JPS62132785A - Precision standard part consisting of ceramic composite body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of use of # industry) The present invention relates to precision mold parts used in precision/F: Δ11 constant/precision machining.

(Prior art) Viscosity measurement - When performing precision addition, etc., use a ridge value ruler or a right angle Various precision 1111 fixed balls such as master are used.These 311 fixed upper J
Precision standard parts that make up L (this part itself is A)
11L regular construction 1), it is of course necessary that the reference planes and lines, etc., be accurate and not easily deformed even after long-term use, and must be suitable for frequent use. It is also necessary that the material has the desired strength and that it is easy to manufacture.

In addition, precision 4! 4 constant machines/precision machining - [For machines, etc., it is necessary to configure pairs such as "rolling" and "sliding".
Second, various precision paired parts such as guide rails, guide shafts, or reference columns are used. Such precision paired parts must have a certain level of rigidity as well as certain sliding characteristics because they must support various types of equipment such as measuring equipment and cameras in a movable manner. Ru. In addition, the precision pair parts themselves may have to be moved while supporting various VI devices, and in such cases, it is necessary to reduce the movement inertia of the precision pair parts to improve operability and high performance. Speed positioning cannot be performed.

Various precision standard parts such as precision "F" all fixed tools used for precision machining, precision measuring machines, precision processing machines, etc., such as paired parts, etc. Generally, cast iron, carbon steel, stainless steel, and stone are used. However, when precision reference parts are formed from these materials, the use environment is difficult because the coefficient of thermal expansion of these materials is relatively large. It is difficult to reduce the above-mentioned movement inertia because the influence of temperature changes is large, and these materials are relatively common.
When precision reference parts are made of metal, they are easily attacked by acids and alkalis, and may rust due to moisture.

Such precision reference parts are unsuitable for use in precision measurement, precision machining, and the like.

This kind of precision to eliminate the drawbacks in materials such as cast iron, carbon steel, stainless steel, stone, etc.). (Ceramics are attracting attention as materials for semi-components. In other words, ceramics have various advantages such as high mechanical strength, low coefficient of thermal expansion and little temperature change, and excellent corrosion resistance against acids and alkalis.) This is because it has the following characteristics and is suitable as a material for precision reference parts.

However, ceramics have high hardness.

Particularly when the material is sintered to a fine IF quality, mechanical processing after sintering is quite difficult. For this reason, it is conceivable to perform a predetermined process in consideration of firing shrinkage in the state of the formed body and then fire this. However, even if such considerations are taken into account during firing, if the precision standard part is long, the dimensional accuracy will inevitably be inconsistent, especially for precision machining with a constant δ that requires high dimensional viscosity. In order to construct the standard parts using this ceramic, a considerably high level of technology is required, which increases the product price! It is also the cause of

(Problems to be solved by the invention) The present invention has been made in view of the following circumstances.
The problem to be solved is the difficulty of processing when attempting to construct precision (1ti) quasi-components using ceramics.

The purpose of the present invention is to improve the machinability of ceramics, thereby making full use of the various characteristics of ceramics, and to create ceramics that are suitable for precision measurement and precision machining, and have excellent sliding properties. Our goal is to provide precision parts (semi-parts) made from materials.

(Means for solving the problem) The method adopted by Bankogi Hirari 1 to solve the above problem is to create a three-dimensional structure by sintering without clogging the pores existing in the formed body. A ceramic composite body comprising a porous ceramic body having open pores in a network structure, the open pores of the base body being filled with a lubricant. It is a precision reference part consisting of a body.

This means will be explained in more detail below.

The precision reference part according to the present invention is obtained by firing the ceramic sintered body constituting the part without clogging the pores present in the formed body, and has a three-dimensional network. It must be a porous body with an open pore structure. The reason for this is that if the pores are closed when the ceramic powder is bonded, the lubricant described below will not be filled in the independent pores, which is the reason for this.
This is because it becomes difficult to obtain quasi-parts (the target density), whereas porous bodies with open pores in a three-dimensional network structure are extremely suitable for filling with lubricant. That's why.

