JPH06346239A - Production of ceramic coated metallic material - Google Patents

Abstract

PURPOSE:To produce a ceramic coated metallic material having high hardness and excellent in corrosion resistance as well as wear resistance. CONSTITUTION:A metallic substrate is coated with at least one ceramic layer of nitride, carbide or carbonitride of a group IV, VI or VIII metal of the periodic table such as Ti by physical vapor deposition such as ion plating or chemical vapor deposition and nitrogen-contg. gas such as nitrogen, carbon-contg. gas such as acetylene or a mixture of them is excited with plasma and brought into contact with the surface of the ceramic layer to obtain the objective ceramic coated metallic material useful as a cutlery, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic-coated metal material, for example, an electric machine, a transportation machine, a machine tool, a precision machine, a civil construction machine and their parts; tools; building materials; furniture materials; The present invention relates to a method for producing a metal material, such as tableware, kitchen knives, scissors, etc .; ornaments; all other metal materials, which are ceramic-coated for the purpose of imparting high hardness, wear resistance, corrosion resistance, and the like.

[0002]

2. Description of the Related Art A metal material coated with ceramics for the purpose of imparting high hardness, wear resistance, corrosion resistance and the like is known. For example, knives such as kitchen knives, scissors, and knives have conventionally been made of carbon steel or stainless steel,
Carbon steel is prone to rust, and stainless steel, which has high corrosion resistance, has a problem that the blade edge is soft and the blade edge wears down after repeated use, resulting in reduced sharpness. To improve this, typified by TiN and TiC. In recent years, active research and development have been carried out on coating metal nitriding and carbide ceramics on a blade substrate by physical vapor deposition or chemical vapor deposition. For example, JP-A-1-47849 proposes a method of forming TiN on a blade substrate by physical vapor deposition such as ion plating or sputtering, and then coating metal nitride such as CrN or TiCN or carbonitride ceramics. Thus, a ceramic-coated metal material having high hardness, wear resistance, corrosion resistance, etc. has been obtained. However, in these ceramic coatings, pitting corrosion is likely to occur from the grain boundaries of the crystals forming the coating, and the corrosion resistance remains a problem.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above drawbacks, and an object thereof is to solve the drawbacks of conventional ceramics-coated metal materials, including the conventional ceramics-coated blades described above. It is an object of the present invention to provide a method for producing a ceramic-coated metal material that has high hardness and wear resistance as well as excellent corrosion resistance.

[0004]

The metal substrate used in the present invention is not particularly limited as long as it is a metal. For example, steel such as stainless steel or carbon steel; silicon, aluminum, titanium, molybdenum. And pure metals such as tungsten and alloys thereof. The shape is not particularly limited, and examples thereof include a plate shape, a linear shape, and a tubular shape.

In the method for producing a ceramic-coated metal material according to the present invention, first, the periodic table 4, 6, 8, 13 or 1 is formed on the metal substrate by physical vapor deposition or chemical vapor deposition.
At least one ceramic layer made of a Group 4 metal nitride, carbide, or carbonitride is coated.

Examples of the physical vapor deposition method include vacuum vapor deposition, ion plating and sputtering. Examples of the chemical vapor deposition method include plasma CV
Method D is mentioned. In the present invention, the surface of the ceramic layer is treated with plasma after the coating of the ceramic layer. Therefore, among the above vapor deposition methods, ion plating, sputtering and plasma CVD methods which are methods utilizing plasma are preferable.

Periodic table 4, 6, 8, 13 or 1
Examples of the Group 4 metal include Group 4 titanium, zirconium, and hafnium; Group 6 chromium, molybdenum, and tungsten; Group 8 iron; Group 13 aluminum; Group 14 silicon. In order to coat a metal substrate with a ceramic layer made of a nitride, a carbide, or a carbonitride of the metal, the metal itself is used as a raw material in ion plating or sputtering, and a plasma CV is used.
In the method D, a metal compound gas such as a hydride, a halide or an alcoholate of the metal is used as a raw material.

A known method for coating the above metal substrate with a ceramic layer made of a nitride, a carbide or a carbonitride of the metal by a physical vapor deposition method or a chemical vapor deposition method using these raw materials. You can follow.

For example, by ion plating,
In order to coat the ceramics layer, the raw material metal is vaporized, the vaporized particles are further ionized, and the ionized metal is coated with a nitrogen-containing gas, for example, when coating a nitride,
Gases such as nitrogen and ammonia; carbon-containing gases when coating carbides, for example, alkane gases such as methane, ethane, propane, butane, pentane, hexane, etc., alkene gases such as ethylene, propylene, butene, pentene, etc. , Pentadiene, butadiene and other alkadiene gases, acetylene, methylacetylene and other alkyne gases, benzene, toluene, xylene, indene, naphthalene, phenanthrene and other aromatic hydrocarbon gases, cyclopropane, cyclohexane and other cyclones Gases such as alkane-based gases, cycloalkene-based gases such as cyclopentene, cyclohexene, etc .; when carbonitride is coated, it is reacted with a mixed gas of the above-mentioned carbon-containing gas and nitrogen-containing gas.

The above-mentioned ion plating method is not particularly limited, and a conventionally known method can be used. Examples thereof include an arc discharge method, a high frequency excitation method, and a hollow cathode discharge method. The difference between these methods is that the metal evaporation method and the evaporation particle ionization method are different.

As a specific procedure for coating the ceramics layer by ion plating, the water-cooled crucible containing the raw metal and the vacuum container containing the metal substrate are evacuated to 1 × 10 ^-5 Torr or less. Then, the raw material metal is vaporized by melting and heating and the like, and an ionization means (for example, in the case of the arc discharge method, an ionization electrode is used, and the ionization current at that time is adjusted to an ionization current of 20 A to 80 A). The vaporized particles are ionized by. At the same time, the total pressure in the vacuum container of the nitrogen-containing gas, the carbon-containing gas or the mixed gas is 4 ×.
It is introduced into a vacuum container so that the pressure becomes 10 ^{−4 to} 3 × 10 ⁻³ Torr. After that, a DC voltage of −1000 to −25 V is applied to the metal substrate that has been heated to a temperature of 200 to 800 ° C. in advance, and the ionized metal and the above-mentioned nitrogen-containing gas, carbon-containing gas or a mixed gas thereof are added. The metal nitride, carbide or carbonitride obtained by the reaction is vapor-deposited on the metal substrate to form the desired ceramic layer.

