JPH06299328A - Article with corrosion and wear resistant coating film - Google Patents

Abstract

PURPOSE:To provide an article with a coating film having higher corrosion and wear resistance than a conventional coating film. CONSTITUTION:A 1st layer of Cr or Ni is formed by plating on the surface of an article with adhesion in 10-100mum thickness. The 1st layer is coated with a 2nd layer consisting of Ti, Zr, Hf, V, Nb and at least one of Ta and Cr by ion plating in 0.5-2mum thickness. The 2nd layer is further coated with a 3rd layer consisting of carbides, nitrides and/or carbonitrides of Ti, Zr, Hf, V, Nb and at least one of Ta and Cr in 2-5mum thickness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to articles such as plastic molding dies, tools and machine parts, and more particularly to articles having excellent wear resistance and corrosion resistance.

[0002]

2. Description of the Related Art As means for preventing abrasion of articles such as plastic molding dies, tools and machine parts, and extending their life,
A hard coating is formed on the surface of an article by a plating method, a PVD method, a CVD method, or the like. Here, as the hard coating, a Cr or Ni coating is formed by plating,
Ti, Zr, Hf, V, N by VD method or CVD method
Forming a coating layer made of at least one kind of carbide, nitride and / or carbonitride selected from b, Ta and Cr is performed.

Further, it is also practiced to form a two-layer film in which the above-mentioned plated film and a coating layer formed by a PVD method or a CVD method are combined. By forming these hard coatings, the wear resistance of the article is improved, and the life until the article is deteriorated is extended.

[0004]

However, since minute holes are present in the hard coating, corrosion of the article base material may progress from the holes in the molding of some plastics. It is considered that the cause of the corrosion is a corrosive gas such as HCl and SO _x which is generated when the plastic material is partially decomposed during the plastic molding. This thermal decomposition of plastics and additives is remarkable especially when gas is mixed in the molten plastic fluid during injection molding, and it is considered that thermal decomposition of plastic is caused by local temperature rise due to adiabatic compression of the mixed gas. Has been. Typical resins that cause such mold corrosion include polyacetal, vinyl chloride resin, nylon resin and ABS resin (acrylonitrile, butadiene, styrene copolymer) and the like.

In the case of the plated coating, the hard Cr plating has innumerable cracks on the surface from the beginning, and although the wear resistance is improved, it is not effective against corrosion. Further, in Ni plating, the above-mentioned minute voids are eliminated by increasing the film thickness as a countermeasure against corrosion, but the hardness is insufficient, so that it is not possible to expect much effect on wear. There is.

Further, a two-layer film of a plating film and a PVD film or a CVD film is formed for the purpose of having both wear resistance and corrosion resistance. Although the corrosion resistance is improved as compared with the case where only the plating film is used, the corrosion resistance is less effective due to the cracks on the Cr plating surface. In the two-layer film with Ni plating, the thickness of the plating layer is increased to improve the corrosion resistance, but since the hardness is low, the improvement in wear resistance cannot be expected as much as in the case of hard Cr plating.

Further, in the case of a two-layer film with a plating film, PV
Depending on the film formation conditions of the D film or the CVD film, film peeling may occur and the wear resistance may be impaired. The cause of this is
Peeling may occur when the oxide film or stains generated during the plating treatment on the surface of the plating film cannot be sufficiently removed by the cleaning before the PVD treatment or the CVD treatment. Further, it is known that when the surface is polished for the purpose of removing the oxide film and dirt, the plating surface is distorted, which is released by thermal history during the PVD treatment or the CVD treatment to cause peeling.

Further, articles used in an atmosphere in contact with corrosive gases and liquids are corroded by these corrosive substances. As a measure against corrosion, stainless steel metal, which is more resistant to corrosion, has been used as the material itself of the article, but in this case, the hardness of the article is insufficient and wear tends to occur. Therefore, improvement of the surface coating of articles such as molds for plastic molding, tools and machine parts, that is, development of articles having a coating excellent in abrasion resistance and corrosion resistance has been awaited.

[0009] Therefore, an object of the present invention is to solve the problems of the above-mentioned article having a hard abrasion-resistant hard coating, and to provide an article with a higher corrosion / wear-resistant coating.

[0010]

In order to achieve the above object, an article with a corrosion-resistant and abrasion-resistant hard coating of the present invention is provided with Cr or N formed by a plating method in close contact with the surface of the article.
a first layer made of i, and Ti, Zr, Hf, V, Nb and T coated on the first layer by an ion plating method.
a second layer made of at least one metal selected from a and at least one carbide, nitride and / or carbonitride selected from Ti, Zr, Hf, V, Nb and Ta in the second layer. It is characterized in that it has a third layer made of a material.

[0011]

The material of the article used in the present invention is a pure metal or an alloy material, and is particularly effective for a steel material such as die steel which is generally used in a mold. The article according to the present invention is not limited to plastic mold dies, tools, machine parts and the like, and can be used for a wide range of applications where abrasion resistance and corrosion resistance are required.

Any known plating method can be used to form the Cr or Ni layer of the present invention. Known PVD and CVD can be used for forming the second metal layer and the third hard coating of the present invention. The ion plating method, which is a type of PVD, is also an advantageous method for forming the metal layer of the second layer, so that the hard coating of the third layer may be formed following the formation of the second layer by the ion plating method. But of course it doesn't matter.

Among the methods for forming the first layer coating used in the present invention, any known plating method may be used. For example, the following method is used. The plating method for forming a hard Cr plating film is to remove the surface stains of the material by electric field degreasing, etc. and improve the water wetness, then chromic acid 350 g / l (liter), sulfuric acid 1 g / l, silicofluoric acid 16 g In a solution containing 1 / l, temperature 35 ° C, current density 5A
This is a method of forming a coating film on the surface by applying an electric field for 1 minute under the condition of / dm ² .

Among the methods for forming the Ni plating film, the electric field Ni plating method is performed at a temperature of 40 ° C. and a current density of 0 in a solution containing 130 g / l of nickel sulfate, 15 g / l of ammonium chloride and 15 g / l of boric acid. 1 under the condition of 0.5 A / dm ²
It is a method of forming a film on the surface by applying an electric field for a minute. Further, the electroless Ni-P plating is performed at a temperature of 9 in a solution containing 30 g / l of nickel chloride, 10 g / l of sodium hypophosphite, and 50 g / l of sodium hydroxyacetate.
This is a method of forming a film on the surface by immersing it for 2 hours under the condition of 0 ° C. Then, heat treatment is performed at 342 ° C. for 2 hours to precipitate Ni ₃ P and harden the surface.

The thickness of the plating film of the first layer is preferably 10 μm to 100 μm, and usually 30 μm to 70 μm.

After forming the plating film, buffing or the like is performed to remove surface stains and oxide film and to obtain smoothness to form the second and third layers.

In the ion plating method used for forming the second and third layers, generally, a metal is evaporated, the evaporated metal is ionized, and the ionized metal molecules are accelerated by an electric field in a reactive gas atmosphere. Then, it is attached and fixed to the surface of the article.

To vaporize the metal, either resistance heating or electron gun heating provided in a commercially available ion plating apparatus may be used. The vaporized metal may be ionized by any of known cathode arc discharge, glow discharge, high frequency discharge, a method using an ionization electrode, and a hollow cathode method. Among them, the cathodic arc discharge type ion plating method is a method in which metal evaporation and ionization are performed at the same time, and the metal ionization efficiency is higher than other methods, and the same metal source is used. Since it can be placed in the vacuum container, it is particularly preferable in the case of forming a film of a different kind of metal compound after forming the metal film as in the present invention.

Further, when the heating by ion irradiation is adopted when heating the substrate prior to forming the coating, it is carried out by metal ions, and the electric field for accelerating the ionized metal ions is preferably 500V to 2000V as a voltage value. , And more preferably 800V to 1500V.

When forming the second layer of the metal coating, T
Using at least one metal selected from i, Zr, Hf, V, Nb, Ta and Cr as an evaporation source, evaporation of the metal,
Ionization may be performed under vacuum. The electric field for accelerating the ionized metal in forming the metal layer has a voltage value of 0V to 500V, preferably 0V to 200V. The thickness of the metal layer is preferably 0.5 μm to 2 μm,
Usually, it may be formed to a thickness of about 1 μm.

To prepare the hard coating of the third layer, Ti, Z
At least one metal selected from r, Hf, V, Nb, Ta and Cr is used as an evaporation source, and N is used as a reactive gas.
₂ , NH ₃ , hydrocarbons or organic compounds containing nitrogen such as (CH ₃ ) ₃ N can be used. The pressure of the reactive gas varies depending on the type of gas used, but in general, it may be appropriately selected within the range of 10 ⁻³ to 10 ¹ Torr. The value of the voltage for accelerating the ionized metal when forming the hard coating of the third layer is preferably 50 V to 700 V, and more preferably 100 V to 500 V. The thickness of the hard coating of the third layer may be 2 to 5 μm.

In the present invention, the reason why the corrosion resistance is improved when the hard coating is a three-layer coating is presumed as follows. First, when the hard Cr plating is applied to the first layer, cracks occur on the plating surface. The base metal is corroded through the cracks. It is considered that when the second layer is coated with a metal layer by an ion plating method, the cracks are filled with the metal layer and the base metal is shielded from the atmosphere in which it is used, so that the corrosion resistance is improved. Further, if the hard coating of the third layer is directly coated on the polished first layer plating surface by the ion plating method, the strain remaining during polishing is released due to the thermal history during the treatment, which is harmful to the mechanical properties. Causes film peeling. However, when a metal layer is inserted as the second layer, it is considered that this layer acts as a buffer layer and prevents peeling.