In addition, the reason why the ceramic sintered body must be a porous body is that this sintered body can ensure ease of machining in finishing work when completing semi-parts. This is because it is extremely difficult to finish the surface of dense ceramics by mechanical grinding, but it is relatively easy to mechanically grind porous materials. It is.

Furthermore, in Appendix 8, by making the ceramic sintered body into a porous body with open pores with a two-dimensional, network structure, it is possible to improve the quality of livestock products (half parts) made of general sintered bodies. When wear particles are removed from the ceramic sintered body by other parts that slide on this L, the removed wear particles are interposed between the sliding surfaces between the members and the sliding characteristics are significantly deteriorated. However, according to the present invention, by using a porous body as the ceramic sintered body constituting the reference part, it is possible to reduce wear particles from the ceramic sintered body during sliding.
Even if it comes off, this wear powder is quickly retained in the nearby pores, and there is almost no deterioration of the sliding characteristics due to the detached wear powder, making it extremely excellent as a precision base I4A component.

As this ceramic porous body, it is advantageous to use one with as high hardness as possible from the viewpoint of wear resistance.For example, AMMo2i, SiO□, ZrO, S
i C, T i C, TaC, B, C, WClCr, C
Yo, S i, N,, BN, TiN, AJIN, TiB.

It is preferable that the porous body mainly contains one or more selected from , CrB, or these compounds.

In addition, it is preferable that the average grain size of the crystals in this ceramic porous body is 507 zm or less.The reason is that if the average grain size is larger than 501 zm, the surface roughness of the sintered body surface becomes large and precision This is because the sliding surface of the reference component is less likely to have Vz slippage, and the dimensional accuracy of the jl'j dense reference component itself is poor.

The average grain size of the crystals constituting the ceramic porous body is most preferably 20 gm or less.

The ceramic porous body constituting the precision reference component of the present invention preferably has open pores of 5 to 50% by volume. The reason for this is that if the open pores -t< is less than 5%, substantial lubricant impregnation or filling r5 will be reduced, making it difficult to fully exhibit the lubricating properties. If the content is higher than 50% by volume, the abrasion resistance of the ceramic porous body will be low, making it difficult to use it as a precision reference part for machines and devices that require particularly high precision.

Further, in the present invention, it is necessary to use the ceramic porous body as a composite body in which the open pores of the ceramic body are impregnated or filled with a lubricant. The reason for this is that by filling or impregnating the open pores of the porous ceramic body with a lubricant, the sliding properties of the precision base (component) can be significantly improved.

Various substances can be used as such a 4!1 lubricant, and for example, it is advantageous to use resin or oil.

Examples of the tree 11u include epoxy resin, polyimide resin, trimazine resin, polyparaban resin, polyamideimide resin, silicone resin, epoxy silicone resin, 1fti of acrylic acid resin, and methacrylic acid resin.

Aniphosphoric acid resin, phenolic resin, urethane resin, furan resin, )-N resin, acetal resin, nylon resin, polyethylene resin, polycarbonate resin, polyethylene terephthalate resin.

Styrene acrylonitrile resin, polypropylene resin,
Resins selected from polyurethane resins and polyphenylene sulfide resins can be used singly or in combination.

In addition, the oil includes fluoroethylene, fluoroester, fluorotriazine, perfluoropolyether, fluorosilicone, derivatives thereof, or polymers thereof, fluorine-based oil, methylsilicone, and polymers thereof. Silicone oils, naphthenic oils, or paraffinic oils selected from luphenyl silicone, derivatives thereof, or polymers thereof can be used.