In order to coat the ceramics layer by sputtering, a nitrogen-containing gas is used when a metal nitride is formed in a discharge argon gas, and a carbon-containing gas is used when a carbide is formed in the argon gas for discharge. When forming a gas or carbonitride, a reactive gas consisting of a mixed gas of a carbon-containing gas and a nitrogen-containing gas is mixed. In this state, sputtering is performed, and the atoms from the target are reacted with the reactive gas on the heated metal substrate to form the respective metal compounds. Examples of the above carbon-containing gas and nitrogen-containing gas are the same as those used in the above-mentioned ion plating.

In order to coat the ceramic layer by the plasma CVD method, a metal compound gas such as a hydride, a halide or an alcoholate of the above metal, and a nitrogen-containing gas or a carbide when forming a metal nitride. In the case of forming a carbon-containing gas, in the case of forming a carbonitride, a metal substrate is placed in a source gas composed of a mixed gas of a carbon-containing gas and a nitrogen-containing gas, and a DC or high-frequency power is applied to the source gas near the metal substrate. Then, the raw material gas is turned into plasma.
This causes a chemical reaction to form a reaction product metal nitride, metal carbide or metal carbonitride on the metal substrate. Examples of the above carbon-containing gas and nitrogen-containing gas are the same as those used in the above-mentioned ion plating.

In the method for producing a ceramic-coated metal material according to the present invention, next, a nitrogen-containing gas, a carbon-containing gas or a mixed gas thereof is excited by plasma and brought into contact with the surface of the ceramic layer.

Examples of the nitrogen-containing gas include gases such as nitrogen and ammonia. Further, hydrogen gas or a rare gas such as argon, helium, neon, or xenon may be added to the nitrogen-containing gas. For example, in the case where the titanium nitride layer is subjected to the above treatment, if hydrogen gas is added to nitrogen gas so that the concentration of hydrogen gas in the total gas is 10 to 30% by volume, NH _x ( _X is 1 to 3) in plasma. Since the number of excited species is generated, the processed thickness of the titanium nitride layer is increased by about 1.5 times as compared with the case where only the nitrogen gas is processed. Further, when a rare gas is added to nitrogen gas so that the concentration of the rare gas in all the gases is 10 to 99% by volume, the plasma density is increased by the addition of the rare gas and the excited decomposition of the nitrogen gas is promoted. The processed thickness of the layer increases. In this case, when argon and helium are used as the rare gas and the volume ratio of argon and helium is about 80:20, the effect is particularly remarkable. Further, when hydrogen gas and rare gas are used together, this effect is further enhanced.

As the carbon-containing gas, for example, methane,
Alkane-based gases such as ethane, propane, butane, pentane and hexane, alkenes-based gases such as ethylene, propylene, butene and pentene, alkadiene-based gases such as pentadiene and butadiene, alkyne-based gases such as acetylene and methylacetylene , Benzene, toluene, xylene, indene, naphthalene, phenanthrene, and other aromatic hydrocarbon gases, cyclopropane, cyclohexane, and other cycloalkane gases, cyclopentene, cyclohexene, and other cycloalkene gases, and the like.
These gases may be used alone or in combination of two or more. Further, hydrogen gas or a rare gas such as argon, helium, neon, or xenon may be added to the carbon-containing gas. Two or more rare gases may be mixed. For example, in the case where the titanium carbide layer is subjected to the above treatment, if hydrogen gas is added to the carbon-containing gas so that the concentration of hydrogen gas in all gases is 10 to 30% by volume, CH _x (in plasma) (
_{Since X} is an excited species of 1 to 4), the treated thickness of the titanium carbide layer is about 1.5 times larger than when treated with only the carbon-containing gas. Further, by adding a rare gas to the carbon-containing gas, the concentration of the rare gas in all the gases is set to 10-9.
When it is 9% by volume, the plasma density is increased by adding the rare gas, and the excited decomposition of the carbon-containing gas is promoted.
The processed thickness of the titanium carbide layer increases. in this case,
When argon and helium are used as the rare gas and the volume ratio of argon and helium is about 80:20, the effect is particularly remarkable. Further, when hydrogen gas and rare gas are used together, this effect is further enhanced.

As the mixed gas of the nitrogen-containing gas and the carbon-containing gas, there may be mentioned a gas in which one or more kinds of the above-mentioned nitrogen-containing gas and carbon-containing gas are mixed. Furthermore, when a rare gas is mixed with this mixed gas, the thickness of the ceramic layer to be processed becomes large. The mixing ratio of the nitrogen-containing gas and the carbon-containing gas varies depending on the desired ceramic composition that will be formed on the surface layer of the ceramic layer by the plasma treatment. For example, when the ceramic layer is made of titanium carbide and the titanium carbonitride is to be formed by plasma treatment, the mixing ratio of the nitrogen-containing gas and the carbon-containing gas is not 1: 1 but the ratio of the nitrogen-containing gas is higher. To do. Similarly, when the ceramic layer is made of titanium nitride and the titanium carbonitride is to be formed by plasma treatment, the mixture ratio of the nitrogen-containing gas and the carbon-containing gas is not 1: 1 but the ratio of the carbon-containing gas is more Make it higher This optimum ratio depends on the gas type and must be determined appropriately.

In the present invention, whether the ceramic layer is a metal nitride, a carbide or a carbonitride,
The type of gas to be brought into contact with plasma excitation is a nitrogen-containing gas,
Any gas may be used as long as it is a carbon-containing gas or a mixed gas thereof.

Excitation means include, for example, a method of plasma decomposition by applying a direct current or a high frequency, a method of plasma decomposition by microwave discharge, a method of plasma decomposition by electron cyclotron resonance, and a method of thermal decomposition by heating with a hot filament. Etc. In this case, in order to simplify the process, it is preferable to use the plasma means of the same method as the plasma means used for forming the ceramic layer.