Next, when electric field Ni plating or electroless Ni-P plating is applied to the first layer, similar to hard Cr plating,
Since the hard coating of the third layer is directly coated by the ion plating method for the polishing performed before coating the second layer,
Due to the thermal history during processing, the strain remaining during polishing is released, causing film peeling that is detrimental to mechanical properties. However, when a metal layer is inserted as the second layer, it is considered that the layer acts as a buffer layer and prevents peeling. In particular, in the case of electroless Ni-P plating that is heat-treated for hardening, the amount of strain accumulated in the plating film is large, and the relaxation effect due to the insertion of the metal layer is great.

[0024]

【Example】

(Example 1) Experiment number 1-1 ... Size 17 × 17 × 2 mm,
A test piece of SKH51 high-speed steel having a Vickers hardness H _V = 850 was used as a substrate, and hard Cr plating was applied as the first layer. One surface of the test piece was buffed to a mirror finish. Then, after electric field degreasing and washing with water to remove surface stains and improve water wetting, chromic acid 350 g /
A Cr plating film was formed on the surface of the substrate by applying an electric field for 1 minute in a solution containing 1 g of sulfuric acid, 1 g / l of sulfuric acid and 16 g / l of silicofluoric acid at a temperature of 35 ° C. and a current density of 5 A / dm ² .

Next, in order to remove stains and oxides on the plated surface, buffing was performed to smooth the surface of the substrate, and then ultrasonic cleaning was performed in ethanol.

For the second layer and the third layer, the coating structure of the present invention was formed by using a cathodic arc type ion plating apparatus equipped with a Ti cathode. After setting the substrate at a predetermined position of the apparatus the reaction vessel, the reaction vessel 10 ^-5 T
Exhausted to orr.

Next, a bias voltage of 1000 V was applied to the substrate to cause arc discharge from the Ti cathode. The arc discharge current at this time was 60A. While monitoring the substrate surface temperature with an infrared radiation thermometer, arc discharge was continued for 5 minutes to vaporize and ionize Ti, and the substrate surface was sputter cleaned. Maximum 450 ° C during arc discharge
Up to the substrate surface temperature was observed. Further, the bias voltage was lowered to 150 V, and a Ti layer as a second layer was formed on the substrate for 30 minutes.

Next, the voltage application to the Ti cathode was stopped, nitrogen gas was introduced into the reaction vessel, and the pressure inside the vessel was reduced to 3
A bias voltage of 300 V was applied to the substrate while flowing a nitrogen gas so as to maintain × 10 ^-2 Torr to cause arc discharge from the Ti cathode. The arc discharge current at this time was 80A. The arc discharge continued for 1 hour. As a result, a third layer of TiN was further formed on the Ti layer.

The thicknesses of the Cr-plated first layer, the Ti second layer and the third layer formed by ion plating of the formed film were measured by the ball crater method and found to be 35 μm, 1.2 μm and 3.2 μm, respectively. there were. The Vickers hardness Hv (load: 50 g) of the film formation surface of the substrate was 2100, which was a sufficient hardness, and the abrasion amount by the pin-on-disc abrasion test was 0.179 mm ³ , which was excellent abrasion resistance. Also, the adhesion between the plating layer and the second and third layers was good. Hardness is Vickers hardness Hv (load 50g) of 1500 to 2000 or more, and wear resistance is 1 mm by a pin-on-disk wear test.
^{A value of 3} or less is sufficient.

Next, the surface of the substrate on which the coating is formed is masked with an epoxy resin except for the surface on which the coating is formed, and a salt spray test (JI
As a result of S-Z-2371), no corroded portion was confirmed. The results are shown in Table 1.

Experiment Nos. 1-2 to 1-11 ... Hard Cr plating was formed by the same method as Experiment No. 1-1, and after polishing the substrate surface, Ti, Zr, Hf, V, Nb, Ta or A Cr cathode was used to form a metal layer by changing the film forming time in the same manner as in Experiment No. 1-1, and then changing the film forming time in a nitrogen gas or acetylene gas or mixed gas atmosphere thereof to form the third layer. Forming experiment number 1-1
The same test was performed. The results are shown in Table 1.

Experiment No. 1-2 The thickness of the first layer of the obtained coating was 40 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of TiC of the third layer was 4 μm and was 3.5 μm.
The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.187 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-3 ... The thickness of the first layer of the obtained coating was 42 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of TiCN of the third layer was 5 μm and was 3.6 μm. The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.201 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-4: The thickness of the first layer of the obtained coating was 43 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrN of the third layer was 3 μm and the thickness of ZrN was 3.7 μm.
The Vickers hardness Hv was 1900, the wear amount in the wear test was 0.212 mm ³ , and no corroded portion was found in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-5 ... The thickness of the first layer of the obtained coating was 38 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrCN of the third layer was 5 μm, and the thickness of the third layer was 4.1 μm. The Vickers hardness Hv was 2200, the wear amount in the wear test was 0.178 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-6 ... The thickness of the first layer of the obtained coating was 44 μm, and the thickness of the Hf layer of the second layer was 1.
The thickness of HfN of the second layer was 2 μm and the thickness of the third layer was 3.5 μm.
The Vickers hardness Hv was 2000, the wear amount in the wear test was 0.188 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-7 The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the second Hf layer was 1.
The thickness of HfCN of the third layer was 4 μm, and the thickness of HfCN was 3.3 μm. The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.210 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-8: The thickness of the first layer of the obtained coating was 35 μm, and the thickness of the V layer of the second layer was 1.1.
The thickness of the VN of the third layer was 3.2 μm. Vickers hardness Hv is 1800, wear amount in wear test is 0.1
At 95 mm ³ , no corroded part was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-9 ... The thickness of the first layer of the obtained coating was 42 μm, and the thickness of the Nb layer of the second layer was 1.
The thickness of NbN of the third layer was 3 μm, and the thickness thereof was 4.8 μm.
The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.185 mm ³ , and no corroded portion was found in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-10 The thickness of the first layer of the obtained coating was 44 μm, the thickness of the Ta layer of the second layer was 1.7 μm, and the thickness of TaN of the third layer was 4.6 μm. It was The Vickers hardness Hv was 2600, the wear amount in the wear test was 0.178 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-11: The thickness of the first layer of the obtained coating film was 44 μm, the thickness of the Cr layer of the second layer was 1.7 μm, and the thickness of CrN of the third layer was 3.4 μm. It was The Vickers hardness Hv was 1900, the wear amount in the wear test was 0.152 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment Nos. 1-12 to 18 ... Films were formed by the same method as Experiment No. 1-1 except that the film forming time was changed, and the same test as Experiment No. 1-1 was performed. The results are shown in Table 1.

Experiment No. 1-12: The thickness of the first layer of the obtained coating was 6 μm, and the thickness of the second Ti layer was 1.5 μm.
m, and the thickness of the third layer TiN was 4.2 μm. Vickers hardness Hv is 1700, wear amount in wear test is 0.1
As a result of performing a hydrochloric acid spray test at 79 mm ³ , a significantly corroded portion was observed. The hardness and wear resistance were sufficient, but the corrosion resistance was insufficient.

Experiment No. 1-13 The thickness of the first layer of the obtained coating was 230 μm, and the Ti layer of the second layer was 1.6.
The thickness of the third layer of TiN was 3.7 μm. The Vickers hardness Hv is 2100, and the wear amount in the wear test is 1.
At 242 mm ³ , no corroded portion was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 1-14: The thickness of the first layer of the obtained coating was 57 μm, and an attempt was made to form TiN of the third layer without forming the second layer. Peeling occurred immediately after taking out. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was observed in the hydrochloric acid spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 1-15 The thickness of the first layer of the obtained coating was 57 μm, and the TiN of the second layer peeled off immediately after being taken out from the ion plating apparatus. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was observed in the hydrochloric acid spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 1-16: The thickness of the first layer of the obtained coating was 57 μm, and the thickness of the second Ti layer was 7.3 μm.
m, and the thickness of TiN of the third layer was 4.1 μm. Vickers hardness Hv is 2200, wear amount in wear test is 1.3
At 86 mm ³ , no corroded part was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 1-17: The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the second Ti layer was 1.4 μm.
m, and the thickness of TiN of the third layer was 1.3 μm. Vickers hardness Hv is 800, wear amount in wear test is 1.67
At 2 mm ³ , no corroded portion was observed in the hydrochloric acid spray test. The corrosion resistance was sufficient, but the hardness and wear resistance were insufficient.

Experiment No. 1-18 The thickness of the first layer of the obtained coating was 59 μm, and the thickness of the second Ti layer was 1.2 μm.
m, and the thickness of TiN of the third layer was 9.5 μm. Vickers hardness Hv is 2200, wear amount in wear test is 1.5
At 67 mm ³ , no corroded part was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient. The thickness of the first layer of hard Cr plating is 10 μm
If it is less than 100 μm, the corrosion resistance becomes insufficient, and if it exceeds 100 μm, the abrasion resistance becomes insufficient. Further, when the second layer was not covered and when the thickness was less than 1 μm, peeling of the third layer occurred. If the thickness of the third layer is less than 2 μm, the hardness and wear resistance are insufficient, and if it exceeds 5 μm, the wear resistance is insufficient.

(Example 2) Experiment No. 2-1 ... Similar to Experiment No. 1-1, a test piece of SKH51 high speed steel having a size of 17 × 17 × 2 mm and a Vickers hardness of Hv = 850 was used as a substrate. Electrolytic Ni plating was applied as one layer. One surface of the test piece was buffed to a mirror finish. Then, after electric field degreasing and washing with water to remove surface stains and improve water wetting, a temperature of 40 ° C. and a current density of 0.5 A in a solution containing 130 g / l of nickel sulfate and 15 g / l of boric acid. A Ni plating film was formed on the surface of the substrate by applying an electric field for 1 minute under the condition of / dm ² .

