JPH02263834A - Formed body for sliding surface, track for high-speed moving unit and usage of formed body for sliding surface - Google Patents

Abstract

PURPOSE:To obtain the subject formed body, containing a netlike tetrafluoroethylene resin entangled with a heat-resistant resin and further inorganic powder, capable of reducing friction and abrasion of rubber products and useful as running road surfaces for linear motor cars, etc. CONSTITUTION:The objective formed body 10 obtained by using (A) tetrafluoroethylene resin 2, (B) inorganic powder 1 and (C) a heat-resistant resin 3 other than the component (A) as principal components and providing a mutually intervened network structure in which the netlike component (A) is mutually entangled with the netlike component (C) that is contained therein using at least pressure or heat. Furthermore, the component (B) is composed of at least one selected from the group of metal oxides (e.g. alumina), metal nitrides (e.g. silicon nitride), metal carbonates (e.g. silicon carbide), etc., and the average particle diameter is preferably within the range of 1-20mum.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a sliding surface forming body and a running track for high-speed moving objects, and in particular is used as a mating material for rubber products such as rubber tires to form a sliding surface and A smooth surface forming body for achieving wear prevention and low friction of products, a running track for high-speed moving bodies to prevent wear of rubber tires of high-speed moving bodies such as linear motor cars and aircraft, and a method for using the above-mentioned smooth surface forming body. .

[Prior art and problems to be solved by the invention] Rubber products are used as connectors for rubber tires of automobiles, aircraft, linear motor cars, etc., various pipes, etc. due to the excellent properties of rubber such as elasticity and high coefficient of friction. It is used in a wide range of applications, including O-rings used in parts, rubber sheets for vibration prevention, and table legs. As the uses of rubber products expand, the environments in which they are used have become harsher, and especially for rubber tires on high-speed moving vehicles such as linear motor cars and aircraft, it is necessary to cope with the friction phenomenon of rubber tires. Rubber is actually being used in environments that far exceed the properties originally required of rubber. For example, in the aircraft industry, the rubber tires of aircraft are subject to significant wear during takeoff and landing, and this trend is only worsening as aircraft weight increases.Currently, rubber tires do not have to be replaced after just a few hundred landings. This is not the case, and a huge amount of costs are being incurred.

Under such usage environments, the rubber properties of rubber products include sliding properties, that is, a low coefficient of friction, in order to prevent rubber wear and damage caused by heat generation, as well as the conventional anti-slip function. There is a need. In this way, rubber products are required to have multiple functions instead of conventional single functions.

On the other hand, in cases where safety is extremely important, such as in linear motor cars and airplanes, there is a problem in that the rubber tires must be replaced after several hundred landings, making them uneconomical.

The present invention focuses on the above-mentioned frictional wear phenomenon of rubber products, and provides a smooth surface forming body capable of reducing significant wear of rubber products by forming a smooth surface as a mating material of the rubber products, and this smooth surface forming body. The purpose is to provide instructions on how to use the body.

Another object of the present invention is to provide a running track for a high-speed moving body that prevents significant wear of the rubber tires of the high-speed moving body and protects the running road surface.

[Means to solve the problem]

In order to achieve the above object, the smooth surface forming body of the present invention has a polytetrafluoroethylene resin, an inorganic powder, and a heat-resistant resin other than the polytetrafluoroethylene resin as its main component, and is made of polytetrafluoroethylene resin in a network shape by at least pressure or heat. The ethylene resin and the network-like heat-resistant resin are intertwined with each other and have an intermeshed network structure containing inorganic powder.

The inorganic powder can be selected from the group consisting of metal oxides, metal nitrides, metal carbides, metal sulfides, pure metals, alloys, and graphite.

At least one metal oxide selected from the group consisting of alumina, silica, zirconia, titania, calcia, copper oxide, iron oxide, molybdenum oxide, and magnesium oxide can be used.

