JPS62127466A - Member deposited with ceramics - Google Patents

Abstract

PURPOSE:To develop a sliding member which has excellent adhesiveness to a Fe metallic base material and wear resistance and does not wear the mating material by forming an Fe layer contg. C at a high concn. on the surface of the base material of the sliding member then forming a hard ceramic layer thereon. CONSTITUTION:The ferrous base material 10 consisting of cast iron or free cutting steel as the member such as the shaft of a compressor sliding at a high speed is hung to the center of a cylindrical electrode 4 in a cylindrical reaction chamber 1 and a cylindrical diffusion member 5 is disposed on the outside thereof. After the inside of the reaction chamber 1 is evacuated to a reduced pressure, carboneceous gas such as CH4 or C2H6 is introduced into the chamber from a gas inlet 3 and a high-frequency voltage is impressed between the base material 10 and the electrode 4 to generate plasma by which the surface of the material 10 is carbonized. Gas such as SiH4, NH3 or BF3 is then introduced together with gaseous Ar into the furnace and the plasma discharge is executed in the same manner as in the previous time to form the hard ceramic layer of SiC, B4C, SiN, BN, etc., on the surface of the material 10. The sliding member having the excellent sliding characteristic is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a member coated with ceramics suitable for a member that slides at high speed.

[Prior Art] For example, members that are subjected to sliding at high speed, such as the shaft of a compressor, the camshaft of an engine, the laser scanner of a laser printer, and the guide rod of a printer, are susceptible to wear. Wear of moving parts has a significant impact on equipment life and performance. For this reason, hard and wear-resistant materials such as high-speed steel and cemented carbide are used for such high-speed wave sliding members. However, these materials have high material costs and processing costs, so if it is necessary to avoid higher costs, use relatively inexpensive materials such as cast iron or free-cutting steel. Measures are being taken to harden the surface and add lubricity. Furthermore, a technique has been proposed in which cutting tools are coated with high-hardness ceramics such as TiN and TIC to improve the wear resistance of cutting tools.

[Problems to be solved by the invention] However, surface hardening treatment includes quenching, and 11!
Treatments for imparting l1fl properties include tuftride treatment, Varco treatment, and coating treatment with black-dyed molybdenum disulfide, but all of these treatments have sufficient durability under harsh conditions of high load and high speed rotation. can't get it.

In addition, in hardening and tuftride treatments, the processing temperature is as high as 500°C or higher, so there is a risk of deformation of the base material during the treatment, so these treatments should not be applied to parts that require high dimensional accuracy. I can't.

Furthermore, if TiN or TIC is coated on a high-speed sliding member, the hardness of these ceramics is high, so the sliding member on the other side will be ground, and this grinding debris will adhere to the ceramic coating. There is a problem that it gets burned in.

This invention was made in light of these circumstances, and
It has excellent adhesion to the base material, excellent wear resistance, and does not grind the sliding mating member.
It is an object of the present invention to provide a member coated with ceramics in which the occurrence of seizure is suppressed.

[Means for Solving the Problems 1] A member to which the ceramic according to the present invention is adhered has a base material whose main component is iron, and an iron layer containing a high concentration of carbon on the surface of this base material. It is characterized by having a ceramic layer whose main component is silicon or boron and which is adhered to the base material after being formed.

[Function] As a result of various studies aimed at developing a ceramic material that has high hardness, excellent wear resistance, and does not grind the mating sliding material, the inventor of the present application has developed a ceramic material that is mainly made of silicon or boron. It has been found that the ceramic component satisfies these requirements. Furthermore, such ceramic materials can be deposited on the base material by sputtering, plasma CVD, ion blating, etc., but since the processing temperature is relatively low at 200 to 300°C,
Deformation of the base material during processing can be suppressed, and these ceramics can also be applied to members that require high precision.

However, these ceramics have the disadvantage that their adhesion to the base material is inferior to TiN and TiC. In particular, when the base material is cast iron such as a compressor shaft, it is practically difficult to form a film with these ceramics.

The inventor of the present application repeatedly conducted various experimental studies in order to stably and easily adhere these ceramics to a base material whose main component is iron, and as a result, the inventor of the present invention created a high carbon concentration region on the surface of the base material. It has been found that by forming these ceramics in advance, these ceramics can be deposited with high adhesion. The present invention was made based on such research results.

