JPS6282047A - Support member comprising porous ceramic - Google Patents

Abstract

PURPOSE:To provide a support member excellent in physical characteristics such as abrasion resistance or the like and also having various characteristics such as durable strength and the prevention of a powder from detachment during use, by specifying the open void ratio of porous ceramic. CONSTITUTION:The titled support member comprises porous ceramic obtained by sintering a formed body without clogging the voids present therein and provided with open voids having a three-dimensional reticulated structure formed so as to have an open void ratio of 5-30vol%. The ceramic sintered body is shrunk by 5-15% in a linear shrinking ratio at the time of baking. As the porous ceramic, it is advantageous to use one having hardness as high as possible from the viewpoint of abrasion resistance and, for example, a porous body containing one or two or more kinds of Al2O3, SiO2, ZrO2, SiC, TiC, TaC, B4C, WC, Cr3C2, Si3N4, BN, TiN, AlN, TiB2, CrB2 and a compound thereof is pref. The filling ratio of lubricant is pref. 10pts.vol to 100pts.vol. of open voids.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) Undeveloped 1p) relates to bearing members which are used under severe conditions and which are relatively small, and in particular to bearing members formed from porous ceramics.

(Prior art) In recent years, various mechanical parts, repair connectors, kite parts, etc. have become smaller and smaller with the development of machinery and equipment, and moreover, in consideration of workability and economic efficiency, they have become increasingly smaller. There is a growing demand for something that can be used even under harsh conditions. Particularly, in the case of a supporting member that frequently comes into W4 contact with other members or requires a relatively high level of accuracy, this yellow requirement is ifI'jt. Examples of such supporting members include kite plates for wire dot printers.

An example of a supporting member is wired/top printer support!・The board slides the impact wire for printing +i
It is something that supports f ability. The impact wire is reciprocated by, for example, a solenoid when pre/winding,
The tip of the printer prints by hitting a ribbon. By the way, since this impact wire operates very quickly and reciprocates very many times, the supporting member that supports it is likely to wear out due to sliding with the impact wire.

Furthermore, in a dot printer, the smaller the distance between the dots constituting the characters, the easier the printed characters are to read, so the distance between the holes in the support member, ie, the kite plate for the wire dot printer, is preferably as small as possible.

Conventional guides for wire dot printers are made from a variety of plastic materials, such as glass photoetching materials, alumina sinter, ruby or sapphire, and the like. And the pre/tar head of the wire tontobrinta,
That is, generally, an impact wire having a circular cross section and made of hard metal such as tanogsten or carbide carbide is provided toward the guide at the tip.

For this reason, the guide plate made of plastic material has the disadvantage that if the impact wire supported by the guide plate is actuated suddenly and frequently as described above, the guide plate will wear out and have a short service life. In addition, it is difficult to align the holes in a slate with a guide plate made of materials other than photo-etched glass, which not only results in high costs but also tends to break, resulting in short service life. There are drawbacks.

- On the other hand, guide plates made of alumina sintered bodies, ruby, or sapphire have relatively high hardness, so machine oil
It is not only difficult and expensive to process the material by methods such as -, but also because it is relatively brittle.
- It is always difficult to drill circular holes with such small spacing as described above.

As a technique that has already been proposed, for example, Japanese Patent Application Laid-Open No. 1V+5
6-89962t; - There is a proposal in the publication.

According to this bulletin, “Wire door made of carbon +
Kite glue for printers (or react with oxidation [V element to convert the entire base to form a silicon carbide layer) 1
(all surfaces or distributed partial surfaces of the body)5
A wire characterized in that it is formed on a silicon oxide layer; This is generally difficult, as the generated silicon carbide particles grow large and the surface particles become rough, so the inner surface of the hole must be polished before it can be used.

Since this polishing process I is extremely difficult after the reaction of silicon carbide, it is not a sufficient technique in practice.

In general, ceramic sintered bodies have high hardness, high: 1L)
It has excellent chemical and physical properties such as high impact resistance and high strength at product temperature, as well as excellent abrasion resistance, oxidation resistance, and corrosion resistance, as well as good thermal conductivity and low coefficient of thermal expansion. It is widely used in durable materials such as wear-resistant sliding members such as mechanical seals and bearings, and pump parts that require corrosion resistance.

However, on the other hand, ceramic sintered bodies having high hardness, such as the above-mentioned alumina sintered bodies, ruby or sapphire, have the disadvantage that they are difficult to process by mechanical processing and are expensive. Especially like guide plates for wire dot printers.