At least one metal nitride selected from the group consisting of silicon nitride, aluminum nitride, and titanium nitride can be used.

Silicon carbide can be used as the metal carbide.

At least one pure metal selected from the group consisting of copper, aluminum, gold, silver, titanium, iron, molybdenum, vanadium, nickel, and tungsten can be used.

At least one alloy can be selected from the group consisting of stainless steel, brass, aluminum alloy, and magnesium alloy.

The average particle size of the inorganic powder can be in the range of 1 to 20 μm.

The heat-resistant resin can be selected from the group consisting of polyphenylene sulfide, polyamideimide, polyimide, polyether sulfone, polyether ether ketone, epoxy resin, phenol resin, and ester resin.

The porosity of the smooth surface forming body can be in the range of 0.5% to 30.0%.

Further, the present invention uses the above-mentioned smooth surface forming body as a material for a running track for a high-speed moving body.

Further, the running track for a high-speed moving body of the present invention is constructed by arranging the sliding surface forming body configured as described above at the initial contact portion with the rubber tire of the high-speed moving body. .

[Effect]

In general, rubber products can be regarded as one highly fluid macromolecule whose molecules are crosslinked by vulcanization. Therefore, when a certain amount of force is applied, it becomes possible to penetrate into the unevenness of the surface of the mating material or to get as close to the surface of the mating material as possible. Here, when the rubber product undergoes extreme deformation as described above, the rubber is in an adhesive state or a state similar to a sticky state, and becomes a quasi-crystalline state. An explanation of these matters in terms of friction and wear development is as follows. The rubber surface deforms and follows the movement of the rubber or the mating material, and at the limit of rubber deformation it becomes a quasi-crystalline state, and in this state maximum resistance acts on the rubber. When the deformation limit is exceeded, the rubber surface is destroyed, the destruction energy is converted into heat, and this heat turns the rubber into a liquid state and seizes it to the mating material, causing unilateral wear of the rubber. This phenomenon is a typical friction and wear phenomenon.

Wear due to this phenomenon is greatest when either the rubber product or the mating material comes into contact while the other is stationary and the other is moving at high speed, or at the moment when both are stationary and both or one starts moving. become. In many cases,
At the initial stage of contact or at the moment when movement begins, in other words, at the moment just before the deformation limit of the rubber, frictional resistance is at its maximum and appears as localized wear such as uneven wear, so it is recommended not to use rubber products in such areas. is not very desirable.

Therefore, if the friction is low both in the initial stage and in the steady state of friction, the range of applications of rubber products will be widened.

Therefore, in the present invention, in order to widen the range of application of rubber products, the smooth surface forming body used as a mating material for rubber products is given properties that are compatible with the rubber products and do not generate a large amount of heat in the rubber products. I try to do that.

The inter-intervening network structure according to the present invention is made of polytetrafluoroethylene resin (PTFE), which is formed by maintaining appropriate pressure during pressure molding, temperature during firing, atmospheric pressure during firing, or press pressure. It means a three-dimensional network structure in which heat-resistant resins other than PTFE are entangled with each other in a network shape by pressurized flow or thermal flow. FIG. 1 shows an example of the mutually intervening network structure of the smooth surface forming body of the present invention. In the figure, 1 is inorganic powder, 2 is PTFE, 3 is heat-resistant resin excluding PTFE, and 4
is a void. Reticulated PTFE as seen in Figure 1
2 and the network-like heat-resistant resin 3 excluding PTFE form a three-dimensional network while incorporating the inorganic powder, and the network formed by the bond between the PTFE 2 and the network of the heat-resistant resin 3 excluding PTFE are highly and mutually entwined. It has a network structure of mutual intervention.