Ceramics that have high wear resistance and do not grind the opposing sliding member include silicon nitride (SiN), boron nitride (BN), and silicon carbide (S+C).
), boron carbide (BC), silicon oxide (Sin), silicon carbonitride (S i CX NY ), boron carbonitride (BC
X NY ), or silicon carbonate (S i CX OY
) etc. These ceramics can be manufactured by sputtering, ion blating, plasma CVD, thermal CVO
, photo-CVD, etc.
Plasma CVD is preferred in view of its adhesion to the base material and the possibility of lower temperature treatment.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The ceramic-covered member according to this example is manufactured as follows. First, a base material is obtained by processing and forming a block of cast iron or free-cutting steel into a predetermined shape, such as a shaft of a rotary compressor or a carriage guide of a printer. Next, the surface of this base material is carbonized to form a region containing a high concentration of carbon in the surface layer. Thereafter, the surface of the ffl material is coated with ceramics such as SiN. In the shaft or carriage guide manufactured in this way, the surface of the base material whose main component is iron is covered with ceramics such as SiN. Therefore, even if the sliding member slides on such a member at high speed, wear is suppressed and the sliding member is not ground.

Next, with reference to FIG. 1, a method of manufacturing a member coated with ceramics according to this embodiment by plasma CVD will be described. A cylindrical reaction chamber 1 is supported on a suitable support with its axial direction vertical, and is electrically suspended via an insulator 2. The inside of the reaction chamber 1 is evacuated by a mechanical booster pump, an oil rotary pump (not shown), etc., and is maintained at a vacuum level of about 10 −3 Torr. Various raw material gases are introduced into the reaction chamber 1 through a gas inlet 3 .

A cylindrical 1!1fI4 is installed in the reaction v1 coaxially with respect to its peripheral wall, and a cylindrical diffusion member 5 is installed coaxially with the electrode 4 between this electrode 4 and the peripheral wall of the reaction chamber 1. is set up. A plurality of gas flow holes 6 and 7 are opened in this 11fi4 and the diffusion member 5, respectively, and the gas introduced into the reaction chamber 1 through the gas introduction port 3 is passed through the gas flow through the diffusion member 5. The gas passes through the flow hole 7 and the gas flow hole 6 of the electrode 4 and is supplied to the center of the reaction chamber 1 . Thereby, the gas is uniformly diffused and supplied to the center of the reaction chamber 1. The electrode 4 and the diffusion member 5 are at the same potential as the reaction chamber 1, and the electrode 4 and the like are connected to a high frequency type [8, so that high frequency power is applied to the electrode 4.

At the center of the reaction chamber 1, a base material 1o is arranged at the axial center of the electrode 4 with its axial direction being vertical. A support member 11 is installed on the top plate of the reaction chamber 1 via an insulator 2, and this support member 11 is grounded. The base material 10 is suspended from the support member 11 and inserted into the reaction chamber 1. Since the base material 10 is also grounded like the support member 11, when high frequency power is applied to the electrode 4 from the high frequency 1a8, plasma discharge is generated between the 1fffi4 and the base material 10.

Using the apparatus configured as described above, first, the surface of the base material is carbonized to form a region containing a high concentration of carbon in the surface layer. In other words, after the inside of the reaction chamber 1 is evacuated to about 10-3 Torr, a gas containing carbon such as CF4 gas or CH4 gas is introduced into the reaction chamber 1 through the gas inlet 3 while continuing the evacuation by the pump. and the pressure inside the reaction chamber 1 is adjusted to, for example, 1 torr. Next, when high frequency power is applied between the electrode 4 and the base material 10 to generate plasma, the base material 10
The surface of is carbonized. In this case, if plasma is generated only with a gas containing carbon, there is a risk that a film formed by polymerization of carbon due to the plasma will be deposited on the surface of the base material. If this film is soft, the ceramic layer formed in the next step will easily peel off, which is undesirable.

For this reason, in the reaction blank, in addition to the carbon-containing gas, A
It is preferable to introduce a gas such as r gas, He gas, or N2 gas, and generate plasma with a mixture of these gases. This is because the mixture of Ar gas and the like makes it difficult for carbon to polymerize and facilitates the progress of the reaction between carbon and iron. This mixed gas is particularly inert,
Ar gas is preferable because it has high ionization energy. An example of general carbonization treatment conditions is shown below.