The optimum conditions for the plasma treatment differ depending on the excitation means. The procedure for the case of plasma decomposition by applying the above DC power is shown below. First, the vacuum container is evacuated to 1 × 10 ⁻⁵ Torr or less. Then, a gas such as a nitrogen-containing gas or a carbon-containing gas used for the treatment is introduced, and the pressure is 0.01 to 1 Torr.
Adjust to r. After that, 200-800 ℃ in advance
To the substrate to be treated that has been heated at the temperature of -2000-
Applying a DC voltage of 25V to turn the above gas into plasma,
Process for about 10 to 60 minutes. If the treatment time is too short, the layer to be treated becomes thin and the effect is weakened, and if it is too long, the ceramic layer of the substrate to be treated is damaged and the quality of the ceramic layer deteriorates.

According to the manufacturing method of the present invention, the corrosion resistance of the ceramic layer is improved. The reason for this is considered as follows. For example, when the titanium nitride layer is brought into contact with a plasma-excited product of a nitrogen-containing gas, nitrogen is diffused from the surface according to conditions such as a processing gas, a processing time and a processing temperature, and nitridation of unreacted titanium proceeds, so that the layer A denser and stronger titanium nitride layer with a different titanium to nitrogen ratio is formed.
Further, when the titanium nitride layer is brought into contact with a plasma excitation product of a carbon-containing gas, carbon is similarly diffused and carbonized from the surface according to the conditions, and a titanium carbonitride layer is formed on the surface layer.
A ceramic material having extremely high scratch resistance and hardness can be obtained. When the titanium carbonitride layer produced in this case is compared with the conventional titanium carbonitride coating, the conventional titanium carbonitride coating has a low surface hardness, but the coating of the present invention is superior to the titanium nitride coating which is a high hardness material. Since the titanium carbonitride coating is formed on the surface, it is considered that both hardness and scratch resistance are large.

The thickness of the ceramic layer treated in the plasma step by the method for producing a ceramic-coated metal material of the present invention is appropriately determined depending on the application, but is 0.05 μm.
m or more is preferable. However, even if the optimum processing condition is selected, it is difficult to process deeply to a thickness of 2 μm or more.

In the present invention, in order to improve the adhesion with the ceramic layer, the metal substrate may be added as necessary.
Before forming the ceramics layer, the surface of the substrate on which the ceramics layer is formed may be washed with an organic solvent and subjected to a bombarding treatment under a reduced pressure with an inert gas such as Ar or a metal ion such as Ti.

Further, in the present invention, in order to improve the adhesion between the metal substrate and the ceramic layer, a metal layer made of only the above metal is physically or chemically vapor-deposited between the metal substrate and the ceramic layer. It may be provided by law. The metal layer works to relieve the stress of the ceramic layer, thereby improving the adhesion. The thickness of the metal layer varies depending on the composition of the metal substrate or the ceramic layer, but is preferably in the range of 0.1 to 1 μm. If the thickness is too large or too small, the stress balance is lost, and the ceramic film is likely to peel off.

When this metal layer is provided by, for example, ion plating, first, the vacuum container containing the water-cooled crucible containing the metal of the vapor deposition material to be formed and the substrate is evacuated to 1 × 10 ^-5 Torr or less. Then, the vapor deposition material metal is vaporized by melting and heating, and the vaporized particles of the metal are ionized by an ionization means (for example, an ionization electrode). The total pressure in the vacuum container at this time is 1 x
The ^{pressure is set} to 10 ⁻⁵ to 4 × 10 ⁻⁵ Torr. After that, 20
-1 on a metal substrate that has been heated to a temperature of 0 to 800 ° C
A DC voltage of 000 to -25V is applied to vaporize the ionized metal vaporized particles on the substrate to form a metal layer.

The second aspect of the present invention is a ceramic layer made of a nitride, a carbide or a carbonitride of a metal of Group 4, 6, 8, 13 or 14 of the periodic table by the physical vapor deposition method or the chemical vapor deposition method of the present invention. At least one layer, and a nitrogen-containing gas, a carbon-containing gas, or a mixed gas thereof is excited by plasma and brought into contact with the surface of the ceramic layer.
Instead of the above, “a metal layer made of a metal of Group 4, 6, 8, 13 or 14 of the periodic table is coated by a physical vapor deposition method or a chemical vapor deposition method, and then the surface of the metal layer is covered with a nitrogen-containing gas or carbon. A gas containing or a mixed gas thereof is excited by plasma and brought into contact with each other to form a ceramic layer made of a nitride, a carbide or a carbonitride of the metal on the surface layer portion of the metal layer, and further, a physical layer is formed on the ceramic layer. A ceramics layer made of the same elemental species as the ceramics layer by a chemical vapor deposition method or a chemical vapor deposition method. "

In the second aspect of the present invention, first, periodic tables 4, 6 and 6 are formed on a metal substrate by physical vapor deposition or chemical vapor deposition.
A metal layer consisting of a Group 8, 13 or 14 metal is coated.

The metals of Groups 4, 6, 8, 13 or 14 of the Periodic Table are the same as those used in the present invention. Examples of the physical vapor deposition method include vacuum vapor deposition, ion plating, and sputtering. Examples of the chemical vapor deposition method include a plasma CVD method.
In the present invention, the surface of the metal layer is treated with plasma after coating with the metal layer. Therefore, among the above vapor deposition methods, ion plating, sputtering and plasma CVD methods, which are methods utilizing plasma, are preferable.

In ion plating and sputtering, the metal itself is used as a raw material, and in the plasma CVD method, a metal compound gas such as a hydride, a halide or an alcoholate of the metal is used as a raw material.

A known method may be used to coat the metal layer on the above-mentioned metal substrate by the physical vapor deposition method or the chemical vapor deposition method using these raw materials.

