JPH08170655A - Synchronous ring for speed changer and manufacture thereof - Google Patents

Abstract

PURPOSE: To provide a synchronous ring for a speed changer excellent in wearing resistance, mechanical characteristic and corrosion resistance and to provide a method of manufacturing this synchronous ring for the speed changer. CONSTITUTION: A synchronous ring for a speed changer contains a copper system sintered alloy, and this sintered alloy has a composition of uniformly dispersing a hard grain in the inside of old powder grain containing a base of copper alloy, 0.2 tensile bearing force of 400MPa or more and Rockwell B hardness of 70 or more. The synchronous ring thus obtained can be formed by heating a molded material of grain dispersing copper alloy powder of uniformly dispersing hard grains in a base of the copper alloy and by using a sintered alloy sintered in true density ratio of 95% or more by hot working.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission synchronizing ring (synchronizer ring) used in an MT (manual transmission) of an automobile and the like, and particularly to a sulfidizing corrosion resistance, wear resistance, and Seizure resistance, friction characteristics in lubricating oil,
It relates to improvement of strength, toughness and hardness.

[0002]

2. Description of the Related Art In recent years, since high torque is applied to a transmission for an automobile which has been improved in performance, the materials of parts used for the transmission are improved and the design is reviewed. . Particularly, in MT, a multi-type synchronizer ring such as a double type or a triple type is adopted in order to improve the synchronizing capacity. However, since the multi-type synchronization ring has a large number of parts and a complicated mechanism, it is difficult to satisfy the demand for size reduction and weight reduction.

Therefore, in a single type synchronizing ring, a design is being considered which realizes a performance equivalent to that of the multi type by increasing the friction coefficient μ of the taper cone portion on the inner periphery of the synchronizing ring to improve the synchro capacity. For example, there has been proposed a synchronizing ring in which a liner of a friction sliding member such as a thermal spray material, a paper material, and a resin material is attached to the inner peripheral portion. As an example thereof, Japanese Patent Publication No. 6-79835, "Method for producing synchronizer ring" discloses the use of a paper material impregnated with a resin. Also known is a method of improving the coefficient of friction by adding hard particles to the base material of an iron-based, Al-Si-based, aluminum bronze-based, or high-strength brass-based alloy without using such a liner. ing. An example of an alloy containing such hard particles is disclosed in JP-A-1-25274.
No. 4 “Cu-based sintered alloy transmission synchronizing ring” and Japanese Patent Application Laid-Open No. 5-331504, “Friction sliding member”.

[0004]

However, the conventional single type transmission synchronizing ring has the following problems (1) to (5).

(1) Since the friction surface of the inner peripheral tapered cone portion of the synchronizing ring does not have a friction coefficient μ exceeding 0.2 when sliding on the tapered cone portion of the mating steel material in the lubricating oil, It is difficult to achieve the same characteristics as a synchronization ring with a single type synchronization ring.

(2) Under extremely severe conditions of use, seizure or abrasion damage occurs, and there is a problem that the amount of wear increases or the mating material is attacked during long-term use.

(3) When a copper-based alloy is used as the friction sliding member, sulfidation corrosion is caused by sulfur which is an extreme pressure additive contained in the lubricating oil, and durability is impaired.

(4) When a sintered alloy is used as the friction material, the hard particles added to improve the coefficient of friction are simply mixed with the mother alloy powder to carry out molding and sintering, so that it can be seen microscopically. For example, hard particles do not form a reaction layer with the mother alloy even after sintering, and exist with a gap between the former powder grain boundaries of the mother alloy (particularly the triple points of the grain boundaries). . Therefore, in the friction material of such a sintered alloy, hard particles fall off from the old powder grain boundaries during sliding to become abrasion powder, and seizure or friction damage occurs by attacking the mating material or the friction material itself. There is a problem.

(5) If a liner of friction sliding material made of paper or resin is used on the inner peripheral portion of the synchronizing ring or a surface treatment such as thermal spraying is applied to obtain a high μ value, the cost of the synchronizing ring is increased. It causes problems in terms of economy.

In view of the above problems in the prior art, the present invention has excellent sulfidation corrosion resistance even in an oil containing sulfur as a component of an extreme pressure additive, and
A synchronizing ring for a transmission including a copper-based sintered friction member that has excellent wear resistance and seizure resistance in oil and that can stably maintain a high friction coefficient exceeding 0.2, and a method for manufacturing the same. The purpose is to do.

[0011]

SUMMARY OF THE INVENTION A transmission synchronizing ring according to one aspect of the present invention includes a copper-based sintered alloy, wherein the sintered alloy includes hard particles inside old powder particles including a base of the copper alloy. Uniformly dispersed structure and 0.2 above 400 MPa
It is characterized by having a% tensile strength and a Rockwell B hardness of 70 or more.

The taper cone friction surface of the inner peripheral portion of the synchronizing ring preferably has a friction coefficient of 0.2 or more when synchronized with the taper cone portion of the mating steel material in the lubricating oil.

Hard particles have a maximum particle size of 30 μm or less and 1
It preferably has an average particle size of 5 μm or less.

The copper-based sintered alloy is, as hard particles, 10 to 10.
It is preferable to include at least one of iron-based intermetallic compound particles and Mo particles within a range of 50% by weight.