CH4 gas flow rate: 50SCCM Ar gas flow rate: 300SCCM Reaction pressure (degree of vacuum): 1. O Tor high frequency type crab 500W Processing time: 30 minutes In addition, in this carbonization treatment, the base material may be heated in advance, but when plasma is generated, the base material is heated by this plasma, so It is not necessarily necessary to provide special heating means.

Furthermore, the carbon supply source is not limited to the above-mentioned gases, but solids may also be used. In this case, carbon may be ejected from the carbon-containing solid using Ar plasma.

Following this carbonization treatment, a gas containing constituent elements of the ceramic to be coated is introduced into the reaction chamber 1, and the base material whose surface has been carbonized is coated with the ceramic.

When the ceramic to be coated has Si as a main component, 3-Si H4 gas or 5i2Hs gas, etc.
When the gas is a nitride, a gas containing N such as N2 gas or NH3 gas is mixed with the gas containing i, and when it is a carbide, a gas containing C such as CH gas or C2H6 gas is mixed, 02 gas or N20 when it is an oxide
A gas containing O such as gas is mixed.

When the ceramic to be coated has 8 as a main component, a gas containing 8 such as BF3 gas or 82 H6 gas may be used instead of a gas containing Sl. In order to form a film of 5iCxNy, an appropriate amount of CH4 gas is added in addition to S i H4 gas and N2 gas. Also, S
In order to form a film of i CX OY, CH4 gas may be added to a mixed gas of SiH4 gas and 02 gas or N20 gas.

Next, typical examples of the ceramic coating conditions and the layer thickness of the ceramic film formed will be described.

(a) For SiN SiH4 gas 8m: 100SCCMN2 gas flow rate: 300SCCM Reaction pressure 1,000 liters High frequency cylinder 500W Film forming time: 30 minutes Layer thickness: Approx. 3μm (b) For SiC SiH + gas flow rate : 100SCCM CH4 gas flow rate: 300SCCM Reaction pressure I, Otor high frequency cylinder 500W Film forming time: 30 minutes Layer thickness: Approximately 3 μm (C) For BN 8F3 gas flow rate: 100SCCM N2 gas flow rate: 300SCCM Reaction pressure 1 ．． Otor high frequency tube crab 500W Film forming time III: 30 minutes Layer thickness: Approximately 3 μm (d) For SiO S+H4 gas flow 1: 1001005 cc gas flow 1300sccM Reaction pressure crab 1. O-tor high frequency tube crab 500W Film forming time: 30 minutes Layer thickness: Approximately 3 μm The ceramics produced as described above are coated with high strength ceramics and have excellent wear resistance. stomach. A shaft for a rotary compressor was manufactured under each film forming condition described above, and 1000
Continuously operate for 30 minutes at rotation speeds of 0R, P, M, then 1
A 1000 hour durability test was conducted in a mode in which the machine was stopped for 0 minutes and then operated again for 30 minutes. It has been demonstrated that the shafts coated with each of the ceramics shown in (a) to (d) above do not cause seizure due to wear or peeling of the layers, and are extremely durable.

In this example, carbonization of the surface of the base material and coating of ceramics are performed by plasma CVD, but the method is not limited to this, and as described above, other methods such as sputtering or ion blasting may also be used. good.

[Effects of the Invention] According to the present invention, a ceramic layer is adhered with high adhesiveness even to a base material whose main component is iron, and a member with excellent wear resistance can be obtained.

This member does not grind the mating member on which it slides, and the occurrence of seizure is prevented.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an apparatus for manufacturing a member coated with ceramics according to an embodiment of the present invention. 1; reaction chamber, 2: insulator, 4; electrode, 8; high frequency power supply,
10; Base material

Claims (5)

[Claims] (1) A base material whose main component is iron, and a ceramic layer whose main component is silicon or boron, which is adhered to the base material after forming a layer of iron containing a high concentration of carbon on the surface of this base material. A member coated with ceramics, characterized by comprising: (2) The iron layer containing a high concentration of carbon is formed by glow discharge.
A member coated with the ceramics described in 2. (3) A member coated with ceramics according to claim 1, wherein the ceramic layer is formed by glow discharge. (4) The ceramics include silicon nitride, boron nitride, silicon carbide, boron carbide, silicon oxide, silicon carbonitride, boron carbonitride,
A member coated with a ceramic according to claim 1, characterized in that the ceramic is selected from the group consisting of silicon carbonate and silicon carbonate. (5) A member coated with a ceramic according to claim 1, wherein the ceramic contains at least one of hydrogen and a halogen element.