Next, in order to remove stains and oxides on the plated surface, buffing was performed to smooth the surface of the substrate, and then ultrasonic cleaning was performed in ethanol.

For the second layer and the third layer, a film was formed in the same manner as in Experiment No. 1-1 except that the film formation time was changed, and the same test as in Experiment No. 1-1 was conducted.

The thicknesses of the Ni-plated first layer, the Ti second layer and the third layer formed by ion plating of the formed film were measured by the ball crater method, and were 61 μm, 1.3 μm and 3.5 μm, respectively. there were. The Vickers hardness Hv (load: 50 g) of the film-forming surface of the substrate was 2200, which was a sufficient hardness, and the abrasion amount by the pin-on-disc abrasion test was 0.188 mm ³ , which was excellent abrasion resistance. Also, the adhesion between the plating layer and the second and third layers was good.

Next, the surface of the substrate on which the coating was formed was masked with an epoxy resin except for the surface on which the coating was formed, and a salt spray test (JI
As a result of S-Z-2371), no corroded portion was confirmed. The results are shown in Table 2.

Experiment Nos. 2-2 to 2-11 ... Electrolytic Ni plating was formed by the same method as Experiment No. 2-1, and after polishing the substrate surface, Ti, Zr, Hf, V, Nb, Ta or A Cr cathode was used to form a metal layer by changing the film formation time in the same manner as in Experiment No. 2-1, and then the film formation time was changed under nitrogen gas or acetylene gas or a mixed gas atmosphere thereof to form the third layer. Forming experiment number 2-1
The same test was performed. The results are shown in Table 2.

Experiment No. 2-2 The thickness of the first layer of the obtained coating was 75 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of the second layer of TiC was 2 μm, and the thickness of the third layer was 3.7 μm.
The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.182 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-3: The thickness of the first layer of the obtained coating was 66 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of TiC of the third layer was 1 μm and 3.2 μm.
The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.182 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-4: The thickness of the first layer of the obtained coating was 74 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrN of the fourth layer was 4 μm and the thickness of the third layer was 3.8 μm.
The Vickers hardness Hv was 1900, the wear amount in the wear test was 0.167 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-5 ... The thickness of the first layer of the obtained coating was 63 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrCN of the third layer was 7 μm, and the thickness was 4.0 μm. The Vickers hardness Hv was 2200, the wear amount in the wear test was 0.192 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-6 ... The thickness of the first layer of the obtained coating was 81 μm, and the thickness of the Hf layer of the second layer was 1.
The thickness of HfN of the first layer was 1 μm, and the thickness of the third layer was 4.5 μm.
The Vickers hardness Hv was 1900, the wear amount in the wear test was 0.201 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-7 The thickness of the first layer of the obtained coating was 55 μm, and the thickness of the second Hf layer was 1.
The thickness of HfCN of the third layer was 3 μm, and the thickness of HfCN was 4.3 μm. The Vickers hardness Hv was 2300, the wear amount in the wear test was 0.186 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-8: The thickness of the first layer of the obtained film was 62 μm, and the thickness of the V layer of the second layer was 1.2.
The thickness of the VN of the third layer was 3.8 μm. Vickers hardness Hv is 2000, wear amount in wear test is 0.1
At 94 mm ³ , no corroded part was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-9: The thickness of the first layer of the obtained coating was 71 μm, and the thickness of the Nb layer of the second layer was 1.
The thickness of NbN of the third layer was 4 μm, and the thickness of the third layer was 4.2 μm.
The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.195 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-10: The thickness of the first layer of the obtained film was 75 μm, the thickness of the Ta layer of the second layer was 1.3 μm, and the thickness of TaN of the third layer was 4.1 μm. It was The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.210 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-11 The thickness of the first layer of the obtained film was 64 μm, the thickness of the Cr layer of the second layer was 1.1 μm, and the thickness of CrN of the third layer was 4.4 μm. It was The Vickers hardness Hv was 2100, the wear amount in the wear test was 0.168 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment Nos. 2-12 to 18 ... A film was formed in the same manner as Experiment No. 2-1 except that the film forming time was changed, and the same test as Experiment No. 2-1 was conducted. The results are shown in Table 2.

Experiment No. 2-12 The thickness of the first layer of the obtained coating was 7 μm, and the thickness of the second Ti layer was 1.2 μm.
m, and the thickness of the third layer TiN was 4.3 μm. Vickers hardness Hv is 1900, wear amount in wear test is 0.1
As a result of performing a hydrochloric acid spray test at 26 mm ³ , a significantly corroded portion was observed. The hardness and wear resistance were sufficient, but the corrosion resistance was insufficient.

Experiment No. 2-13 The thickness of the first layer of the obtained film was 250 μm, and the thickness of the Ti layer of the second layer was 1.6.
μm, and the thickness of TiN of the third layer was 3.8 μm. The Vickers hardness Hv is 2200, and the wear amount in the wear test is 1.
At 558 mm ³ , no corroded part was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 2-14 The thickness of the first layer of the obtained coating was 77 μm, and an attempt was made to form TiN of the third layer without forming the second layer. Peeling occurred immediately after taking out. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was observed in the hydrochloric acid spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 2-15: The thickness of the first layer of the obtained coating was 77 μm, and the thickness of the second Ti layer was 0.4 μm.
m, the third layer of TiN peeled off immediately after being taken out from the ion plating apparatus. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was observed in the hydrochloric acid spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 2-16: The thickness of the first layer of the obtained coating was 82 μm, and the thickness of the second Ti layer was 8.3 μm.
m, and the thickness of the third layer TiN was 4.6 μm. Vickers hardness Hv is 2300, wear amount in wear test is 1.6
At 64 mm ³ , no corroded portion was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 2-17: The thickness of the first layer of the obtained coating was 67 μm, and the thickness of the second Ti layer was 1.3 μm.
m, and the thickness of the third layer TiN was 1.4 μm. Vickers hardness Hv is 700, wear amount in wear test is 1.77.
At 2 mm ³ , no corroded portion was observed in the hydrochloric acid spray test. The corrosion resistance was sufficient, but the hardness and wear resistance were insufficient.

Experiment No. 2-18 ... The thickness of the first layer of the obtained coating was 83 μm, and the thickness of the Ti layer of the second layer was 1.6 μm.
m, and the thickness of the third layer TiN was 7.2 μm. Vickers hardness Hv is 2400, wear amount in wear test is 2.1
At 02 mm ³ , no corroded part was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

The thickness of the first layer of electrolytic Ni plating is 10 μm
If it is less than 100 μm, the corrosion resistance becomes insufficient, and if it exceeds 100 μm, the abrasion resistance becomes insufficient. Further, when the second layer was not covered and when the thickness was less than 1 μm, peeling of the third layer occurred. If the thickness of the third layer is less than 2 μm, the hardness and wear resistance are insufficient, and if it exceeds 5 μm, the wear resistance is insufficient.

[0074]

Example 3 Experiment No. 3-1 ... Similar to Experiment No. 1-1, a test piece of SKH51 high speed steel having a size of 17 × 17 × 2 mm and a Vickers hardness of Hv = 850 was used as a substrate, and as a first layer. Electroless Ni-P plating was applied. One surface of the test piece was buffed to a mirror finish. Then, after electric field degreasing and washing with water to remove surface stains and improve water wetting, nickel chloride 30 g / l, sodium hypophosphite 10 g / l, sodium hydroxyacetate 50 g / l
Was dipped in a solution containing the above at a temperature of 90 ° C. for 2 hours to form a Ni—P plating film on the surface of the substrate. Then 3
Heat treatment was performed at 42 ° C. for 2 hours to precipitate Ni ₃ P and harden the surface.

Next, in order to remove stains and oxides on the plated surface, buffing was performed to smooth the substrate surface, and then ultrasonic cleaning was performed in ethanol.

For the second layer and the third layer, films were formed in the same manner as in Experiment No. 1-1 except for the film formation time, and the same tests as in Experiment No. 1-1 were conducted.

First of Ni-P plating of the formed film
The thicknesses of the layer, the second layer and the third layer of Ti formed by ion plating were measured by the ball crater method and were 55 μm, 1.1 μm and 3.5 μm, respectively. Vickers hardness Hv (load 50
The g9 had a sufficient hardness of 2100, and the wear amount by the pin-on-disk wear test was 0.205 mm ^3, showing excellent wear resistance. Also, the adhesion between the plating layer and the second and third layers was good.

Next, the surface of the substrate on which the film is formed is masked with an epoxy resin except for the surface on which the film is formed, and a salt spray test (JI
As a result of performing S-Z-2371), a corroded portion was not confirmed. The results are shown in Table 3.

Experiment Nos. 3-2 to 3-11 ... Electrolytic Ni plating was formed by the same method as Experiment No. 3-1, and after polishing the substrate surface, Ti, Zr, Hf, V, Nb, Ta or A Cr cathode was used to form a metal layer by changing the film forming time in the same manner as in Experiment No. 3-1, and then changing the film forming time under a nitrogen gas or acetylene gas or mixed gas atmosphere thereof to form the third layer. Forming experiment number 3-1
The same test was performed. The results are shown in Table 3.

