of 0.05 to 0.5 by volume of hydrogen to 1 part of hydrocarbon, and the gas flow rate is 300cc/sin to 3000cc
A range of 10+in is desirable.

Here, if the mixing ratio of hydrocarbon and hydrogen is less than 0.05 hydrocarbon to 1 hydrogen by volume, the concentration will be low and the effect will be insufficient, and if it exceeds 0.5, the C component will be excessive and the inside of the furnace will be To prevent staining, a value of 0.5 or less is desirable.

Next, the experimental results that formed the basis of this invention will be explained.

C: 0.049wtχ, Si: 0.18wLχ,
Mn: 0.3211tX, Cr: 17.1wt
X, P: 0.018wtχ, S: 0.00
A 2.2-inch thick hot-rolled stainless steel plate containing 4wtχ was cold-rolled to a thickness of 0.25-inch, and then recrystallized annealed in an inert atmosphere at 750°C, followed by the following a and b. ,c
.

Each film was formed on the surface of the steel plate using seven methods shown in d, e, f, and g.

Note a. Ti is evaporated by electron beam (simply referred to as EB) scanning, and then RF (Radio Freq)
ionization using a TiN coating (
The film was formed by the so-called EB + RF method, which coats the film with a thickness of 1.0 pyi. The processing conditions are vacuum degree 3 x 1
The irradiation conditions for 0-'Torr and EB (pierce type) were as follows: acceleration voltage: 60KV, acceleration current: 5p^, and RF power for N2 gas ionization was 1000V.

b. From EB constant scanning, a Cr coating (0.5μ
EB+
Film formation was performed using the RF method. Here, the processing conditions for the first layer Cr film are vacuum degree 4 x 10-'Torr, EB
(Pierce type) irradiation conditions were acceleration voltage: 60KV, acceleration current: 5mA, and the second layer TiN coating was formed under the same EB conditions as above, with the RF power for N2 gas ionization being 1000- And so.

Furthermore, using an ion plating device using the HCD method, an HCD beam was irradiated onto the surface of the substrate having the TiN film on the TiN film, and at the same time, C1 and H2 were irradiated using an activation nozzle whose nozzle tip was electrically heated. A mixed gas was supplied to form a diamond thin film with a thickness of about 0.2 μm on the surface of the substrate. At this time, a voltage of 50 V and a current of 700 A were applied to the HCD gun, and a voltage of 20 V and a current of 40 A were applied to the activation nozzle. Also, the mixed gas of CH4 and H2 has a volume ratio of 0.5 (CH4): I rug
), and the gas flow rate was 500 cc/5 h.

c. After forming a Ti film with a thickness of 0.5μ on the steel plate surface using an ion plating device using the HCD method,
A TiN film with a thickness of 1 .mu.m was overlaid thereon. The conditions for the ion plating process using the HCD method at this time were acceleration voltage = 70v, acceleration current: 1000A, degree of vacuum: 4.9 x 10-' Torr, and bias voltage: 50v.

d. After forming a Cr film with a thickness of 0.5μ■ on the surface of the steel plate using an ion plating device using the IIcD method,
A TiN film having a thickness of 0.5 .mu.m was overlaid thereon.

The ion plating processing conditions using the HCD method at this time were: acceleration voltage near 0V, acceleration current: 1000A,
Vacuum degree: 5.2 x 10-'Torr and bias voltage: 50v.

Approximately 0.2μ■ under the same conditions as on the TiN film.
A thick diamond film was deposited.

e. After forming a Cr film with a thickness of 0.5μ on the surface of the steel plate using an ion plating device using the HCD method,
A TiN film having a thickness of 0.5 .mu.m was overlaid thereon.

The ion plating processing conditions using the HCD method at this time were the same as those in d.

t,) After forming a Ti film with a mist thickness of 0.5μ on the steel plate surface using an ion plating device using the HCD method,
A TiN film having a regular thickness of 1 μm was overlaid thereon.

The ion plating processing conditions using the HCD method at this time were: acceleration voltage: 68V, acceleration current: 1000A.
, degree of vacuum: 6 Xl0-'Torr, and bias voltage: 50V.

Furthermore, using an ion plating device using the HCD method, the HCD beam is irradiated onto the surface of the substrate having the TiN film on the TiN film, and at the same time, CH and H2 are mixed from an activated nozzle whose nozzle tip is electrically heated. Gas was supplied to form a diamond thin film with a thickness of about 0.2 .mu.m on the surface of the substrate. At this time, a voltage of 50 V and a current of 100 OA were applied to the HCD gun, and a voltage of 50 V and a current of 2 OA were applied to the activation nozzle. Also, CH, and H
The volume ratio of the mixed gas in step 2 is 0.5 (C)! , ) : 1
(H2), and the gas flow rate was 500 cc/win.

g. Using an ion plating device using the HCD method, a 0.5 μm thick Cr film was formed on the surface of the steel plate, and then a 0.3 μm thick TiN film was overlaid thereon.

The ion plating conditions using the HCD method at this time were the same as f.

Furthermore, a diamond thin film was formed on the TiN film under the same conditions as f.

Regarding the steel plate having the coating obtained by each of the above-mentioned treatments,
Table 1 shows the results of examining corrosion resistance, adhesion, and abrasion resistance.

In the abrasion test method, the color difference on the coating surface before the test and the color difference on the coating surface after the abrasion test were measured, and the change in color difference was expressed as a Δε value.