For example, by ion plating,
In order to coat the metal layer, first, the water-cooled crucible containing the metal of the vapor deposition material to be formed and the vacuum container containing the substrate are evacuated to 1 × 10 ⁻⁵ Torr or less. Then, the vapor deposition material metal is vaporized by melting and heating, and the vaporized particles of the metal are ionized by an ionization means (for example, an ionization electrode). The total pressure in the vacuum container at this time is 1 x 1
It is set to 0 ⁻⁵ to 4 × 10 ⁻⁵ Torr. Then 200 in advance
-10 on a metal substrate that has been heated to a temperature of ~ 800 ° C.
A direct current voltage of 00 to -25V is applied to vaporize the ionized metal vaporized particles on the substrate to form a metal film.

In order to coat the metal layer by sputtering, the above source metal is used as a target and placed in an argon gas for discharge. Sputter in this state,
The same metal layer as the target is formed on the heated metal substrate.

In order to coat a metal layer by the plasma CVD method, a metal substrate is placed in a source gas composed of a metal compound gas such as a hydride, a halide or an alcoholate of the above metal, and the source gas in the vicinity of the metal substrate is treated. Direct-current or high-frequency power is applied to turn the source gas into plasma. This causes a chemical reaction to form a metal on the metal substrate.

The thickness of the metal layer varies depending on the type of metal and the type of ceramic layer to be coated in a later step,
The range of 0.1 to 3 μm is preferable. If the thickness is too large or too small, the stress balance is lost, and the ceramic film is likely to peel off.

In the second aspect of the present invention, after coating the metal layer, a nitrogen-containing gas, a carbon-containing gas or a mixed gas thereof is excited by plasma and brought into contact with the surface of the metal layer, and the surface layer of the metal layer is covered with the metal. Forming a ceramic layer of the nitride, carbide or carbonitride.

Examples of nitrogen-containing gas include gases such as nitrogen and ammonia. Further, hydrogen gas or a rare gas such as argon, helium, neon, or xenon may be added to the nitrogen-containing gas. For example, in the case of nitriding a titanium layer, if hydrogen gas is added to nitrogen gas so that the concentration of hydrogen gas in all gases is 10 to 30% by volume, NH in plasma
_{Since X} ( _X is a number of 1 to 3) excited species are generated, the nitride layer is formed to be about 1.5 times thicker than the case where only nitrogen gas is used for treatment. Further, when a rare gas is added to nitrogen gas so that the concentration of the rare gas in the total gas is 10 to 99% by volume, the plasma density is increased by the addition of the rare gas and the excited decomposition of the nitrogen gas is promoted, so that the nitride layer Becomes thicker. In this case, when argon and helium are used as the rare gas and the volume ratio of argon and helium is about 80:20, the effect is particularly remarkable. Further, when hydrogen gas and rare gas are used together, this effect is further enhanced.

Examples of the carbon-containing gas include methane,
Alkane-based gases such as ethane, propane, butane, pentane and hexane, alkenes-based gases such as ethylene, propylene, butene and pentene, alkadiene-based gases such as pentadiene and butadiene, alkyne-based gases such as acetylene and methylacetylene , Benzene, toluene, xylene, indene, naphthalene, phenanthrene, and other aromatic hydrocarbon gases, cyclopropane, cyclohexane, and other cycloalkane gases, cyclopentene, cyclohexene, and other cycloalkene gases, and the like.
These gases may be used alone or in combination of two or more. Further, hydrogen gas or a rare gas such as argon, helium, neon, or xenon may be added to the carbon-containing gas. Two or more rare gases may be mixed. For example, when carbonizing the titanium layer, hydrogen gas is added to the carbon-containing gas to adjust the hydrogen gas concentration in the total gas to 10 to 3
When it is 0% by volume, CH _X ( _X is a number of 1 to 4) excited species are generated in the plasma, so that titanium carbide is formed to be about 1.5 times thicker than the case where only carbon-containing gas is treated. To be done. Further, when the rare gas is added to the carbon-containing gas to make the concentration of the rare gas in all gases 10 to 99% by volume, the plasma density is increased by the addition of the rare gas and the excited decomposition of the carbon-containing gas is promoted. The titanium carbide layer becomes thicker. In this case, when argon and helium are used as the rare gas and the volume ratio of argon and helium is about 80:20,
The effect is particularly remarkable. Further, when hydrogen gas and rare gas are used together, this effect is further enhanced.

As the mixed gas of the nitrogen-containing gas and the carbon-containing gas, there may be mentioned a gas in which one or more kinds of each of the nitrogen-containing gas and the carbon-containing gas are mixed. Further, when the rare gas is mixed with this mixed gas, the processing layer becomes thick.
The mixing ratio of the nitrogen-containing gas and the carbon-containing gas is preferably the same as the composition of the ceramic layer to be produced, and this ratio differs depending on the gas species and needs to be appropriately determined.

Excitation means include, for example, a method of plasma decomposition by applying a direct current or a high frequency, a method of plasma decomposition by microwave discharge, a method of plasma decomposition by electron cyclotron resonance, and a method of thermal decomposition by heating with a hot filament. Etc. In this case, in order to simplify the process, it is preferable to use the same plasma means as that used for forming the metal layer.

The optimum conditions for the plasma treatment differ depending on the means of excitation. The procedure for the case of plasma decomposition by applying the above DC power is shown below. First, the vacuum container is evacuated to 1 × 10 ⁻⁵ Torr or less. Then, a gas such as a nitrogen-containing gas or a carbon-containing gas used for the treatment is introduced, and the pressure is 0.01 to 1 Tor.
Adjust to r. After that, 200-800 ℃ in advance
To the substrate to be treated that has been heated at the temperature of -2000-
Applying a DC voltage of 25V to turn the above gas into plasma,
Process for about 10 to 60 minutes. If the treatment time is too short, the layer to be treated becomes thin and the effect becomes weak. If the treatment time is too long, the metal layer of the substrate to be treated is damaged and the quality of the ceramic layer deteriorates.

According to the manufacturing method of the present invention 2, when the surface layer portion of the metal layer is treated with a nitrogen-containing gas, a nitride of the metal,
When treated with a carbon-containing gas, a ceramic layer made of a carbide of the metal, and when treated with a mixed gas thereof, a ceramic layer made of a carbonitride of the metal is formed. If the thickness of this ceramic layer is too thin, the effect of improving the adhesiveness with the ceramic layer to be coated on this layer will be weakened.
It is preferably at least μm.