For example, the vertical dimension is 6111 m, the horizontal dimension is 31, and the plate thickness is 1
As shown in Fig. 1, the holes are extremely small, about 9 to 24 holes with a diameter of about 200 to 300 mm, and have the disadvantage of high preparation costs. be.

Considering the current situation as described in 1- below, the inventor of the present invention
As a result of extensive research focusing on the fact that this type of ceramic-dry sintered body is particularly abrasive, we have found that the firing shrinkage that occurs when firing the ceramic can be adjusted appropriately. It was discovered that the porous ceramic produced by the method has relatively excellent additivity and is also useful in wear resistance, and the active use of this porous ceramic will produce advantageous results. I came to this conclusion.

(Problem to be solved by the invention) Unoccurred 1g) was made based on the actual situation and progress as described below, and the problem to be solved by the invention is These are friction and manufacturing difficulties.

The purpose of the present invention is to provide a support member that has physical properties such as abrasion resistance, as well as properties such as durable strength and prevention of powder falling off during use. be.

(F stage and action for solving the problems) The first L stage adopted by the present invention to solve the above problems is as follows.

It is made of a porous ceramic that has open pores in a three-dimensional network structure by sintering the pores existing in the formed body without clogging them, and the open porosity of this porous ceramic is 5 to 30% by volume. A support member made of porous ceramic, characterized by the following.

This means will be explained in more detail below. In the following explanation, ``Supporting'' includes not only the case where an object slides while being supported, but also the case where an object is statically supported inside.

The uninvented supporting member is composed of ceramic and
The solid sintered body is fired without clogging the pores existing in the formed body, and the bonding neck between each powder particle is reduced to 1.
It must be a porous material that has been obtained by developing the porous material into a -E-dimensional network structure and has open pores. The reason for this is that, in general, sliding members made of a dense sintered body, when abrasion powder is attached and detached from the ceramic sintered body during table movement, this detached abrasion powder is transferred to the member and the other member. This is because the material acts like an abrasive by intervening between the sliding surfaces, causing each sliding surface to become hot and abrasive. By using a porous body as the sintered body, even if the wear powder is released from the ceramic sintered body during sliding, this wear powder is quickly retained in the nearby pores. Since the abrasive action caused by the attached and detached wear particles is almost non-existent, it is extremely poor as a sliding member.In addition, the porous body with open pores in a three-dimensional network structure has excellent lubricant retention properties. Are better.

The porous ceramic constituting the support member of the imported IJ needs to have an open porosity of 5 to 30% by volume. The reason for this is that sintered bodies with open pores of less than 5% by volume have extremely low yield rates, and it is difficult to obtain supporting members with substantially high dimensional accuracy.
Also, since lubricant retention and t are reduced, Il￥￥
It is difficult to exhibit one slip characteristic to all characteristics. -force,
If the content is higher than 30% by volume, porous ceramics have low abrasiveness, making it difficult to use them in environments with particularly high PV values.

[7] The ceramic or lithium sintered body is preferably shrunk by 5 to 15% at a wire count of 1d0 during firing. The reason for this is that firing shrinkage strengthens the joints between the ceramic particles, which prevents the particles from separating.This firing shrinkage provides sufficient strength and wear resistance for the intended bearing member. This is because it can be used to add gender.

+iii It is advantageous to use a porous ceramic ac having as high a hardness as possible from the viewpoint of wear resistance. For example, A I, 03, SiOx, ZrO, S
i C= T r C, T a C, BaC, W C
, Cr3C,, S i, N4. BN, TiN, AlN
,TiB,,CrB.

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

Further, in the present invention, the porous ceramic may be used as a composite body in which the open pores are impregnated with a lubricant. This is because by retaining the lubricant within the open pores of the porous ceramic, the sliding properties of the bearing member can be significantly improved. Such a lubricant may be a fluorine-based oil or a silicone-based oil. As such oil,
fluoroethylene, fluoroester, fluoro 1,
Fluorinated oil selected from riazine, perfluoropolyether, fluorosilicone, derivatives thereof, or combination thereof, or silicone oil selected from methyl silicone, methylphenyl silico/, derivatives thereof, or combination thereof can be used alone or in combination.