Experiment No. 3-2 The thickness of the first layer of the obtained coating was 54 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of the second layer of TiC was 2 μm and the thickness of the third layer was 3.3 μm.
The Vickers hardness Hv was 2300, the wear amount in the wear test was 0.189 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-3 The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the second Ti layer was 1.
The thickness of TiCN of the third layer was 4 μm and was 3.7 μm. The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.203 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-4: The thickness of the first layer of the obtained coating film was 49 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of the second layer was 2 μm, and the thickness of ZrN of the third layer was 3.2 μm.
The Vickers hardness Hv was 2000, the wear amount in the wear test was 0.179 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-5 ... The thickness of the first layer of the obtained coating was 58 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrCN of the third layer was 2 μm, and the thickness of the third layer was 3.2 μm. The Vickers hardness Hv was 2200, the wear amount in the wear test was 0.187 mm ³ , and no corroded portion was recognized in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-6 ... The thickness of the first layer of the obtained film was 47 μm, and the thickness of the Hf layer of the second layer was 1.
The thickness of HfN of the third layer was 3 μm and the thickness of HfN was 4.5 μm.
The Vickers hardness Hv was 2300, the wear amount in the wear test was 0.155 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-7 The thickness of the first layer of the obtained coating was 56 μm, and the thickness of the Hf layer of the second layer was 1.
The thickness of HfCN of the third layer was 6 μm, and the thickness of HfCN was 4.3 μm. The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.199 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-8 ... The thickness of the first layer of the obtained coating film was 46 μm, and the thickness of the V layer of the second layer was 1.3.
The thickness of VN of the third layer was 3.7 μm. Vickers hardness Hv is 2000, wear amount in wear test is 0.2
At 11 mm ³ , no corroded part was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-9 The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the Nb layer of the second layer was 1.
The thickness of NbN of the second layer was 3.8 μm.
The Vickers hardness Hv was 2300, the wear amount in the wear test was 0.194 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-10 The thickness of the first layer of the obtained coating was 54 μm, the thickness of the Ta layer of the second layer was 1.3 μm, and the thickness of TaN of the third layer was 3.6 μm. It was The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.187 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-11: The thickness of the first layer of the obtained coating was 53 μm, the thickness of the Cr layer of the second layer was 1.5 μm, and the thickness of CrN of the third layer was 4.4 μm. It was The Vickers hardness Hv was 2200, the wear amount in the wear test was 0.169 mm ³ , and no corroded portion was observed in the hydrochloric acid spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment Nos. 3-12 to 18 ... A film was formed in the same manner as Experiment No. 3-1 except that the film formation time was changed, and the same test as Experiment No. 3-1 was conducted. The results are shown in Table 3.

Experiment No. 3-12 The thickness of the first layer of the obtained coating was 7 μm, and the thickness of the Ti layer of the second layer was 1.6 μm.
m, and the thickness of TiN of the third layer was 4.5 μm. Vickers hardness Hv is 1900, wear amount in wear test is 0.2
As a result of performing a hydrochloric acid spray test at 02 mm ³ , a significantly corroded portion was observed. The hardness and wear resistance were sufficient, but the corrosion resistance was insufficient.

Experiment No. 3-13 The thickness of the first layer of the obtained coating was 240 μm, and the thickness of the second Ti layer was 1.3.
μm, and the thickness of TiN of the third layer was 3.9 μm. The Vickers hardness Hv is 2200, and the wear amount in the wear test is 1.
At 665 mm ³ , no corroded part was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 3-14 The thickness of the first layer of the obtained coating was 67 μm, and an attempt was made to form TiN of the third layer without forming the second layer. Peeling occurred immediately after taking out. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was observed in the hydrochloric acid spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 3-15 The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the second Ti layer was 0.5 μm.
m, the third layer of TiN peeled off immediately after being taken out from the ion plating apparatus. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was observed in the hydrochloric acid spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 3-16 The thickness of the first layer of the obtained coating was 52 μm, and the thickness of the second Ti layer was 8.0 μm.
m, and the thickness of the third layer TiN was 4.3 μm. Vickers hardness Hv is 2400, wear amount in wear test is 1.6
At 68 mm ³ , no corroded portion was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 3-17 The thickness of the first layer of the obtained coating was 47 μm, and the thickness of the second Ti layer was 1.5 μm.
m, and the thickness of TiN of the third layer was 1.6 μm. Vickers hardness Hv is 900, wear amount in wear test is 1.98
At 2 mm ³ , no corroded portion was observed in the hydrochloric acid spray test. The corrosion resistance was sufficient, but the hardness and wear resistance were insufficient.

Experiment No. 3-18 The thickness of the first layer of the obtained coating was 53 μm, and the thickness of the second Ti layer was 1.4 μm.
m, and the thickness of TiN of the third layer was 8.2 μm. Vickers hardness Hv is 2500, wear amount in wear test is 2.5
At 59 mm ³ , no corroded part was observed in the hydrochloric acid spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

The thickness of the first layer of electroless Ni-P plating is 1
If it is less than 0 μm, the corrosion resistance becomes insufficient, and if it exceeds 100 μm, the abrasion resistance becomes insufficient. Further, when the second layer was not covered and when the thickness was less than 1 μm, peeling of the third layer occurred. If the thickness of the third layer is less than 2 μm, the hardness and wear resistance are insufficient, and if it exceeds 5 μm, the wear resistance is insufficient.

[0099]

Example 4 Experiment No. 4-1 A die of SKD11 die steel (Vickers hardness Hv = 850) was first subjected to hard Cr plating as the first layer. First, the mold is cleaned of the surface by electric field degreasing, etc., and after being wetted with water, chromic acid 3
A film was formed on the surface by applying an electric field for 1 minute in a solution containing 50 g / l, sulfuric acid 1 g / l and silicofluoric acid 16 g / l at a temperature of 35 ° C. and a current density of 5 A / dm ² .

Next, in order to remove stains and oxides on the plated surface, buffing was performed to smooth the surface of the mold, and then ultrasonic cleaning was performed in ethanol.

For the second layer and the third layer, a mold was set at a predetermined position in a cathodic arc type ion plating apparatus equipped with a Ti cathode, and then the reaction vessel was placed at 10 ⁻⁵ T.
After exhausting to orr, a bias voltage of 1000 V was applied to the substrate to cause arc discharge from the Ti cathode. The arc discharge current at this time was 60A. While monitoring the substrate surface temperature with an infrared radiation thermometer, arc discharge was continued for 2 minutes to vaporize and ionize Ti, and sputter cleaning of the substrate surface was performed. Up to 2 during arc discharge
A rise in the mold surface temperature was recognized up to 50 ° C.

Next, the bias voltage was lowered to 150 V, and a Ti layer as a second layer was formed on the substrate for 30 minutes.
Further, the voltage application to the Ti cathode was stopped, nitrogen gas was introduced into the reaction vessel, and the pressure in the vessel was 3 × 10 ^-2 Tor.
A bias voltage of 250 V was applied to the substrate while flowing nitrogen gas so as to maintain r, and arc discharge was generated from the Ti cathode. The arc discharge current at this time was 60A. The arc discharge continued for 1 hour. As a result, a third layer of TiN was further formed on the Ti layer.

Experiment No. 4-2 ... Experiment No. 4-1
In the above, only the hard Cr plating was applied to produce a hard Cr plated coating plastic mold.

Experiment No. 4-3 ... Experiment No. 4-1
In, a TiN-coated plastic mold was produced by directly depositing TiN without performing hard Cr plating.

Experiment No. 4-4 ... Experiment No. 4-1
Without coating the metal Ti layer after hard Cr plating in
A TiN film was directly formed to produce a TiN-coated plastic mold. When the surface of the mold after fabrication was observed, minute peeling was observed at the edge portion where stress was likely to concentrate.

Experiment No. 4-5 ... Experiment No. 4-1
~ 4-3 was used, and the mold of SKD11 without any surface treatment was used, and the flame retardant was added A
The BS resin was injection-molded at a temperature of 200 ° C. and a pressure of 1200 kg / cm ² , and the durability test of the mold was conducted. About 2000 ~ 3 for SKD11 mold without surface treatment
After 000 shots, a corroded part started to be observed on the mold surface,
Molding became impossible after 15,000 shots.

Also, in the case of the hard Cr-plated mold of Experiment No. 4-2, corrosion started at the cracked portion of the plating surface after a few thousand shots, and molding was impossible at 22,000 shots. Even with the TiN-treated mold of Experiment No. 4-3, it was confirmed that corrosion points were scattered on the coating after using several thousand shots, and the film began to peel off after 20,000 shots and after 22,000 shots. It became unusable.

On the other hand, the mold treated with the hard Cr plating of Experiment No. 4-1 and the coating of the three-layer structure of metallic Ti and TiN had no corrosion point during use and could be molded even after 200,000 shots. there were.

[0109]

According to the coating structure of the present invention, the first layer of plating improves the corrosion resistance of articles such as molds, machine parts and tools, and further Ti, Zr, Hf, V, Nb, Ta and Cr. At least one metal layer selected from
Lamination of at least one metal layer selected from Zr, Hf, V, Nb, Ta and Cr with a third layer made of carbide, nitride and / or carbonitride improves mechanical properties. The adhesion between the first layer and the third layer in the present invention is very good due to the presence of the metal layer which is the second layer, and it is an extremely effective corrosion / wear resistant coating having both corrosion resistance and mechanical properties. An attached article can be obtained.

[Table 1]

[Table 2]

[Table 3]

[Procedure amendment]

[Submission date] September 14, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

[Title of the Invention] Articles with a corrosion / wear resistant coating

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to articles such as plastic molding dies, tools and machine parts, and more particularly to articles having excellent wear resistance and corrosion resistance.