According to the second aspect of the present invention, a ceramic layer made of a nitride, a carbide or a carbonitride of the metal is formed on the surface layer of the metal layer, and then a physical vapor deposition method or a chemical vapor deposition method is applied on the ceramic layer. And covering a ceramics layer made of the same elemental species as the ceramics layer.

Examples of the physical vapor deposition method include vacuum vapor deposition, ion plating and sputtering. Examples of the chemical vapor deposition method include plasma CV
Method D is mentioned. In view of productivity, the same method as that used for coating the metal layer is preferable.

Examples of the metal used in this method include titanium, zirconium and hafnium of group 4; chromium, molybdenum, tungsten of group 6; iron of group 8; aluminum of group 13; silicon of group 14 and the like. . In order to coat a metal substrate with a ceramic layer made of a nitride, a carbide, or a carbonitride of the metal, the metal itself is used as a raw material in ion plating or sputtering, and the metal is used in a plasma CVD method. The metal compound gas such as hydride, halide, or alcoholate is used as a raw material.

A known method can be used for coating the above-mentioned ceramic layer using these raw materials by a physical vapor deposition method or a chemical vapor deposition method with a ceramic layer made of a nitride, a carbide or a carbonitride of the metal. You can follow.

For example, by ion plating,
To coat the ceramics layer, the raw material metal is vaporized, and the vaporized particles are ionized, and the ionized metal is nitrogen-containing gas when coating a nitride, carbon-containing gas when coating a carbide, carbonization When coating with a nitride, it is reacted with a mixed gas of the above-mentioned carbon-containing gas and nitrogen-containing gas. Examples of the above-mentioned carbon-containing gas and nitrogen-containing gas are the same as those used for forming a ceramic layer made of a nitride, a carbide or a carbonitride of the metal on the surface layer portion of the metal layer. .

The above-mentioned ion plating method is not particularly limited, and a conventionally known method can be used. Examples thereof include arc discharge method, high frequency excitation method and hollow cathode discharge method.

As a concrete procedure for coating the ceramics layer by ion plating, a water-cooled crucible containing a raw material metal and a vacuum container accommodating the ceramics-treated metal substrate are set to 1 × 10 ^-5 Torr or less. Exhaust to. Then, the raw material metal is vaporized by melting and heating and the like, and an ionization means (for example, in the case of the arc discharge method, an ionization electrode is used, and the ionization current at that time is adjusted to an ionization current of 20 A to 80 A). The vaporized particles are ionized by. At the same time, the above nitrogen-containing gas, carbon-containing gas or mixed gas thereof is added to the vacuum vessel at a total pressure of 4 × 10 ^{−4 to} 3 × 10 ^−3.
It is introduced into a vacuum container so that it becomes Torr. afterwards,
A direct current voltage of -1000 to -25V is applied to the above-mentioned metal substrate which has been heated to a temperature of 200 to 800 ° C in advance,
Targeted ceramics by vapor-depositing metal nitrides, carbides or carbonitrides obtained by reacting an ionized metal with the above-mentioned nitrogen-containing gas, carbon-containing gas or a mixed gas thereof. Form the layers.

In order to coat the ceramics layer by sputtering, a nitrogen-containing gas is used in the case of forming a metal nitride and a carbon-containing gas is used in the case of forming a carbide in a discharge argon gas, using the above-mentioned raw material metal as a target. When forming a gas or carbonitride, a reactive gas consisting of a mixed gas of a carbon-containing gas and a nitrogen-containing gas is mixed. In this state, sputtering is performed, and the atoms from the target are reacted with the reactive gas on the heated metal substrate to form the respective metal compounds. Examples of the above carbon-containing gas and nitrogen-containing gas are the same as those used in the above-mentioned ion plating.

In order to coat the ceramic layer by the plasma CVD method, a metal compound gas such as a hydride, a halide or an alcoholate of the above metal, and a nitrogen containing gas or a carbide when forming a metal nitride. In the case of forming a carbon-containing gas, in the case of forming a carbonitride, in the raw material gas consisting of a mixed gas of a carbon-containing gas and a nitrogen-containing gas, the metal base is placed, and a direct current or a direct current is supplied to the raw material gas near the metal base. High-frequency power is applied to turn the source gas into plasma. This causes a chemical reaction to form a reaction product metal nitride, metal carbide or metal carbonitride on the metal substrate. Examples of the above carbon-containing gas and nitrogen-containing gas are the same as those used in the above-mentioned ion plating.

The thickness of the ceramic layer is 0.
It is preferably 5 μm to 7 μm. The larger the thickness, the easier the peeling, and the smaller the thickness, the weaker the hardness.

According to the second aspect of the present invention, it is possible to obtain a ceramic-coated metal material in which high hardness, wear resistance, and corrosion resistance are imparted to the metal substrate, and the adhesion between the metal substrate and the ceramic layer is particularly excellent. The reason for this is considered as follows.
It has been conventionally done to provide a metal intermediate layer between the metal substrate and the ceramic layer in order to improve the adhesion between the metal substrate and the ceramic layer, but in this case, the metal intermediate layer and the ceramic layer are provided. There are clear interfaces between the layers. On the other hand, in the present invention, since the surface layer portion of the metal intermediate layer is modified into the ceramic layer by the plasma, there is no clear interface with the ceramic layer formed thereon. Therefore, in the present invention, it is considered that the adhesiveness during this period is improved. Further, since the metal base and the metal layer are metals, the adhesion is good. Therefore, the present invention provides
It is considered that the adhesion between the metal substrate and the ceramic layer is improved.

The reason why the corrosion resistance is improved is that the ceramic layer formed by the plasma treatment is extremely fine crystals, and the ceramic layer formed thereon has a crystal diameter smaller than that of the conventional product, reflecting the properties of the base. It is thought that it is getting smaller.