These oils can be used in any form of liquid, grease or wax. In addition, these fluorine-based oils and silicone-based oils are
It has excellent solvent resistance, chemical stability, and heat resistance, so it has extremely good lubrication properties over a long period of time! In addition, the naphthenic oil and paraffinic oil have the advantage that they have low compatibility with various chemical agents and are unlikely to leak out even if they come into contact with these chemical agents. It is. Of course, a commonly used lubricating oil or the like may be used instead of these oils.

It is advantageous for the filling rate of these lubricants to be such that at least 100 volume parts of the above-mentioned open pores are filled. The reason is the lubricant filling! 11 is 1
This is because if the volume is less than 0 volume, it is difficult to improve the lubrication characteristics of the precision reference component according to the present invention.

Methods for filling the open pores of the ceramic porous body with a lubricant include a method of heating the resin to melt it and impregnate it, and a method of dissolving the resin in a solvent when the lubricant is a resin. A method of impregnating the porous body with the resin is a method of impregnating the porous body with a large amount of resin, and then adding the resin to the polymer.

The method of baking the resin at its melting temperature after drying can be applied by some people.

In addition, when the lubricant is oil, add this oil to +i
A method for filling the open pores of the porous ceramic body described in ij is to immerse the porous ceramic body in a lubricant whose viscosity has been lowered by heating, and impregnate it in the air or under pressure. A general method such as υ; can be applied.

Next, a general method for manufacturing precision parts made of this ceramic composite will be explained.

The precision reference part made of a ceramic composite according to the present invention can be produced by using ceramic powder as a starting material in an arbitrary shape.
For example, it is formed into a columnar or beam-shaped formed body, and sintered to form a ceramic porous body without clogging the pores existing in this formed body.
/Can be manufactured by filling the open pores of a woody porous body with a lubricant.

It is preferable that the ceramic powder as the starting material has an average particle size of 50 pm or less. The reason for this is that when ceramic powder with an average particle size larger than 50 pm is used, there are fewer bonding points between the particles, which not only makes it difficult to produce a high-strength porous body, but also makes the surface rougher. This is because the accuracy deteriorates, and above all, it is preferably 20 gm or less.

As a method for molding the ceramic powder into a formed body of any shape and sintering it without clogging the pores present in this formed body, various methods V can be applied,
For example, a method in which ceramic powder itself is self-bonded by pressureless sintering or pressure sintering, a method in which a substance that generates ceramics is added to ceramic powder and bonded by reaction sintering, and ceramic powder is bonded with glass cement, etc. A method can be applied in which a binder is blended and bonded by normal pressure sintering or pressure sintering.

Furthermore, a method for forming this precision reference component using silicon carbide as a material will be explained in basic terms.

That is, in this manufacturing method using silicon carbide as a material, a silicon carbide powder containing at least 30% of β-type crystal silicon carbide is used. After forming the starting material to form the L-form into the desired product shape, it is heated and fired in a non-oxidizing gas atmosphere within the range of 1700 to 2100°C, and the riverine agent is added to the open pores thus formed. It is advantageous to fill by υ.

The reason why the silicon carbide powder used in this method is a fine powder with an average particle size of 1 Opm or less is that the average particle size is 10 μm.
The formed body molded from powder with a particle size of m or less has a relatively large number of contact points with the particle phase 1j, and the thermal activity at the firing temperature of the silicon carbide powder is large, and the movement of atoms between silicon carbide particles is extremely large. Therefore, bonding of the silicon carbide particle phase is extremely likely to occur. Therefore, if silicon carbide powder having such a particle size is used, a high-strength sintered body can be obtained even with a relatively low density. In particular, more suitable results can be obtained when the average particle size of the silicon carbide powder is 5 μm or less.

In this method, the reason why a silicon carbide powder containing at least 30% of iR silicon with β-1 crystals is used as the silicon carbide powder is that β-type crystals are low-temperature stable crystals that are synthesized at relatively low temperatures. Yes, during sintering)? Mutual bonding of silicon oxide particles is likely to occur, and the bonding rate is relatively low! This is because a high-strength sintered body can be produced even at an FI degree, and particularly preferred results can be obtained when the silicon carbide powder contains 50% or more of β-type crystals.