As is clear from Table 1, sample b was coated with a metal coating (Cr, Ti), a ceramic coating (TiN), and a diamond thin film as the outermost layer on the steel plate surface in this order from the bottom.

It is noteworthy that d, f, and g have extremely improved wear resistance. In particular, the ΔE value, which indicates the quality of wear resistance, was 0.2 to 0.3, and sample a, which was not coated with a diamond thin film,
1/10 to 1/ compared to 3.0 to 7.0 for c and e.
35, a huge improvement.

In addition, except for b, samples d, f, and g have excellent corrosion resistance and adhesion, but even with the diamond thin film, metal coating and ceramic coating were not done using the HCD method.
The sample has poor corrosion resistance.

In this way, wear resistance is significantly improved, and corrosion resistance and
The formation of a film with excellent adhesion is due to factors such as the coating method and the quality of the ceramic film, but wear resistance can be greatly improved by forming a thin diamond film with high hardness on the ceramic film. is clear.

(Example) 1 C: 0.042wtχ, Si: 0.18wtχ,
Mn: 0.33wtχ, Cr: 17. Owt$
, P: 0.016wtχ, S: 0.015wt
A 2-3 am thick stainless steel hot-rolled plate containing χ,
After cold rolling to a thickness of 0.25 m and recrystallization annealing in an inert atmosphere at 750°C,
．． A Cr film with a thickness of 0.5 μm is formed on it, and a 0.6 μm thick Cr film is formed on it.
A thick TiN film was formed, and a 0.3 μm thick diamond thin film was further formed thereon.

The thus obtained product had good corrosion resistance, adhesion, and abrasion resistance, and in particular, the abrasion resistance was extremely good, with a color difference change ΔE of 0.1 after 3000 cycles.

Implemented JLL C: 0.045wtχ, Si: 0.029wtχ
, Mn: 0.30wtχ, P: 0.014wt
χ, S: 2,2 am containing 0.016wtX
A thick low carbon steel hot rolled plate was cold rolled to a thickness of 0.7 ann,
After recrystallization annealing at 750°C, the surface of the steel plate was polished to a centerline average roughness Ra of 0.2 μM by electric field polishing, and then a Cr film with a thickness of 0.3 μm was formed under the conditions of d above. On top of that, a TiC film and a TiC film each having a thickness of 0.8 μm are applied.
A (C,N) film was formed, and a 0.2 μm thick diamond thin film was further formed thereon.

The corrosion resistance, adhesion, and abrasion resistance of the thus obtained product are all good. In particular, regarding the abrasion resistance, the color difference change ΔE after 3000 cycles is 0.3. In the case of Ti(C,N), it was 0.4, which was extremely good.

C: 0.013wtχ, Si: 0.008wtχ
, Mn: 0.21wtχ, Cr: 16.7wt
χ, P: 0.009wtχ, S: 0.016w
A 2.2 m thick hot rolled stainless steel plate containing tZ,
After cold rolling to a thickness of 0.20 mm and recrystallization annealing in an inert atmosphere at 800°C, a Ti film having a thickness of 0.07 μm was formed under the conditions of f above. A 5 μl TiC film was formed, and a 0.2 μm thick T1CN film was formed thereon, followed by a 0.2 μm thick diamond film.

The thus obtained product had good corrosion resistance, adhesion, and abrasion resistance, and in particular, the abrasion resistance was extremely good, with a color difference change ΔE of 0.2 after 5000 cycles.

Implementation flame ↓ C: 0.013wtχ, Si: 0.26evtX
, Mn: 0.25wtχ, Cr: 19.3w
tχ, Mo: 0.7 am containing 3.2wtχ
A 0.5 μm thick steel plate was coated on a 0.5 μm thick stainless steel plate under the conditions of g above, and a 0.5 μm thick CrN film was formed on top of that, and a 0.2 μm thick CrC film was further applied on top of that. After adulthood,
A 0.15 μm thick diamond coating was applied. The corrosion resistance, adhesion, and abrasion resistance of the thus obtained product were all good, and in particular, the abrasion resistance was extremely good, with E for color difference change after 10,000 cycles being 0.3.

(Effect of the invention) According to this invention, by ion plating using the HCD method on the surface of a copper plate such as carbon steel or stainless steel,
By sequentially applying a metal coating, a ceramic coating, and then a diamond coating as the outermost layer, a steel plate with excellent wear resistance, corrosion resistance, and adhesion can be obtained.
It can also be suitably used for steel plates with a large surface area used in construction, etc., and will greatly contribute to the practical application of ion plating.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a diamond thin film manufacturing apparatus using the pressure gradient type HCD method of the present invention. 1...HCD gun 2...First electrode 3...
・Second pole 4...Electromagnet 5...Beam
6... Vacuum chamber 7... Vacuum suction port 8... Substrate 9... Permanent magnet 10
...Activation nozzle 11 ... Nozzle protection tube 12
...Gas inlet diagram 1

Claims (1)

[Claims] 1. A metal coating is formed on the surface of the steel plate by ion plating treatment using the HCD method, and then carbon is applied on this coating.
A ceramic coating such as carbide, nitride, or carbonitride of Ti or Ti is coated, and the surface of the ceramic coating is irradiated with a beam by the HCD method, and at the same time, from an activation nozzle whose tip is electrically heated. A method for manufacturing a steel plate having a coating with extremely excellent wear resistance, which comprises supplying a mixed gas of hydrocarbon and hydrogen to form a diamond thin film on the ceramic coating.