As mentioned above, the smooth surface forming body has a mutually intervening network structure, and the PT
Voids exist at the interface between FE and heat-resistant resins other than PTFE. This void improves compatibility with rubber products,
It has the effect of significantly reducing the heat generated by friction with rubber products (heat reduction function). In addition, when rubber collides with a mating material, these voids absorb the impact energy before the rubber is extremely deformed to the point of quasi-crystallization, and play a role in mitigating damage to the surface of the rubber product (destruction). relaxation function). The ratio of voids (porosity) is preferably maintained within a range of 0.5 to 30%. If this porosity falls outside of the above range, the heat generation reduction function and fracture mitigation function described above will decrease.

The optimum ratio of the above-mentioned porosity varies depending on the rubber hardness, the chemical structure of the rubber, and the compounding of the rubber. In the case of PVC-based, butadiene-based, and SBR-based rubbers, a porosity of 15 to 30% makes it possible to reduce wear the most. In addition, in the case of urethane rubber, it is 20 to 30%, and in the case of NR rubber, it is 0%.
．． The wear reduction effect is greatest in the range of 5 to 15%.

Inorganic powders used in the smooth surface forming body of the present invention include alumina, silica, zirconia, titania, calcia, metal oxides such as copper oxide, iron oxide, molybdenum oxide, and magnesium oxide, silicon nitride, aluminum nitride, and titanium nitride. Metal nitrides, metal carbides such as silicon carbide and aluminum carbide, pure metals such as copper, aluminum, gold, silver, titanium, iron, molybdenum, vanadium, nickel, and tungsten, and alloys such as stainless steel, brass, aluminum alloys, and magnesium alloys. , metal sulfides such as silicon sulfide, and graphite powders can be used. The average particle size of the inorganic powder is 1-2
Preferably, it is 0 μm. Further, alumina and zirconia are particularly desirable, and those having a spherical shape are suitable, and those having a sphericity of 0.9 or more are particularly suitable.

Heat-resistant resins other than PTFE include polyphenylene sulfide (PPS), polyamideimide, polyimide, polyether ether ketone (PEEK), phenol resin, epoxy resin, polyether sulfon, ester resin, fluororesin other than PTFE, etc. Tetrafluoroethylene-perfluoroalkyl copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polymonochlorotrifluoroethylene, ethylene-tetrafluoroethylene copolymer, etc. can be used, but polyphenylene sulfide, polyamideimide, etc. , PEEK are most suitable. In addition, the weight ratio of tetrafluoroethylene copolymer (tetrafluoroethylene-perfluoroalkyl copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, etc.) to tetrafluoroethylene resin (PTFE) is 2%~4
By adding 0%, the formation of a PTFE network is assisted, making it possible to improve the strength of the smooth surface forming body.

Furthermore, molding may be used to manufacture the smooth surface formed body, but
There are no particular restrictions on the molding method; hot press, injection molding,
Any method such as extrusion molding or rubber press can be used. Since it is important to provide voids inside the smooth surface forming body, the appropriate molding pressure for the smooth surface forming body is 50~50 for a mixture of PTFE, inorganic powder, and heat-resistant resin excluding PTFE.
Preferably the pressure range is 800 kg/ant, 1
The most suitable molding pressure is 50 to 350 kg/caf. In addition, the most economical and productive processing method is to manufacture tablets using the above method and then sinter them under a load that prevents deformation such as warping within the flowable temperature range of PTFE and heat-resistant resins other than PTFE. It's a method.

In addition, when processing with hot press, the pressurizing pressure is 30 kg/
Must be kept below cut.