In this method, the starting material contains at least one selected from boron, aluminum, iron, chromium, lanthanum, titanium, yttrium, erbium, or compounds thereof.
It is right that it contains I%. The reason is that the substance has the effect of promoting sintering of silicon carbide, and it is possible to produce a high-strength sintered body because it promotes bonding between silicon carbide particles during sintering. , and the content of the substance is 0.01 to 5.0.
The reason why it is advantageous to keep the content within the range of 0.01% is because if the content is less than 0.01%, it will have little effect on promoting the bonding of the silicon carbide particle phase during sintering. , On the other hand, if the amount is more than 5.0% by weight, the sintered body of the substance will contain more stars, and the original characteristics of silicon carbide will be lost.

In this method, a carbon source that leaves Mra carbon upon firing can be added to the starting material.

As such a carbon source, any material that exists in a carbon state at the start of sintering can be used, such as phenol resin, lignin sulfone 115, polyvinyl alcohol, cornstarch, sugar, coal tar pinch,
Various organic substances such as alginates or pyrolytic carbons such as carbon black and acetylene black can be advantageously used. Such free carbon is
When present at the same time as the above substances, it suppresses crystal growth.

This is effective in obtaining a porous silicon carbide sintered body having 411 fine pores.

In addition, the content of free carbon is as follows: starting material 1
Advantageously, it is not more than 5 parts by weight relative to 00 parts by weight. The reason for this is that even if more than a portion of 5jT(+@F is added, the effect will not change, but on the contrary, more of the 1111 residue will remain in the sintered body, and the strength of the sintered body will deteriorate. .

According to the above method, after forming the starting raw material 1 into a formed body, it is heated to 1,700 to 2,100 in a non-oxidizing gas atmosphere.
By heating and sintering within the range of °C, the density can be reduced to 2.
．． 1 to 3.0 g/cm' and strength is 30Kgf/m
It is possible to produce a silicon carbide sintered body having a particle diameter of rn' or higher. The reason why the firing temperature is set in the range of 1700 to 2100°C is that if the firing temperature is lower than 1700°C, the bonding between particles is insufficient, making it difficult to obtain a sintered body with high strength. This is because if the temperature is higher than 2100°C, the sintered body tends to become dense, making it difficult to obtain a porous silicon carbide sintered body.

The porous silicon carbide sintered body has a density of 2.1 to 3.0 g/
If the strength is 30 Kgf/m m' or more at am', it is right-handed. The density is 2.1~3.0 g/cm
The reason why it is advantageous to be within the range of 2.1 g/cm' is because the sintered body with the density smaller than 2.1 g/cm' has fewer bonding points between silicon carbide particles.
This is because it is difficult to produce a sintered body with a strength of more than 3.0 g/cm", and on the other hand, a sintered body with a strength greater than 3.0 g/cm" has a ratio of open pores to the pores contained in the sintered body. This is what gets smaller. Also, the strong one ship is 30
The reason why it is advantageous to have Kgf/m rn' or more is as follows.
If the strength is less than 30 Kgf/m m', it will be easily damaged during use and will not be able to withstand practical use. In particular, if the strength is 40 Kgf/m m' or more, more suitable results will be obtained. 4 The strength in this method is the average bending strength IW.

Next, the precision reference component according to the present invention will be explained in detail with reference to examples.

(Example) The average grain size is 0.28 m, the content of β-type crystals is 94.6
11% of silicon carbide powder, 1 part of boron carbide powder, 2 parts of carbon black powder, 1 part of polyvinyl alcohol, 300 parts of water.
+@'i part was blended and mixed in a ball mill for 5 hours, followed by blow drying. Note that the silicon carbide powder has free carbon 0.
．． 29 %, oxygen 0.17%, iron 0.03%
Tun ¥%, aluminum Q, Q3 balls! It contained ^%.