[0054]

EXAMPLES Examples will be shown below to specifically explain the present invention. Examples 1 to 8 and Comparative Examples 1 to 3 are examples and comparative examples of the present invention, and Examples 9 to 16 are examples of the present invention 2. In each of the examples and comparative examples, high vacuum arc discharge type ion plating apparatus (manufactured by Shinko Seiki Co., Ltd., model: AI-850SE) was used to perform coating and plasma treatment under required film forming conditions. . Further, the thickness of the metal coating and the ceramic coating was measured by a fluorescent X-ray microscopic film thickness meter (manufactured by Seiko Denshi Kogyo KK, model: SFT-157).

Example 1 (a) 50 made of high-speed steel (SS51) as a metal substrate
A flat plate of × 50 × 3 mm was used, and ultrasonic cleaning was performed using acetone to remove oil on the surface. This metal substrate and titanium as a vapor deposition material are placed in a vacuum container, and the inside of the container is
After evacuating to a pressure of × 10 ^-5 Torr or less, the metal substrate is heated to 500 ° C, and titanium is evaporated while applying a voltage of -500V to the metal substrate to 4 × 10 ^-5 Torr.
Under the conditions, the titanium coating was vapor-deposited by ion plating until the thickness of the titanium coating became 0.5 μm. Thus, the metal layer was formed.

(B) Next, the heating temperature of the metal substrate is set to 50.
While maintaining the temperature at 0 ° C. and applying a voltage of −500 V to the metal substrate, titanium was vaporized and nitrogen gas was introduced as a reaction gas so that the total pressure was 7 × 10 ⁻⁴ Torr, and the titanium nitride film was coated with 3%. The same film was vapor-deposited by ion plating until the thickness became 0.0 μm. (C) Next, the evaporation of titanium is stopped, the heating temperature of the metal substrate is maintained at 500 ° C., and nitrogen gas is introduced at 200 sccm while applying a voltage of −1000 V to the metal substrate,
Plasma treatment was performed for 30 minutes under the condition of 0.1 Torr.
Thus, a ceramics-coated metal material was manufactured.

Example 2 In step (c) of Example 1, nitrogen gas was added at 200 sc.
A ceramic-coated metal material was produced in the same manner as in Example 1 except that nitrogen gas of 160 sccm and hydrogen gas of 40 sccm were introduced instead of introducing cm. Example 3 In the step (c) of Example 1, 200 sc of nitrogen gas was used.
A ceramic-coated metal material was produced in the same manner as in Example 1 except that nitrogen gas of 80 sccm, hydrogen gas of 20 sccm, argon gas of 50 sccm, and helium gas of 50 sccm were introduced instead of introducing cm. Example 4 In the step (c) of Example 1, 200 sc of nitrogen gas was used.
cm, instead of introducing acetylene gas 160 sccm
A ceramic-coated metal material was produced in the same manner as in Example 1 except that argon gas of 40 sccm was introduced, and the heating temperature of the metal substrate was 700 ° C. instead of 500 ° C.

Example 5 In step (b) of Example 1, acetylene gas was used as the reaction gas instead of nitrogen gas, and -7 was added to the metal substrate.
While applying a voltage of 50 V, titanium was vaporized and the acetylene gas was introduced so that the total pressure was 8 × 10 ⁻⁴ Torr, and the same was applied by ion plating until the titanium carbide film became 3.0 μm thick. A ceramic-coated metal material was produced in the same manner as in Example 1 except that a film was deposited and that acetylene gas was introduced at 200 sccm instead of introducing 200 sccm in step (c) of Example 1. did.

Example 6 In the step (c) of Example 5, acetylene gas was added to 20
Instead of introducing 0 sccm, nitrogen gas is added at 200 sccc
A ceramic-coated metal material was produced in the same manner as in Example 5, except that m was introduced. Example 7 In the step (b) of Example 1, nitrogen gas and acetylene gas were used as the reaction gas instead of nitrogen gas in a flow rate ratio of 3: 7.
In the step (c) of Example 1, the nitrogen carbonitride film was vapor-deposited by ion plating until the titanium carbonitride film had a thickness of 3.0 μm. Gas 60s
A ceramic-coated metal material was produced in the same manner as in Example 1 except that csc and acetylene gas were introduced at 140 sccm.

Example 8 (a) Stainless steel (SUS304) as a metal substrate
Using a flat plate of 50 × 50 × 2 mm manufactured by Mfg. Co., Ltd., ultrasonic cleaning was performed with acetone to remove oil on the surface. This metal substrate and chromium as a vapor deposition material are placed in a vacuum container, the interior of the container is evacuated to 1 × 10 ⁻⁵ Torr or less, and then the metal substrate is heated to 500 ° C.
While applying a voltage of V, chromium is evaporated and 4 × 10
^The chromium coating was deposited by ion plating until the thickness of the chromium coating became 0.5 μm under the condition of ⁻⁵ Torr.
Thus, the metal layer was formed.

(B) Next, the heating temperature of the metal substrate is set to 50.
While maintaining the temperature at 0 ° C. and applying a voltage of −750 V to the metal substrate, chromium was vaporized and acetylene gas was introduced as a reaction gas so that the total pressure was 6 × 10 ⁻⁴ Torr, and the chromium carbide film was formed to 3 The same film was vapor-deposited by ion plating until the thickness became 0.0 μm. (C) Next, the evaporation of chromium is stopped, the heating temperature of the metal substrate is maintained at 500 ° C., acetylene gas is introduced at 200 sccm while applying a voltage of −1000 V to the metal substrate, and the temperature is set to 30 at 0.1 Torr. Minute plasma treatment was performed. Thus, a ceramics-coated metal material was manufactured.

Comparative Example 1 A ceramic-coated metal material was produced in the same manner as in Example 1 except that the step (c) of Example 1 was not performed. Comparative Example 2 A ceramic-coated metal material was produced in the same manner as in Example 6 except that the step (c) of Example 6 was not performed. Comparative Example 3 A ceramic-coated metal material was produced in the same manner as in Example 7, except that the step (c) of Example 7 was not performed.