[0002]

2. Description of the Related Art As means for preventing abrasion of articles such as plastic molding dies, tools and machine parts, and extending their life,
A hard coating is formed on the surface of an article by a plating method, a PVD method, a CVD method, or the like. Here, as the hard coating, a Cr or Ni coating is formed by plating,
Ti, Zr, Hf, V, N by VD method or CVD method
Forming a coating layer made of at least one kind of carbide, nitride and / or carbonitride selected from b, Ta and Cr is performed.

Further, it is also practiced to form a two-layer film in which the above-mentioned plated film and a coating layer formed by a PVD method or a CVD method are combined. By forming these hard coatings, the wear resistance of the article is improved, and the life until the article is deteriorated is extended.

[0004]

However, since minute holes are present in the hard coating, corrosion of the article base material may progress from the holes in the molding of some plastics. It is considered that the cause of the corrosion is a corrosive gas such as HCl or SO _X which is generated when the plastic material is partially decomposed when the plastic is molded. This thermal decomposition of plastics and additives is remarkable especially when gas is mixed in the molten plastic fluid during injection molding, and it is considered that thermal decomposition of plastic is caused by local temperature rise due to adiabatic compression of the mixed gas. Has been. Typical resins that cause such mold corrosion include polyacetal, vinyl chloride resin, nylon resin and ABS resin (acrylonitrile, butadiene, styrene copolymer) and the like.

In the case of the plated coating, the hard Cr plating has innumerable cracks on the surface from the beginning, and although the wear resistance is improved, it is not effective against corrosion. Further, in Ni plating, the above-mentioned minute voids are eliminated by increasing the film thickness as a countermeasure against corrosion, but the hardness is insufficient, so that it is not possible to expect much effect on wear. There is.

Further, a two-layer film of a plating film and a PVD film or a CVD film is formed for the purpose of having both wear resistance and corrosion resistance. Although the corrosion resistance is improved as compared with the case where only the plating film is used, the corrosion resistance is less effective due to the cracks on the Cr plating surface. In the two-layer film with Ni plating, the thickness of the plating layer is increased to improve the corrosion resistance, but since the hardness is low, the improvement in wear resistance cannot be expected as much as in the case of hard Cr plating.

Further, in the case of a two-layer film with a plating film, PV
Depending on the film formation conditions of the D film or the CVD film, film peeling may occur and the wear resistance may be impaired. The cause of this is
Peeling may occur when the oxide film or stains generated during the plating treatment on the surface of the plating film cannot be sufficiently removed by the cleaning before the PVD treatment or the CVD treatment. Further, it is known that when the surface is polished for the purpose of removing the oxide film and dirt, the plating surface is distorted, which is released by the thermal history during the PVD treatment or the CVD treatment and causes peeling.

Further, articles used in an atmosphere in contact with corrosive gases and liquids are corroded by these corrosive substances. As a measure against corrosion, stainless steel metal, which is more resistant to corrosion, has been used as the material itself of the article, but in this case, the hardness of the article is insufficient and wear tends to occur. Therefore, improvement of the surface coating of articles such as molds for plastic molding, tools and machine parts, that is, development of articles having a coating excellent in abrasion resistance and corrosion resistance has been awaited.

[0009] Therefore, an object of the present invention is to solve the problems of the above-mentioned article having a hard abrasion-resistant hard coating, and to provide an article with a higher corrosion / wear-resistant coating.

[0010]

In order to achieve the above object, an article with a corrosion-resistant and abrasion-resistant hard coating of the present invention is provided with Cr or N formed by a plating method in close contact with the surface of the article.
a first layer made of i, and Ti, Zr, Hf, V, Nb and T coated on the first layer by an ion plating method.
a second layer made of at least one metal selected from a and at least one carbide, nitride and / or carbonitride selected from Ti, Zr, Hf, V, Nb and Ta in the second layer. It is characterized in that it has a third layer made of a material.

[0011]

The material of the article used in the present invention is a pure metal or an alloy material, and is particularly effective for a steel material such as die steel which is generally used in a mold. The article according to the present invention is not limited to plastic mold dies, tools, machine parts and the like, and can be used for a wide range of applications where abrasion resistance and corrosion resistance are required.

Any known plating method can be used to form the Cr or Ni layer of the present invention. Known PVD and CVD can be used for forming the second metal layer and the third hard coating of the present invention. The ion plating method, which is a kind of PVD, is also an advantageous method for forming the metal layer of the second layer, so that the hard coating of the third layer may be formed following the formation of the second layer by the ion plating method. But of course it doesn't matter.

Among the first layer coating methods used in the present invention, the plating method may be any known method, for example, the following method is used. The plating method for forming a hard Cr plating film is to remove the surface stains of the material by electric field degreasing, etc. and improve the water wetness, then chromic acid 350 g / l (liter), sulfuric acid 1 g / l, silicofluoric acid 16 g In a solution containing 1 / l, temperature 35 ° C, current density 5A
It is a method of forming a film on the surface by applying an electric field for 1 minute under the condition of / dm ² .

Among the methods for forming the Ni plating film, the electric field Ni plating method is performed at a temperature of 40 ° C. and a current density of 0 in a solution containing 130 g / l of nickel sulfate, 15 g / l of ammonium chloride and 15 g / l of boric acid. 1 under the condition of 0.5 A / dm ^2.
It is a method of forming a film on the surface by applying an electric field for a minute. Further, the electroless Ni-P plating is performed at a temperature of 9 in a solution containing 30 g / l of nickel chloride, 10 g / l of sodium hypophosphite, and 50 g / l of sodium hydroxyacetate.
This is a method of forming a film on the surface by immersing it for 2 hours under the condition of 0 ° C. After that, heat treatment is performed at 342 ° C. for 2 hours to precipitate Ni ₃ P and harden the surface.

The thickness of the plating film of the first layer is preferably 10 μm to 100 μm, and usually 30 μm to 70 μm.

After forming the plating film, buffing or the like is performed to remove surface stains and oxide film and to obtain smoothness to form the second and third layers.

In the ion plating method used for forming the second and third layers, generally, a metal is evaporated, the evaporated metal is ionized, and the ionized metal molecules are accelerated by an electric field in a reactive gas atmosphere. Then, it is attached and fixed to the surface of the article.

To vaporize the metal, either resistance heating or electron gun heating provided in a commercially available ion plating apparatus may be used. The vaporized metal may be ionized by any of known cathode arc discharge, glow discharge, high frequency discharge, a method using an ionization electrode, and a hollow cathode method. Among them, the cathodic arc discharge type ion plating method is a method in which metal evaporation and ionization are performed at the same time, and the metal ionization efficiency is higher than other methods, and the same metal source is used. Since it can be placed in the vacuum container, it is particularly preferable in the case of forming a film of a different kind of metal compound after forming the metal film as in the present invention.

When heating by ion irradiation is used when heating the substrate prior to forming the coating film, it is carried out by metal ions, and the electric field for accelerating the ionized metal ions is preferably 500V to 2000V as a voltage value. , And more preferably 800V to 1500V.

When forming the second layer of the metal coating, T
Using at least one metal selected from i, Zr, Hf, V, Nb, Ta and Cr as an evaporation source, evaporation of the metal,
Ionization may be performed under vacuum. The electric field for accelerating the ionized metal in forming the metal layer has a voltage value of 0V to 500V, preferably 0V to 200V. The thickness of the metal layer is preferably 0.5 μm to 2 μm,
Usually, it may be formed to a thickness of about 1 μm.

To prepare the hard coating of the third layer, Ti, Z
At least one metal selected from r, Hf, V, Nb, Ta and Cr is used as an evaporation source, and N is used as a reactive gas.
₂ , NH ₃ , hydrocarbons or organic compounds containing nitrogen, such as (CH ₃ ) ₃ N, can be used. The pressure of the reactive gas varies depending on the type of gas used, but generally it may be appropriately selected within the range of 10 ⁻³ to 10 ¹ Torr. The value of the voltage for accelerating the ionized metal when forming the hard coating of the third layer is preferably 50 V to 700 V, and more preferably 100 V to 500 V. The thickness of the hard coating of the third layer may be 2 to 5 μm.

In the present invention, the reason why the corrosion resistance is improved when the hard coating is a three-layer coating is presumed as follows. First, when the hard Cr plating is applied to the first layer, cracks occur on the plating surface. The base metal is corroded through the cracks. It is considered that when the second layer is coated with a metal layer by an ion plating method, the cracks are filled with the metal layer and the base metal is shielded from the atmosphere in which it is used, so that the corrosion resistance is improved. Further, if the hard coating of the third layer is directly coated on the polished first layer plating surface by the ion plating method, the strain remaining during polishing is released due to the thermal history during the treatment, which is harmful to the mechanical properties. Causes film peeling. However, when a metal layer is inserted as the second layer, it is considered that this layer acts as a buffer layer and prevents peeling.

Next, when electric field Ni plating or electroless Ni-P plating is applied to the first layer, similar to hard Cr plating,
Since the hard coating of the third layer is directly coated by the ion plating method for the polishing performed before coating the second layer,
Due to the thermal history during processing, the strain remaining during polishing is released, causing film peeling that is detrimental to mechanical properties. However, when a metal layer is inserted as the second layer, it is considered that this layer acts as a buffer layer and prevents peeling. In particular, in the case of electroless Ni-P plating that is heat-treated for hardening, the amount of strain accumulated in the plating film is large, and the relaxation effect due to the insertion of the metal layer is great.