These fluorine-based oils or silicone-based oils can be used in any form of liquid, grease, or wax. Note that these fluorine-based oils or silicone-based oils have excellent solvent resistance, chemical stability, and heat resistance, and therefore can provide extremely good thinning properties over a long period of time. Of course,
Instead of these fluorine-based oils or silicone-based oils, commonly used lubricating oils may be used as a method of impregnating such lubricants into the open pores of porous ceramics. For this, a general method θ can be applied, such as a method in which the porous ceramic is infiltrated into a lubricant whose viscosity has been lowered by heating, and the porous ceramic is impregnated in a vacuum or under pressure.

Further, when used as a kite for a wire dot printer and the printing ink itself has lubricating properties, this printing ink can also be used as the lubricant.

The filling rate of these lubricants is preferably at least 10 parts by volume 46 per 100 parts by volume of the open pores. The reason is that the lubricant charge 4Mj FI
'+ is less than 10 parts by volume, sufficient sliding characteristics (1
).

Next, a method for manufacturing the support member (10) according to the present invention will be explained.

Support member made of porous ceramic related to unexploded material (10)
In this method, ceramic powder as a starting material is formed into a predetermined shape, for example, a shaped body in the shape of a guide plate (11) for a wire dot printer, and then sintered without clogging the pores existing in this shaped body to form a porous body. It can be manufactured by making it with ceramic.

Molding the ceramic powder into a predetermined shaped product,
Various methods can be applied to bond the pores existing in the formed body without clogging them. A method of adding a substance that generates ceramic by reaction to powder and bonding by reaction sintering. A method of combining ceramic powder with a binder such as metals such as Co, Ni, Mo, or glass cement, and sintering under normal pressure. For bonding, a method of bonding by pressure sintering or a method of bonding by blending a thermosetting resin or thermo-TJF plastic resin with ceramic powder as a binder can be applied.

On the other hand, when obtaining a sintered body by self-bonding the ceramic particles themselves by pressureless sintering, it is advantageous to use starting materials having an average particle size of 10 m or less. The reason why it is advantageous to use grains with an average diameter of 10 μm or less is that if the average grain size is larger than 10 μm, there will be fewer bonding points between grains within the sintered body, which makes it possible to create a high-strength sintered body. This is because it not only becomes difficult to obtain, but also deteriorates the surface roughness.

In addition, when the sintered body made of the above-mentioned hardened material or nitride is produced by the pressureless sintering method, it is advantageous that the formed body has a density of 45 to 80% by volume.

The reason for this is that when the density of the formed body is lower than 45% by volume, there are fewer contact points of the ceramic particle phase m, which inevitably leads to fewer bonding points, resulting in a sintered body of a strong piece with f:+'l. densities higher than 80% by volume are difficult to produce.

(Example) Next, 5 Examples will be used to explain the present invention. This is about cases where

The average particle size is 0.28 m, and the content of β-type crystals is 94.6
Silicon carbide powder with East Moat%! 00 'i! Boron carbide powder for counterfeit parts! Core mass part, carbon black powder type 2 ψ part,
5 parts of carbonyl alcohol and 300 parts of water were mixed in a ball mill for 5 hours, and then dried overnight. In addition, the silicon carbide powder has a carbon content of 0, 29 i
amount%, oxygen O, 17fiQ%, iron 0.03wt-1%
, contained 0.03% by weight of aluminum.

Collect an appropriate amount of this dried material and use a metal mold to
It was molded at a pressure of t/cm" and shaped as shown in Figure 1, ff, Gmm x 3.3m + lIX lf - size 1.1
A produced body with a mm density of 1.76 g/cm7 (55% by volume) was obtained.

Then, a diameter of 2141g was drilled into this formed shape using a carbide drill.
Nine holes were made as shown in Figure 1.

This formed body was placed in a graphite crucible and fired for 10 minutes at a temperature of 1900'C in an argon gas atmosphere at atmospheric pressure.

? 1? -The density of the sintered body is 2.59g/crn'
It had fine open pores uniformly distributed in the knee dimension (rj), and the open porosity was about 16% by volume.

Furthermore, the wire number fi ratio for the produced body was within the range of 12.5±0.07% in any direction, and the dimensional accuracy of the sintered body was within ±55 folds. In addition, when the average bending strength of this sintered body was measured, it was found to be 45 kgf/mrn
'The strength was high.

Next, the inner surface of the pores of the wire F top J nonta guide plate (11) formed in this manner was polished, and the open pores were impregnated with perfluoroalkyl polyether in an amount of 54 pores to fill approximately 77 pores of the pores. It was impregnated with %.