Example 9 (a) 50 made of high-speed steel (SS51) as a metal substrate
A flat plate of × 50 × 3 mm was used, and ultrasonic cleaning was performed using acetone to remove oil on the surface. Place this metal substrate and titanium as a vapor deposition material in a vacuum container, and
After evacuating to a pressure of × 10 ^-5 Torr or less, the metal substrate is heated to 500 ° C, and titanium is evaporated while applying a voltage of -500V to the metal substrate to 4 × 10 ^-5 Torr.
Under the conditions, the titanium coating was vapor-deposited by ion plating until the thickness of the titanium coating became 0.5 μm. Thus, the metal layer was formed. (B) Next, the evaporation of titanium is stopped, the heating temperature of the metal substrate is maintained at 500 ° C., and while applying a voltage of −1000 V to the metal substrate, 200 sccm of nitrogen gas is introduced,
Plasma treatment was performed for 30 minutes under the condition of 0.1 Torr. (C) Next, while maintaining the heating temperature of the metal substrate at 500 ° C. and applying a voltage of −500 V to the metal substrate, titanium is vaporized and the total pressure of nitrogen gas as a reaction gas is 7 × 10 ⁻⁴ Torr. And the titanium nitride film was deposited by ion plating until the titanium nitride film had a thickness of 3.0 μm to produce a ceramic-coated metal material. In addition, when the above steps (a) and (b) were separately performed and the production was stopped, and the metal layer of the obtained metal substrate was observed, it had a golden color and surface analysis by X-ray electron spectroscopy. As a result, it was found that a titanium nitride layer having a thickness of 0.2 μm was formed.

Example 10 In the step (b) of Example 9, 200 sc of nitrogen gas was used.
A ceramic-coated metal material was manufactured in the same manner as in Example 9 except that 160 sccm of nitrogen gas and 40 sccm of hydrogen gas were introduced instead of introducing cm. In addition, when the steps (a) and (b) above are separately performed, the production is stopped, and the metal layer of the obtained metal substrate is observed.
It has a golden color, and as a result of surface analysis by X-ray electron spectroscopy, it was found that a titanium nitride layer having a thickness of 0.4 μm was formed. Example 11 The same as Example 10 except that in the step (c) of Example 10, the titanium nitride film was formed to have a thickness of 5.0 μm instead of being formed to have a thickness of 3.0 μm. A ceramic-coated metal material was manufactured in the same manner.

Example 12 (a) 50 made of high-speed steel (SS51) as a metal substrate
A flat plate of × 50 × 3 mm was used, and ultrasonic cleaning was performed using acetone to remove oil on the surface. Place this metal substrate and titanium as a vapor deposition material in a vacuum container, and
After evacuating to a pressure of × 10 ^-5 Torr or less, the metal substrate is heated to 500 ° C, and titanium is evaporated while applying a voltage of -500V to the metal substrate to 4 × 10 ^-5 Torr.
Under the conditions, the titanium coating was vapor-deposited by ion plating until the thickness of the titanium coating became 1.0 μm. Thus, the metal layer was formed. (B) Next, the evaporation of titanium is stopped, the heating temperature of the metal substrate is set to 700 ° C., while applying a voltage of −1000 V to the metal substrate, 160 sccm of nitrogen gas and 4 hydrogen gas are added.
0 sccm was introduced, and plasma treatment was performed for 60 minutes under the condition of 0.1 Torr. (C) Next, the heating temperature of the metal substrate is set to 500 ° C., while applying a voltage of −500 V to the metal substrate, titanium is vaporized and nitrogen gas as a reaction gas has a total pressure of 7 × 1.
It was introduced so as to have a thickness of 0 ⁻⁴ Torr, and the titanium nitride film was vapor-deposited by ion plating until the titanium nitride film had a thickness of 5.0 μm to produce a ceramic-coated metal material. In addition, when the above steps (a) and (b) were separately performed and the production was stopped, and the metal layer of the obtained metal substrate was observed, it had a golden color and surface analysis by X-ray electron spectroscopy. As a result, it was found that a titanium nitride layer having a thickness of 0.7 μm was formed.

Example 13 (a) The operation was carried out in the same manner as in step (a) of Example 12. (B) Next, the evaporation of titanium is stopped, the heating temperature of the metal substrate is maintained at 500 ° C., and while applying a voltage of −1000 V to the metal substrate, nitrogen gas is 80 sccm, hydrogen gas is 20 sccm, and argon gas is 50 sccm. Then, 50 sccm of helium gas was introduced, and plasma treatment was performed for 30 minutes under the condition of 0.1 Torr. (C) Next, a ceramic-coated metal material was manufactured in the same manner as in step (c) of Example 12. In addition, when the above steps (a) and (b) were separately performed and the production was stopped, and the metal layer of the obtained metal substrate was observed, it had a golden color and surface analysis by X-ray electron spectroscopy. As a result, it was found that a titanium nitride layer having a thickness of 0.8 μm was formed.

Example 14 (a) The same process as step (a) in Example 9 was carried out. (B) Next, the evaporation of titanium is stopped, the heating temperature of the metal substrate is maintained at 500 ° C., acetylene gas is introduced at 200 sccm while applying a voltage of −1000 V to the metal substrate, and the pressure is set to 30 at 0.1 Torr. Minute plasma treatment was performed. (C) Next, while maintaining the heating temperature of the metal substrate at 500 ° C. and applying a voltage of −750 V to the metal substrate, titanium is vaporized and acetylene gas as a reaction gas has a total pressure of 8 × 10 ⁻⁴ Torr. And the titanium carbide film was deposited by ion plating until the titanium carbide film had a thickness of 3.0 μm to produce a ceramic-coated metal material. In addition, when the above steps (a) and (b) are separately performed, the production is stopped, and the metal layer of the obtained metal substrate is replaced with X.
As a result of surface analysis by line electron spectroscopy, the thickness is 0.1 μm.
It was found that the titanium carbide layer was formed.