[0024]

Example (Example 1) Experiment No. 1-1 ... Size 17 × 17 × 2 mm,
A test piece of SKH51 high speed steel with Vickers hardness Hv = 850 was used as a substrate, and hard Cr plating was applied as the first layer. One surface of the test piece was buffed to a mirror finish. Then, after electric field degreasing and washing with water to remove surface stains and improve water wetting, chromic acid 350 g /
A Cr plating film was formed on the substrate surface by applying an electric field for 1 minute in a solution containing 1 g of sulfuric acid, 1 g / l of sulfuric acid, and 16 g / l of silicofluoric acid at a temperature of 35 ° C. and a current density of 5 A / dm ² .

Next, in order to remove stains and oxides on the plated surface, buffing was performed to smooth the surface of the substrate, and then ultrasonic cleaning was performed in ethanol.

For the second layer and the third layer, the coating structure of the present invention was formed by using a cathodic arc type ion plating apparatus equipped with a Ti cathode. After setting the substrate at a predetermined position of the apparatus the reaction vessel, the reaction vessel 10 ^-5
Exhausted to Torr.

Next, a bias voltage of 1000 V was applied to the substrate to cause arc discharge from the Ti cathode. The arc discharge current at this time was 60A. While monitoring the substrate surface temperature with an infrared radiation thermometer, arc discharge was continued for 5 minutes to vaporize and ionize Ti, and the substrate surface was sputter cleaned. Maximum 450 ° C during arc discharge
Up to the substrate surface temperature was observed. Further, the bias voltage was lowered to 150 V, and a Ti layer as a second layer was formed on the substrate for 30 minutes.

Next, the voltage application to the Ti cathode was stopped, nitrogen gas was introduced into the reaction vessel, and the pressure inside the vessel was reduced to 3
A bias voltage of 300 V was applied to the substrate while flowing a nitrogen gas so as to maintain × 10 ⁻² Torr to cause arc discharge from the Ti cathode. The arc discharge current at this time was 80A. The arc discharge continued for 1 hour. As a result, a third layer of TiN was further formed on the Ti layer.

The thicknesses of the Cr-plated first layer, the Ti second layer and the third layer formed by ion plating of the formed film were measured by the ball crater method and found to be 35 μm, 1.2 μm and 3.2 μm, respectively. there were. The Vickers hardness Hv (load: 50 g) of the film-forming surface of the substrate was 2100, which was a sufficient hardness, and the wear amount by the pin-on-disk wear test was 0.179 mm ³ , which was excellent wear resistance. Also, the adhesion between the plating layer and the second and third layers was good. Hardness is Vickers hardness Hv (load 50g) of 1500 to 2000 or more, and wear resistance is 1 mm by a pin-on-disk wear test.
^{A value of 3} or less is sufficient.

Next, the surface of the substrate on which the coating is formed is masked with an epoxy resin except for the surface on which the coating is formed, and a salt spray test (JI
As a result of S-Z-2371), no corroded portion was confirmed. The results are shown in Table 1.

Experiment Nos. 1-2 to 1-11 ... Hard Cr plating was formed by the same method as Experiment No. 1-1, and after polishing the substrate surface, Ti, Zr, Hf, V, Nb, Ta or A Cr cathode was used to form a metal layer by changing the film forming time in the same manner as in Experiment No. 1-1, and then changing the film forming time in a nitrogen gas or acetylene gas or mixed gas atmosphere thereof to form the third layer. Forming experiment number 1-1
The same test was performed. The results are shown in Table 1.

Experiment No. 1-2 ... The thickness of the first layer of the obtained coating was 40 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of TiC of the third layer was 4 μm and was 3.5 μm.
The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.187 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-3: The thickness of the first layer of the obtained coating was 42 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of TiCN of the third layer was 5 μm and was 3.6 μm. The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.201 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-4 ... The thickness of the first layer of the obtained coating was 43 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrN of the third layer was 3 μm and the thickness of ZrN was 3.7 μm.
The Vickers hardness Hv was 1900, the wear amount in the wear test was 0.212 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-5 ... The thickness of the first layer of the obtained coating was 38 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrCN of the third layer was 5 μm, and the thickness of the third layer was 4.1 μm. The Vickers hardness Hv was 2200, the wear amount in the wear test was 0.178 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-6 ... The thickness of the first layer of the obtained coating was 44 μm, and the thickness of the second Hf layer was 1.
The thickness of HfN of the second layer was 2 μm and the thickness of the third layer was 3.5 μm.
The Vickers hardness Hv was 2000, the wear amount in the wear test was 0.188 mm ³ , and no corroded portion was observed in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-7 ... The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the Hf layer of the second layer was 1.
The thickness of HfCN of the third layer was 4 μm, and the thickness of HfCN was 3.3 μm. The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.210 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-8 ... The thickness of the first layer of the obtained coating was 35 μm, and the thickness of the V layer of the second layer was 1.1.
The thickness of the VN of the third layer was 3.2 μm. Vickers hardness Hv is 1800, wear amount in wear test is 0.1
At 95 mm ³ , no corroded part was observed in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-9: The thickness of the first layer of the obtained coating was 42 μm, and the thickness of the Nb layer of the second layer was 1.
The thickness of NbN of the third layer was 3 μm, and the thickness thereof was 4.8 μm.
The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.185 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-10: The thickness of the first layer of the obtained film was 44 μm, the thickness of the Ta layer of the second layer was 1.7 μm, and the thickness of TaN of the third layer was 4.6 μm. It was The Vickers hardness Hv was 2600, the wear amount in the wear test was 0.178 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 1-11: The thickness of the first layer of the obtained coating was 44 μm, the thickness of the Cr layer of the second layer was 1.7 μm, and the thickness of CrN of the third layer was 3.4 μm. It was The Vickers hardness Hv was 1900, the wear amount in the wear test was 0.152 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment Nos. 1-12 to 18 ... Films were formed in the same manner as in Experiment No. 1-1 by changing only the film forming time, and the same tests as in Experiment No. 1-1 were conducted. The results are shown in Table 1.

Experiment No. 1-12 The thickness of the first layer of the obtained coating was 6 μm, and the thickness of the second Ti layer was 1.5 μm.
m, and the thickness of the third layer TiN was 4.2 μm. Vickers hardness Hv is 1700, wear amount in wear test is 0.1
As a result of conducting a salt spray test at 79 mm ³ , a significantly corroded portion was observed. The hardness and wear resistance were sufficient, but the corrosion resistance was insufficient.

Experiment No. 1-13 ... The thickness of the first layer of the obtained coating was 230 μm, and the thickness of the second Ti layer was 1.6.
The thickness of the third layer of TiN was 3.7 μm. The Vickers hardness Hv is 2100, and the wear amount in the wear test is 1.
At 242 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 1-14 The thickness of the first layer of the obtained coating was 57 μm, and an attempt was made to form TiN of the third layer without forming the second layer. Peeling occurred immediately after taking out. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was found in the salt spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 1-15 The thickness of the first layer of the obtained coating was 57 μm, and the TiN of the second layer was peeled off immediately after being taken out from the ion plating apparatus. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was found in the salt spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 1-16 The thickness of the first layer of the obtained coating was 57 μm, and the thickness of the second Ti layer was 7.3 μm.
m, and the thickness of TiN of the third layer was 4.1 μm. Vickers hardness Hv is 2200, wear amount in wear test is 1.3
At 86 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 1-17 The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the second Ti layer was 1.4 μm.
m, and the thickness of TiN of the third layer was 1.3 μm. Vickers hardness Hv is 800, wear amount in wear test is 1.67
At 2 mm ³ , no corroded part was observed in the salt spray test. The corrosion resistance was sufficient, but the hardness and wear resistance were insufficient.

Experiment No. 1-18: The thickness of the first layer of the obtained film was 59 μm, and the thickness of the second Ti layer was 1.2 μm.
m, and the thickness of TiN of the third layer was 9.5 μm. Vickers hardness Hv is 2200, wear amount in wear test is 1.5
At 67 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient. The thickness of the first layer of hard Cr plating is 10 μm
If it is less than 100 μm, the corrosion resistance becomes insufficient, and if it exceeds 100 μm, the abrasion resistance becomes insufficient. Further, when the second layer was not covered and when the thickness was less than 1 μm, peeling of the third layer occurred. If the thickness of the third layer is less than 2 μm, the hardness and wear resistance are insufficient, and if it exceeds 5 μm, the wear resistance is insufficient.

Example 2 Experiment No. 2-1 ... Similar to Experiment No. 1-1, a test piece of SKH51 high speed steel having a size of 17 × 17 × 2 mm and a Vickers hardness of Hv = 850 was used as a substrate. Electrolytic Ni plating was applied as one layer. One surface of the test piece was buffed to a mirror finish. Then, after electric field degreasing and washing with water to remove surface stains and improve water wetting, a temperature of 40 ° C. and a current density of 0.5 A in a solution containing 130 g / l of nickel sulfate and 15 g / l of boric acid. A Ni plating film was formed on the substrate surface by applying an electric field for 1 minute under the condition of / dm ² .

Next, in order to remove stains and oxides on the plated surface, buffing was performed to smooth the surface of the substrate, and then ultrasonic cleaning was performed in ethanol.

For the second layer and the third layer, films were formed in the same manner as in Experiment No. 1-1 except for the film formation time, and the same tests as in Experiment No. 1-1 were conducted.

The thicknesses of the Ni-plated first layer, the ion-plated Ti second layer, and the third layer of the formed film were measured by the ball crater method, and were 61 μm, 1.3 μm, and 3.5 μm, respectively. there were. The Vickers hardness Hv (load: 50 g) of the film formation surface of the substrate was 2200, which was a sufficient hardness, and the wear amount by the pin-on-disk wear test was 0.188 mm ³ , which was excellent wear resistance. Also, the adhesion between the plating layer and the second and third layers was good.