This second embodiment is for the case where an alumina guide plate (11) for a wire dot printer is manufactured as a supporting member (lO).

・[・Uniform particle size is 0.4 gm, AlzO3 content is 90 tons ψ%, S i O, content is 7 i + i)%
α-type alumina powder 100Φ; To the stop part, 2 parts polyvinyl alcohol, part X, 1 part polyethylene glycol, 0.5 parts stearic acid, and 10 parts water.
0 ton jj parts were blended, mixed in a ball mill for 5 hours, and then left to dry overnight.

1. Collect this dried material appropriately and use a metal press.
It was molded at a pressure of 5 t/cm' to obtain a molded body (having the same shape as in Example 1). Note that the gradual opening of this generated form is 2
．． It was 3 g/cm' (59%).

1) The formed body f7 was charged into an alumina crucible and fired at a temperature of 1400° C. for 1 hour in air at atmospheric pressure. The density of the obtained sintered body was 3.31 g/cm', and it had fine open pores uniformly distributed in five dimensions.
Its open porosity was approximately 14 volume Jar%.

In addition, the linear shrinkage rate for the formed body was within the range of 11.7 ± 0.07% in any direction, and the
The j method accuracy was within 5 μm. In addition, when the average bending strength of this sintered body was determined by ΔIII, it was 17.2 kg.
f/m rn' and t had an intensity of 1.

Next, the pores [m] of the wire don't printer guide plate (11) formed in this way were polished and the open pores were impregnated with perfluoroalkyl polyether in a vacuum to fill approximately 60% by volume of the voids. Impregnated.

When the wire dot printer Kawa Kite & (11) manufactured in this way was attached to an actual printer and a durability test was conducted, it was found that the handling of a conventional plastic kite was approximately 1
．． 500 million dots, and the glass kite plate cost about 300 million dots, making it difficult to use, whereas the kite plate (11) for printers according to the present invention costs more than 500 million dots.
It was confirmed that the material had the durability to withstand use for 1 minute.

(Effects of Issue 151) As described in detail below, the support member (1) according to the present invention takes the wire dot printer river kite board (11) as an example.
0) does not have the difficulty of processing relatively high hardness materials such as conventional alumina sintered bodies, ruby or sapphire, and can be manufactured at a low cost, at least for the processing cost.

In addition, the supporting member (10) according to the present invention can be sintered without clogging the pores existing in the formed body, and also shrinks during firing! Since it is fired in such a way that the A polarity occurs, the pore diameter of each open pore is small, making it possible to use liquid lubricants such as fluorine-based oil as well as resin as a lubricant. Rather, it is possible to improve lubricant retention by 1-5 times.

Moreover, the support member (10) according to the present invention has Cera E y
The wood itself has various properties, especially high hardness, abrasion resistance, excellent heat resistance, corrosion resistance against chemicals such as ink, and is suitable for use in environments with changes in temperature and temperature. , its excellent properties can also be utilized as is.

Note that the supporting member according to the present invention is sl t as shown in L.
l< Do not use a kite for a wired/top printer, and do not use other parts to support the pond parts. It goes without saying that similar effects can be achieved with the support member that supports the.

4, 14 Blood++i 'It Explanation 1 [, 4 is an example of the support member according to the present invention [・
FIG. 5 is a perspective view of a guide plate for a print printer.

Claims (1)

[Claims] 1.) A porous ceramic having open pores in a three-dimensional network structure by sintering without clogging the pores existing in the formed body; A support member made of porous ceramic, characterized in that the porosity is 5 to 30% by volume. 2.) The porous ceramic has a linear shrinkage rate of 5 to 1
The support member according to claim 1, characterized in that the support member has been subjected to 5% firing shrinkage. 3.) The porous ceramic is made of Al_2O_3, Si
O_2, ZrO_2, SiC, TiC, TaC, B_4
C, WC, Cr_3C_2, Si_3N_4, BN, T
The support member according to claim 1, characterized in that the support member mainly contains one or more selected from iN, AlN, TiB_2, CrB_2, or compounds thereof. 4.) The supporting member according to claim 1, wherein the porous ceramic has an average grain size of crystals of 10 μm or less. 5.) The support member according to claim 1, wherein the open pores are filled with a lubricant. 6.) The support member according to claim 1, wherein the lubricant is filled in an amount of at least 10 volumes per 100 volumes of open pores of the porous ceramic.