Example 15 (a) The same operation as in step (a) of Example 9 was carried out. (B) Next, the evaporation of titanium is stopped, the heating temperature of the metal substrate is maintained at 500 ° C., and while applying a voltage of −1000 V to the metal substrate, 60 sccm of nitrogen gas and 140 sccm of acetylene gas are introduced, Plasma treatment was performed for 30 minutes under the condition of 1 Torr. (C) Next, while maintaining the heating temperature of the metal substrate at 500 ° C. and applying a voltage of −500 V to the metal substrate, titanium is vaporized and nitrogen gas and acetylene gas are used as reaction gases at a flow rate ratio of 3: 7. Used, total pressure is 8 × 10 ^-4 T
Introduced so as to have an orr and a titanium carbonitride film of 3.
The same coating was vapor-deposited by ion plating to a thickness of 0 μm to manufacture a ceramic-coated metal material.
In addition, when the above steps (a) and (b) are separately performed, the production is stopped, and the metal layer of the obtained metal substrate is replaced with X.
As a result of surface analysis by line electron spectroscopy, thickness 0.2 μm
It was found that the titanium carbonitride film was formed. In addition, when the above steps (a) and (b) were separately performed and the production was stopped, and the metal layer of the obtained metal substrate was observed, it had a golden color and surface analysis by X-ray electron spectroscopy. As a result, it was found that a titanium nitride layer having a thickness of 0.8 μm was formed.

Example 16 (a) Stainless steel as a metal substrate (SUS304)
Using a flat plate of 50 × 50 × 2 mm manufactured by Mfg. Co., Ltd., ultrasonic cleaning was performed with acetone to remove oil on the surface. This metal substrate and chromium as a vapor deposition material are placed in a vacuum container, the interior of the container is evacuated to 1 × 10 ⁻⁵ Torr or less, and then the metal substrate is heated to 500 ° C.
While applying a voltage of V, chromium is evaporated and 4 × 10
^The chromium coating was deposited by ion plating until the thickness of the chromium coating became 0.5 μm under the condition of ⁻⁵ Torr.
Thus, the metal layer was formed. (B) Next, the evaporation of chromium is stopped, the heating temperature of the metal substrate is maintained at 500 ° C., while applying a voltage of −1000 V to the metal substrate, 200 sccm of acetylene gas is introduced, and the acetylene gas is set to 30 at 0.1 Torr. Minute plasma treatment was performed. (C) Next, while maintaining the heating temperature of the metal substrate at 500 ° C. and applying a voltage of −750 V to the metal substrate, chromium is evaporated and acetylene gas is used as a reaction gas at a total pressure of 6 × 10 ⁻⁴ Torr. And the chromium carbide film was deposited by ion plating until the chromium carbide film had a thickness of 3.0 μm to produce a ceramic-coated metal material. In addition, when the above steps (a) and (b) were separately performed and the production was stopped, and the metal layer of the obtained metal substrate was observed, it had a golden color and surface analysis by X-ray electron spectroscopy. As a result, it was found that a chromium carbide layer having a thickness of 0.2 μm was formed.

Tables 1 and 2 show the manufacturing conditions of the ceramic-coated metal materials of the above Examples and Comparative Examples.

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[Table 1]

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[Table 2]

The ceramic-coated metal materials obtained in the above Examples and Comparative Examples were used as samples for the following evaluations. (1) Surface hardness: A micro Vickers hardness meter (manufactured by Akashi Seisakusho Co., Ltd., Hard Nester, model MVK-E) was used and measured with a load of 10 g. The unit of surface hardness is kg
/ Mm ² (2) Wear resistance: # 400 sandpaper, pressure 1.5
After polishing 200 times at kg / cm ² , the appearance was observed and evaluated according to the following criteria. (Evaluation Criteria) O: No scratch is observed. Δ: Some scratches are observed. (3) Corrosion resistance: The sample was left to stand in a thermo-hygrostat set to a temperature of 60 ° C. and a humidity of 96%, and the appearance was observed every 24 hours to examine the number of days until the first occurrence of rust. (4) Adhesion: A scratch test with a diamond indenter was performed. The unit is N (Newton). The above evaluation results are shown in Tables 3 and 4.

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[Table 3]

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[Table 4]

As is clear from Tables 1 to 4, the ceramic-coated metal materials of the examples belonging to the present invention show good results in all of the evaluation items.

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Since the method for producing a ceramic-coated metal material of the present invention is as described above, it is possible to produce a ceramic-coated metal material which is excellent in corrosion resistance as well as high hardness and wear resistance. The metal material is
Ceramic-coated blades, electrical machinery, transportation machinery, machine tools, precision machinery, civil engineering construction machinery and their parts; tools; building materials; furniture materials; daily necessities such as tableware; ornaments; all other metallic material applications Can be suitably used.

Since the method for producing a ceramic-coated metal material of the present invention 2 is as described above, it is possible to obtain a ceramic-coated metal material which is excellent in corrosion resistance and adhesion as well as high hardness and wear resistance. Ceramic-coated metal materials include ceramic-coated blades, electric machines, transportation machines, machine tools, precision machines, civil engineering construction machines and their parts; tools; building materials; furniture materials; daily necessities such as tableware; ornaments; It can be suitably used for applications of all other metal materials.

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location C23C 28/04

Claims (2)

[Claims] 1. A ceramic layer made of a nitride, a carbide or a carbonitride of a metal of Group 4, 6, 8, 13 or 14 of the Periodic Table at least by a physical vapor deposition method or a chemical vapor deposition method on a metal substrate. 1. A method for producing a ceramic-coated metal material, which comprises coating one layer and contacting the surface of the ceramic layer with a nitrogen-containing gas, a carbon-containing gas or a mixed gas thereof by exciting them with plasma. 2. A metal substrate is coated with a metal layer made of a metal of Group 4, 6, 8, 13 or 14 of the periodic table by physical vapor deposition or chemical vapor deposition, and then the surface of the metal layer is covered with nitrogen. A gas containing carbon, a gas containing carbon or a mixed gas thereof is excited by plasma and brought into contact with each other to form a ceramic layer made of a nitride, a carbide or a carbonitride of the metal on the surface layer portion of the metal layer, and further the ceramic A method for producing a ceramic-coated metal material, characterized in that a ceramic layer made of the same elemental species as the ceramic layer is coated on the layer by a physical vapor deposition method or a chemical vapor deposition method.