Next, the surface of the substrate on which the coating was formed was masked with an epoxy resin except for the surface on which the coating was formed, and the salt spray test (JI
As a result of S-Z-2371), no corroded portion was confirmed. The results are shown in Table 2.

Experiment Nos. 2-2 to 2-11 ... Electrolytic Ni plating was formed by the same method as Experiment No. 2-1, and after polishing the substrate surface, Ti, Zr, Hf, V, Nb, Ta or A Cr cathode was used to form a metal layer by changing the film formation time in the same manner as in Experiment No. 2-1, and then the film formation time was changed under nitrogen gas or acetylene gas or a mixed gas atmosphere thereof to form the third layer. Forming experiment number 2-1
The same test was performed. The results are shown in Table 2.

Experiment No. 2-2: The thickness of the first layer of the obtained coating was 75 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of the second layer of TiC was 2 μm, and the thickness of the third layer was 3.7 μm.
The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.182 mm ³ , and no corroded portion was observed in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-3 ... The thickness of the first layer of the obtained coating was 66 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of TiC of the third layer was 1 μm and 3.2 μm.
The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.182 mm ³ , and no corroded portion was observed in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-4: The thickness of the first layer of the obtained coating was 74 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrN of the fourth layer was 4 μm and the thickness of the third layer was 3.8 μm.
The Vickers hardness Hv was 1900, the wear amount in the wear test was 0.167 mm ³ , and no corroded portion was observed in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-5 ... The thickness of the first layer of the obtained coating was 63 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrCN of the third layer was 7 μm, and the thickness was 4.0 μm. The Vickers hardness Hv was 2200, the wear amount in the wear test was 0.192 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-6 ... The thickness of the first layer of the obtained film was 81 μm, and the thickness of the Hf layer of the second layer was 1.
The thickness of HfN of the first layer was 1 μm, and the thickness of the third layer was 4.5 μm.
The Vickers hardness Hv was 1900, the wear amount in the wear test was 0.201 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-7 ... The thickness of the first layer of the obtained coating was 55 μm, and the thickness of the Hf layer of the second layer was 1.
The thickness of HfCN of the third layer was 3 μm, and the thickness of HfCN was 4.3 μm. The Vickers hardness Hv was 2300, the wear amount in the wear test was 0.186 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-8 The thickness of the first layer of the obtained coating was 62 μm, and the thickness of the V layer of the second layer was 1.2.
The thickness of the VN of the third layer was 3.8 μm. Vickers hardness Hv is 2000, wear amount in wear test is 0.1
At 94 mm ³ , no corroded part was observed in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-9 ... The thickness of the first layer of the obtained coating was 71 μm, and the thickness of the Nb layer of the second layer was 1.
The thickness of NbN of the third layer was 4 μm, and the thickness of the third layer was 4.2 μm.
The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.195 mm ³ , and no corroded portion was found in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-10: The thickness of the first layer of the obtained coating was 75 μm, the thickness of the Ta layer of the second layer was 1.3 μm, and the thickness of TaN of the third layer was 4.1 μm. It was The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.210 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 2-11: The thickness of the first layer of the obtained coating film was 64 μm, the thickness of the Cr layer of the second layer was 1.1 μm, and the thickness of CrN of the third layer was 4.4 μm. It was The Vickers hardness Hv was 2100, the wear amount in the wear test was 0.168 mm ³ , and no corroded portion was observed in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment Nos. 2-12 to 18 ... A film was formed in the same manner as Experiment No. 2-1 except that the film forming time was changed, and the same test as Experiment No. 2-1 was conducted. The results are shown in Table 2.

Experiment No. 2-12 The thickness of the first layer of the obtained coating was 7 μm, and the thickness of the second Ti layer was 1.2 μm.
m, and the thickness of the third layer TiN was 4.3 μm. Vickers hardness Hv is 1900, wear amount in wear test is 0.1
As a result of performing a salt spray test at 26 mm ³ , a significantly corroded portion was observed. The hardness and wear resistance were sufficient, but the corrosion resistance was insufficient.

Experiment No. 2-13 The thickness of the first layer of the obtained coating film was 250 μm, and the thickness of the second Ti layer was 1.6.
μm, and the thickness of TiN of the third layer was 3.8 μm. The Vickers hardness Hv is 2200, and the wear amount in the wear test is 1.
At 558 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 2-14: The thickness of the first layer of the obtained film was 77 μm, and an attempt was made to form TiN of the third layer without forming the second layer. Peeling occurred immediately after taking out. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was found in the salt spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 2-15: The thickness of the first layer of the obtained film was 77 μm, and the thickness of the second Ti layer was 0.4 μm.
m, the third layer of TiN peeled off immediately after being taken out from the ion plating apparatus. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was found in the salt spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were both insufficient.

Experiment No. 2-16: The thickness of the first layer of the obtained coating was 82 μm, and the thickness of the second Ti layer was 8.3 μm.
m, and the thickness of the third layer TiN was 4.6 μm. Vickers hardness Hv is 2300, wear amount in wear test is 1.6
At 64 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 2-17 The thickness of the first layer of the obtained coating was 67 μm, and the thickness of the second Ti layer was 1.3 μm.
m, and the thickness of the third layer TiN was 1.4 μm. Vickers hardness Hv is 700, wear amount in wear test is 1.77.
At 2 mm ³ , no corroded part was observed in the salt spray test. The corrosion resistance was sufficient, but the hardness and wear resistance were insufficient.

Experiment No. 2-18 ... The thickness of the first layer of the obtained coating was 83 μm, and the thickness of the second Ti layer was 1.6 μm.
m, and the thickness of the third layer TiN was 7.2 μm. Vickers hardness Hv is 2400, wear amount in wear test is 2.1
At 02 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

The thickness of the first layer of electrolytic Ni plating is 10 μm
If it is less than 100 μm, the corrosion resistance becomes insufficient, and if it exceeds 100 μm, the abrasion resistance becomes insufficient. Further, when the second layer was not covered and when the thickness was less than 1 μm, peeling of the third layer occurred. If the thickness of the third layer is less than 2 μm, the hardness and wear resistance are insufficient, and if it exceeds 5 μm, the wear resistance is insufficient.

[0075]

Example 3 Experiment No. 3-1 ... Similar to Experiment No. 1-1, a test piece of SKH51 high speed steel having a size of 17 × 17 × 2 mm and a Vickers hardness of Hv = 850 was used as a substrate, and as a first layer. Electroless Ni-P plating was applied. One surface of the test piece was buffed to a mirror finish. Then, after electric field degreasing and washing with water to remove surface stains and improve water wetting, nickel chloride 30 g / l, sodium hypophosphite 10 g / l, sodium hydroxyacetate 50 g / l
And a Ni-P plating film was formed on the surface of the substrate by immersing the solution in a solution containing the above at a temperature of 90 ° C. for 2 hours. Then 3
Subjected to heat treatment for 2 hours at 42 ° C, to cure the surface to precipitate Ni 3 _P.

Next, in order to remove stains and oxides on the plated surface, buffing was performed to smooth the surface of the substrate, and then ultrasonic cleaning was performed in ethanol.

For the second layer and the third layer, coatings were formed in the same manner as in Experiment No. 1-1 except for the film formation time, and the same tests as in Experiment No. 1-1 were conducted.

First of Ni-P plating of formed film
The thicknesses of the layer, the second layer and the third layer of Ti formed by ion plating were measured by the ball crater method and were 55 μm, 1.1 μm and 3.5 μm, respectively. Vickers hardness Hv (load 50
g) had a sufficient hardness of 2100, and the amount of abrasion by the pin-on-disc abrasion test was 0.205 mm ^3, showing excellent abrasion resistance. Also, the adhesion between the plating layer and the second and third layers was good.

Next, the surface of the substrate on which the coating is formed is masked with an epoxy resin except for the surface on which the coating is formed, and a salt spray test (JI
As a result of performing S-Z-2371), a corroded portion was not confirmed. The results are shown in Table 3.

Experiment Nos. 3-2 to 3-11 ... Electroless Ni-P plating was formed by the same method as Experiment No. 3-1, and after polishing the surface of the substrate, Ti, Zr, Hf, V, Nb. ,
A Ta or Cr cathode was used to form a metal layer by changing the film formation time in the same manner as in Experiment No. 3-1, and then the film formation time was changed under a nitrogen gas or acetylene gas or mixed gas atmosphere thereof. Three layers were formed and the same test as Experiment No. 3-1 was performed. The results are shown in Table 3.