The above-mentioned sliding surface forming bodies are materials for the landing section of aircraft, track materials for linear motor cars, etc., in other words, materials for runways for high-speed moving vehicles, brake shoes, pistons, members for O-rings of sliding parts, etc. Can be used for

This material can be processed into various shapes by molding or cutting after molding, and parts such as pistons are processed into the desired shape. In addition, for track materials of linear motor cars and landing parts of aircraft, runways such as tracks and runways are constructed using sliding surface forming bodies by methods such as gluing, bolting, fitting, and integral construction with concrete. However, there are no restrictions on the construction method as long as sufficient adhesion to the structure is achieved. In this case, the sliding surface forming body is arranged at the initial contact point of the track with the rubber tires of the high-speed moving body. Thereby, it is possible to prevent the rubber tires and the sliding surface forming body from coming into contact with each other only at the moment when the high-speed moving body lands on the ground, thereby preventing significant wear, and then bringing them into contact with a running track having normal characteristics. Further, as methods for improving the strength of this smooth surface forming body, there are methods such as backing with a reinforcing plate such as a glass reinforced epoxy plate or metal plate or a rod, fiber reinforcement, impregnation with an epoxy resin, etc.

〔Effect of the invention〕

As explained above, according to the smooth surface forming body of the present invention, it is possible to reduce the frictional wear of rubber products, so that the range of application of rubber can be widened.

Further, according to the running track for high-speed moving objects using the sliding surface forming body of the present invention, it is possible to prevent significant wear of rubber tires used for high-speed moving objects such as linear motor cars and airplanes, and also to absorb shock. This has the effect that the road surface can be protected.

〔Example〕

Example I PTFE powder, alumina powder with an average particle size of 4 μm, and crosslinked PPS are mixed in a weight ratio of 5:10:3, and an organic dispersion medium containing toluene as a main ingredient is added to form a slurry and uniformly dispersed for 30 minutes. The organic dispersion medium was filtered from this slurry, and the mixed powder was removed through a drying process.
Apply pressure of 0kg/Crl, 100ma+X 100
Tablets of mmX I Os were obtained. This tablet was placed in an electric furnace at 380°C at 100g/cn? A smooth-surface molded body was obtained by sintering and hardening under a load of . The rubber tire was subjected to an abrasion test using a friction and abrasion tester (Japanese Patent Application No. 1-32251) by bringing this smooth surface forming body into contact with a rotating tire under a predetermined load. For comparison, a similar test was conducted on concrete. The results are shown in Table 1.

Note) ■Wear conditions Test count: 100 times Tire diameter: 2
50mmφ Tire width 20mm Tire peripheral speed 70km/h Load 2. 5kg/CTl ■Frictional resistance force: The maximum resistance force during the test was detected by a load cell.

■Heating temperature: The tire surface temperature at the end of 100 wear tests was measured, and the highest temperature was taken as the heating temperature.

As mentioned above, the smooth surface forming body was significantly effective in reducing friction and preventing rubber wear compared to concrete, and in particular, the amount of tire wear was reduced to less than one-thirtieth, which was a great effect in reducing wear.

Example 2 PTFE powder, alumina powder with an average particle size of 2 μm, P
7:1 PS powder and polyamideimide powder
Dry mixed at 0:3:2 (weight ratio), 100 kg/
After pressing at a pressure of c-, 60k for 3 minutes at 360℃
Hot pressing was carried out under a load condition of g/cd, and the product was rapidly cooled to 140° C. to obtain a smooth-surfaced product having a thickness of 2flI11.

This smooth surface forming body was attached as a 2 mm thick spacer so as to serve as a mating material for the airtight O-ring of the movable part, and frictional resistance and wear of the O-ring were examined. For comparison, a similar test was conducted using a 2m+n thick SUS 304 spacer having the same shape as above. The results are shown in Table 2.

Table 2 Note) Test conditions Diameter of 01J ring 60 stroke Thickness of 0 ring 1fflI! lφ Rotation speed 2 Or pm Rotation conditions Rotate 10 times and stop for 1 minute. Repeat this for 10 psi.

Compared to SUS 304, the smooth surface material reduces both the frictional resistance and the amount of wear on the O-ring, and shows excellent lubrication performance with no burning of rubber to the mating material.

Ta.