One sample of this dried material of appropriate length was molded and held in an argon gas atmosphere at 1800°C for 10 minutes to form a sintered body.
Ta.

The obtained sintered body has a density of 2.59 g/cm', a strength of 45 kgF/m, and has fine open pores uniformly distributed three-dimensionally, and the open porosity is approximately 16 by volume. %
Met.

Next, this sintered body was impregnated with a two-component type epoxy resin by vacuum F, and then cured at a temperature of about 150°C.

The proportion of the epoxy resin in the open pores of this sintered body was approximately 96% by volume.

When this resin-filled sintered body was cut with a diamond wheel, it was much easier to cut than conventional dense silicon carbide sintered bodies, and the diamond wheel wore out very little. Ta.

(Effect of the invention) As detailed above, the guide rail and guide shaft.

The viscous part (semi-part) according to the present invention, which is used as a standard image ruler, etc., is made by sintering without clogging the pores existing in the formed body, thereby making the open air of the three-dimensional network structure coplanar. It is characterized by forming a porous ceramic body and filling the open pores of the porous ceramic body with a lubricant, which results in superior machinability compared to dense ceramics. Moreover, it was possible to make a precision reference part that takes advantage of the other characteristics of ceramics as they are.In other words, according to the present invention, the precision reference part has excellent wear resistance, oxidation resistance, and corrosion resistance, which are necessary for a precision reference part. Of course, it has excellent composition and strength! 1 yen -
It is possible to provide a precision reference component that can be made into a j-type and can reduce movement inertia. Moreover,
The precision reference component according to the present invention has relatively good thermal conductivity and thermal expansion coefficient, and can reduce the influence of temperature changes in the usage environment.

In addition, the precision Norbero parts related to the undeveloped Ill are filled with lubricant in the open pores of the ceramic porous body.
Regarding the precision, (even if the mold parts are N: M fHI,
The resin within the open pores can then leak out to the surface. This is because this precision reference part is made of a porous ceramic material, so there is no rust at all, so there is no clogging of the open pores, and the nη lubricant does not build up over a long period of time. This is because leakage to the surface is prevented. Therefore, the precision reference component according to the present invention does not cause any change in the necessary lubrication characteristics over a long period of time, and can maintain its sliding characteristics at the initial value for a long period of time.

Furthermore, since the precision reference component according to the present invention has excellent lubrication properties as described above, it is most suitable as a precision reference component that slides into contact with each other while repeatedly starting and stopping relatively quickly. It is possible.

In addition, when the precision reference part according to the present invention is formed of silicon carbide, the precision reference part is made of silicon carbide.

Not only can it be made with excellent oxidation resistance and wear resistance, a low coefficient of thermal expansion, and excellent machinability, but it can also be made with extremely high hardness. Therefore, it can be used under the condition of Pv value.

From L

Claims (1)

[Claims] 1.) A precision reference part used in precision measurement, precision processing, etc., which has open pores in a three-dimensional network structure by sintering without clogging the pores existing in the formed body. The substrate is a ceramic porous body comprising:
A precision reference part made of a ceramic composite, characterized in that the open pores of the base body are filled with a lubricant. 2.) As the ceramic porous body, Al_2
O_3, SiO_2, ZrO_2, SiC, TiC, T
aC, B_4C, WC, Cr_3C_2, Si_3N_
4. The precision reference component according to claim 1, which mainly contains one or more selected from BN, TiN, AlN, TiB_2, CrB_2, or compounds thereof. 3.) The precision reference component according to claim 1 or 2, wherein the ceramic porous body has an average grain size of crystals of 50 μm or less. 4.) The precision reference component according to any one of claims 1 to 3, wherein the ceramic porous body has an open porosity of 5 to 50% by volume. 5.) The precision lubricant according to any one of claims 1 to 4, wherein at least 10 parts by volume of the lubricant are filled with respect to 100 parts by volume of open pores of the ceramic porous body. Standard parts.