Experiment No. 3-2 The thickness of the first layer of the obtained coating was 54 μm, and the thickness of the Ti layer of the second layer was 1.
The thickness of the second layer of TiC was 2 μm and the thickness of the third layer was 3.3 μm.
The Vickers hardness Hv was 2300, the wear amount in the wear test was 0.189 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-3 The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the second Ti layer was 1.
The thickness of TiCN of the third layer was 4 μm and was 3.7 μm. The Vickers hardness Hv was 2400, the wear amount in the wear test was 0.203 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-4 The thickness of the first layer of the obtained coating was 49 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of the second layer was 2 μm, and the thickness of ZrN of the third layer was 3.2 μm.
The Vickers hardness Hv was 2000, the wear amount in the wear test was 0.179 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-5 ... The thickness of the first layer of the obtained coating was 58 μm, and the thickness of the Zr layer of the second layer was 1.
The thickness of ZrCN of the third layer was 2 μm, and the thickness of the third layer was 3.2 μm. The Vickers hardness Hv was 2200, the wear amount in the wear test was 0.187 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-6 ... The thickness of the first layer of the obtained coating was 47 μm, and the thickness of the second Hf layer was 1.
The thickness of HfN of the third layer was 3 μm and the thickness of HfN was 4.5 μm.
The Vickers hardness Hv was 2300, the wear amount in the wear test was 0.155 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-7 ... The thickness of the first layer of the obtained coating was 56 μm, and the thickness of the Hf layer of the second layer was 1.
The thickness of HfCN of the third layer was 6 μm, and the thickness of HfCN was 4.3 μm. The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.199 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-8 ... The thickness of the first layer of the obtained coating was 46 μm, and the thickness of the V layer of the second layer was 1.3.
The thickness of VN of the third layer was 3.7 μm. Vickers hardness Hv is 2000, wear amount in wear test is 0.2
At 11 mm ³ , no corroded part was observed in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-9: The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the Nb layer of the second layer was 1.
The thickness of NbN of the second layer was 3.8 μm.
The Vickers hardness Hv was 2300, the wear amount in the wear test was 0.194 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-10 ... The thickness of the first layer of the obtained coating was 54 μm, the thickness of the Ta layer of the second layer was 1.3 μm, and the thickness of TaN of the third layer was 3.6 μm. It was The Vickers hardness Hv was 2500, the wear amount in the wear test was 0.187 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment No. 3-11 The thickness of the first layer of the obtained coating was 53 μm, the thickness of the Cr layer of the second layer was 1.5 μm, and the thickness of CrN of the third layer was 4.4 μm. It was The Vickers hardness Hv was 2200, the wear amount in the wear test was 0.169 mm ³ , and no corroded portion was recognized in the salt spray test. The hardness, wear resistance and corrosion resistance were all sufficient.

Experiment Nos. 3-12 to 18 ... A film was formed by the same method as Experiment No. 3-1 except that the film forming time was changed, and the same test as Experiment No. 3-1 was conducted. The results are shown in Table 3.

Experiment No. 3-12 The thickness of the first layer of the obtained coating was 7 μm, and the thickness of the second Ti layer was 1.6 μm.
m, and the thickness of TiN of the third layer was 4.5 μm. Vickers hardness Hv is 1900, wear amount in wear test is 0.2
As a result of conducting a salt spray test at 02 mm ³ , a significantly corroded portion was observed. The hardness and wear resistance were sufficient, but the corrosion resistance was insufficient.

Experiment No. 3-13 The thickness of the first layer of the obtained coating was 240 μm, and the thickness of the second Ti layer was 1.3 μm.
μm, and the thickness of TiN of the third layer was 3.9 μm. The Vickers hardness Hv is 2200, and the wear amount in the wear test is 1.
At 665 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 3-14 The thickness of the first layer of the obtained coating was 67 μm, and an attempt was made to form TiN of the third layer without forming the second layer. Peeling occurred immediately after taking out. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was found in the salt spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 3-15 The thickness of the first layer of the obtained coating was 48 μm, and the thickness of the second Ti layer was 0.5 μm.
m, the third layer of TiN peeled off immediately after being taken out from the ion plating apparatus. Therefore, the Vickers hardness Hv and the abrasion test could not be measured. However, no corroded part was found in the salt spray test. Corrosion resistance can be secured by the plating layer, but hardness and wear resistance were insufficient.

Experiment No. 3-16: The thickness of the first layer of the obtained coating was 52 μm, and the thickness of the second Ti layer was 8.0 μm.
m, and the thickness of the third layer TiN was 4.3 μm. Vickers hardness Hv is 2400, wear amount in wear test is 1.6
At 68 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

Experiment No. 3-17 The thickness of the first layer of the obtained coating was 47 μm, and the thickness of the second Ti layer was 1.5 μm.
m, and the thickness of TiN of the third layer was 1.6 μm. Vickers hardness Hv is 900, wear amount in wear test is 1.98
At 2 mm ³ , no corroded part was observed in the salt spray test. The corrosion resistance was sufficient, but the hardness and wear resistance were insufficient.

Experiment No. 3-18 The thickness of the first layer of the obtained coating was 53 μm, and the thickness of the second Ti layer was 1.4 μm.
m, and the thickness of TiN of the third layer was 8.2 μm. Vickers hardness Hv is 2500, wear amount in wear test is 2.5
At 59 mm ³ , no corroded part was observed in the salt spray test. Hardness and corrosion resistance were sufficient, but wear resistance was insufficient.

The thickness of the first layer of electroless Ni-P plating is 1
If it is less than 0 μm, the corrosion resistance becomes insufficient, and if it exceeds 100 μm, the abrasion resistance becomes insufficient. Further, when the second layer was not covered and when the thickness was less than 1 μm, peeling of the third layer occurred. If the thickness of the third layer is less than 2 μm, the hardness and wear resistance are insufficient, and if it exceeds 5 μm, the wear resistance is insufficient.

[0100]

Example 4 Experiment No. 4-1 A die of SKD11 die steel (Vickers hardness Hv = 850) was first subjected to hard Cr plating as the first layer. After removing the dirt from the surface of the mold by electric field degreasing and improving the wettability with water, chromic acid 3
A film was formed on the surface by applying an electric field for 1 minute in a solution containing 50 g / l, sulfuric acid 1 g / l, and silicofluoric acid 16 g / l at a temperature of 35 ° C. and a current density of 5 A / dm ² .

Next, in order to remove stains and oxides on the plated surface, buffing was performed to smooth the surface of the mold, and then ultrasonic cleaning was performed in ethanol.

For the second layer and the third layer, a mold was set at a predetermined position in a cathodic arc type ion plating apparatus equipped with a Ti cathode, and then a reaction vessel was placed at 10 ^-5.
After exhausting to Torr, a bias voltage of 1000 V was applied to the substrate to cause arc discharge from the Ti cathode. The arc discharge current at this time was 60A. While monitoring the substrate surface temperature with an infrared radiation thermometer, arc discharge was continued for 2 minutes to vaporize and ionize Ti, and sputter cleaning of the substrate surface was performed. Up to 2 during arc discharge
A rise in the mold surface temperature was recognized up to 50 ° C.

Next, the bias voltage was lowered to 150 V, and a Ti layer as a second layer was formed on the substrate for 30 minutes.
Further, the voltage application to the Ti cathode was stopped, nitrogen gas was introduced into the reaction vessel, and the pressure inside the vessel was 3 × 10 ⁻² To.
250V to the substrate while flowing nitrogen gas to keep rr
Was applied to cause arc discharge from the Ti cathode. The arc discharge current at this time was 60A. The arc discharge continued for 1 hour. As a result, a third layer of TiN was further formed on the Ti layer.

Experiment No. 4-2 ... Experiment No. 4-1
In the above, only the hard Cr plating was applied to produce a hard Cr plated coating plastic mold.

Experiment No. 4-3 ... Experiment No. 4-1
In, a TiN-coated plastic mold was produced by directly depositing TiN without performing hard Cr plating.

Experiment No. 4-4 ... Experiment No. 4-1
Without coating the metal Ti layer after hard Cr plating in
A TiN film was directly formed to produce a TiN-coated plastic mold. When the surface of the die after fabrication was observed, minute peeling was observed at the essence portion where stress was likely to concentrate.

Experiment No. 4-5 ... Experiment No. 4-1
~ 4-3 was used, and the mold of SKD11 without any surface treatment was used, and the flame retardant was added A
The BS resin was injection-molded at a temperature of 200 ° C. and a pressure of 1200 kg / cm ² , and the durability test of the mold was conducted. About 2000 ~ 3 for SKD11 mold without surface treatment
After 000 shots, a corroded part started to be observed on the mold surface,
Molding became impossible after 15,000 shots.

In the mold of Experiment No. 4-2 which was plated with hard Cr, corrosion started at the cracks on the plating surface after a few thousand shots, and molding was impossible at 22,000 shots. Even with the TiN-treated mold of Experiment No. 4-3, it was confirmed that corrosion points were scattered on the coating after using several thousand shots, and the film began to peel off after 20,000 shots and after 22,000 shots. It became unusable.

On the other hand, the die treated with the hard Cr plating of Experiment No. 4-1 and the coating of the three-layer structure of metallic Ti and TiN has no corrosion point during use, and can be molded even after 200,000 shots. there were.

[00110]

According to the coating structure of the present invention, the first layer of plating improves the corrosion resistance of articles such as molds, machine parts and tools, and further Ti, Zr, Hf, V, Nb, Ta and Cr. At least one metal layer selected from
Lamination of at least one metal layer selected from Zr, Hf, V, Nb, Ta and Cr with a third layer made of carbide, nitride and / or carbonitride improves mechanical properties. The adhesion between the first layer and the third layer in the present invention is very good due to the presence of the metal layer which is the second layer, and it is an extremely effective corrosion / wear resistant coating having both corrosion resistance and mechanical properties. An attached article can be obtained.

[Table 1]

[Table 2]

[Table 3]

Claims (4)

[Claims] 1. A first layer of Cr or Ni formed by a plating method so as to be in close contact with the surface of an article, and Ti, Zr, H coated on the first layer by an ion plating method.
A second layer made of at least one metal selected from f, V, Nb, Ta and Cr, and T on the second layer.
A corrosion- and wear-resistant coating having a third layer made of a carbide, nitride and / or carbonitride of at least one metal selected from i, Zr, Hf, V, Nb, Ta and Cr. With goods. 2. The thickness of the Cr or Ni layer of the first layer is 10
The article with a corrosion / wear resistant coating according to claim 1, wherein the article has a thickness of from 100 to 100 µm. 3. The article with a corrosion / wear resistant coating according to claim 1, wherein the second layer has a thickness of 0.5 μm to 2 μm. 4. The article with a corrosion / wear resistant coating according to claim 1, 2 or 3, wherein the thickness of the third layer is 2 μm to 5 μm.