Figures 2 (1) to (3) show the shapes of the smooth surface forming bodies. Second
FIG. 1 shows a plate-like smooth surface forming body 10. FIG. Second
In FIG. 2, a convex portion 10A and a concave portion 10B are formed on the side surface of the plate-like smooth surface forming body 10. The convex portions 10A and recesses 10B of adjacent plate-like smooth surface forming bodies 10 are fitted together to arrange the plate-like smooth surface forming bodies. In FIG. 2(3), slopes 12A and 12B are formed on the side surfaces of the plate-shaped smooth surface forming body 10.

Slope 12A and slope 12B of adjacent plate-shaped smooth surface forming body 10
The plate-like smooth surface forming bodies are arranged by bringing them into contact with each other.

FIGS. 3(1) to 3(4) show the reinforced smooth surface forming body 10. 3(1) shows a reinforcing plate 12 made of metal, FRP, etc. bonded together using an adhesive layer 14, and FIG. 3(2) shows a reinforcing plate 12 and a plurality of reinforcing rods 16 made of the same material bonded together.

In FIG. 3(3), a reinforcing member 18 such as glass cloth or wire mesh is embedded in the smooth surface forming body 10. In FIG. 3(4), the smooth surface forming body 10 and the resin-impregnated layer 20 are integrally formed.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the mutually intervening network structure of the smooth surface forming body of the present invention, FIGS. 2 (1) to (3) are perspective views of the smooth surface forming body used for a running track, and FIG. 3 (1) - (4) are perspective views for explaining a method of reinforcing the smooth surface forming body. 1... Inorganic powder, 2... PTFE. 3...Heat-resistant resin 10...Smooth surface forming body.

Claims (12)

[Claims] (1) The main ingredients are tetrafluoroethylene resin, inorganic powder, and heat-resistant resin other than tetrafluoroethylene resin, and the net-like tetrafluoroethylene resin and the net-like heat-resistant resin are entangled with each other by at least pressure or heat. A smooth surface forming body with an interwoven network structure containing Aikatsu inorganic powder. (2) The smooth surface forming body according to claim (1), wherein the inorganic powder is made of at least one selected from the group of metal oxides, metal nitrides, metal carbides, metal sulfides, pure metals, alloys, and graphite. . (3) Smooth surface formation according to claim (2), wherein the metal oxide is at least one selected from the group of alumina, silica, zirconia, titania, calcia, copper oxide, iron oxide, molybdenum oxide, and magnesium oxide. body. (4) The smooth surface forming body according to claim (2), wherein the metal nitride comprises at least one selected from the group of silicon nitride, aluminum nitride, and titanium nitride. (5) Claim (2) wherein the metal carbide is made of silicon carbide.
) The smooth surface forming body described in ). (6) Claim (2) wherein the pure metal is at least one selected from the group consisting of copper, aluminum, gold, silver, titanium, iron, molybdenum, vanadium, nickel, and tungsten.
) The smooth surface forming body described in ). (7) The smooth surface forming body according to claim (2), wherein the alloy is at least one selected from the group of stainless steel, brass, aluminum alloy, and magnesium alloy. (8) The smooth surface forming body according to any one of claims (1) to (7), wherein the inorganic powder has an average particle size in a range of 1 to 20 μm. (9) the heat-resistant resin is polyphenylene sulfide;
According to any one of claims (1) to (8), consisting of at least one selected from the group of polyamideimide, polyimide, polyethersulfone, polyetheretherketone, epoxy resin, phenol resin, and ester resin. smooth surface formation. (10) The smooth surface forming body according to any one of claims (1) to (9), wherein the porosity is in the range of 0.5% to 30.0%. (11) A running track for a high-speed moving body, wherein the smooth surface forming body according to any one of claims (1) to (10) is disposed at an initial contact portion with a rubber tire of the high-speed moving body. (12) A method of using a smooth surface forming body, comprising using the smooth surface forming body according to any one of claims (1) to (10) as a material for a runway for a high-speed moving body.