As the iron-based intermetallic compound particles, FeM
It may include at least one selected from o, FeCr, FeTi, FeW, and FeB.

The copper alloy base is preferably 5 to 40% by weight.
Within the range, it contains at least one of Zn and Ni and the balance is copper, and has excellent sulfide corrosion resistance.

The copper alloy base is preferably 3 to 20% by weight.
Of Sn may be further included. The copper alloy substrate is preferably
1-5 wt% Si, 1-5 wt% Al, and 0.
It may further comprise at least one of 5 to 3 wt% Pb.

The copper alloy base is preferably less than 5% by weight.
Graphite, MoS within the range₂ , CaFe ₂ , WS₂ ,and
Further comprising at least one solid lubricant of BN
obtain.

According to another aspect of the present invention, there is provided a method for manufacturing a synchronizing ring for a transmission, comprising preparing a particle-dispersed copper alloy powder in which hard particles are uniformly dispersed in a copper alloy matrix, and the particle-dispersed copper alloy is prepared. The method is characterized by including a step of forming and heating a powder compact of powder, and solidifying the heated powder compact to a true density ratio of 90% or more by hot plastic working.

In preparing the particle-dispersed copper alloy powder,
Preferably, a mixed powder containing copper alloy powder and hard particles is prepared and at least one of a mechanical alloying method (mechanical alloying method), a mechanical mixing method (mechanical cladding method), and a granulation method is added to the mixed powder. By performing one mixing and pulverizing process, the hard particles are pulverized so as to have a maximum particle size of 30 μm or less and an average particle size of 15 μm or less and are dispersed in the copper alloy powder matrix.

The particle-dispersed copper alloy powder is preferably 5
It has an average particle size in the range of 0 to 250 μm.

The particle-dispersed copper alloy powder is preferably
50 g in an orifice tube with a diameter of 2.5 mm
It has the fluidity to flow down in 30 seconds or less.

The powder dispersion of the particle-dispersed copper alloy preferably has a true density ratio of 70% or more and is 600 in an atmosphere containing at least one of an inert gas and a reducing gas.
5 above ℃ and below the melting start temperature of the copper alloy substrate
Immediately after being made into a temporary sintered body by heating for more than a minute, hot forging in a closed die is made into a ring-shaped copper-based sintered alloy having a true density ratio of 95% or more, and at the same time, a ring-shaped body. A spline meshing tooth portion is formed on the outer peripheral surface of the.

The pre-sintered body may be cooled once for transportation and then heated again to be hot forged.

The pre-sintered body may be formed into a copper-based sintered alloy having a true density ratio of 95% or more by hot extrusion. The copper-based sintered alloy obtained by hot extrusion can be processed into a synchronizing ring by machining, but is preferably formed by hot forging.

[0026]

The transmission synchronizing ring according to the present invention has a structure in which fine hard particles are uniformly dispersed in the old powder particles made of a copper alloy of a sintered material base (matrix), and the tapered cone of the inner peripheral portion of the ring. The friction surface is, for example, JIS SCM42
Has a friction coefficient of 0.2 or more when synchronized in the oil in the transmission with the taper cone part of the counterpart material made of carburized steel, and has a 0.2% tensile strength of 400 MPa or more and a Rockwell B hardness of 70 or more. It is an important feature to have. Therefore, by using the synchronizing ring according to the present invention in an MT device, it is possible to replace a multi-type synchronizing ring having a large number of parts and a complicated mechanism with an inexpensive single-type synchronizing ring having a simple structure.

In order to obtain a synchronizing ring made of a sintered material having such a structure, friction-sliding characteristics, and mechanical characteristics, a fine hard metal is previously prepared inside a copper alloy powder to be molded and sintered. The present inventors have found that it is effective to use a particle-dispersed copper alloy powder in which particles are uniformly dispersed as a raw material powder for sintering. Further, it relates to the kind, size, addition amount, and dispersibility of the hard particles suitable for the synchronizing ring, the composition of the copper alloy base material, and the fluidity, molding, sintering, and hot working of the particle dispersion type copper alloy powder. Appropriate conditions have been found by various experiments and studies. The reason for the proper range of these conditions is explained in detail below.

First, the hard particles are finely and uniformly dispersed in the sliding surface of the sintered friction material to suppress the occurrence of adhesion with the mating material during friction sliding at room temperature or high temperature, and to improve seizure resistance. In addition to the improvement, it can play a role of directly contacting the surface of the base material of the mating material to improve the friction coefficient. However, in order for the hard particles to play such a role, it is necessary that the hard particles do not fall off from the sliding surface substrate of the sintered material during friction sliding.

Therefore, in order to exert the excellent effect on the hard particles, the inventors of the present invention used the sintered friction material as shown in FIG.
It was thought that it would be ideal to have a tissue structure as shown in the schematic diagram of. That is, it is desirable that the fine hard particles are uniformly dispersed inside the old powder particles of the copper alloy base material having a predetermined composition, and that the hard particles are firmly bonded and fixed to the copper alloy base material. In the sintered friction material having such a structural structure, the hard particles are prevented from falling off during friction sliding, and a stable friction sliding state can be obtained for a long period of time. That is, excellent durability can be realized in the friction sliding performance of the synchronizing ring according to the present invention.

In order to realize the structure as shown in FIG. 1 (A), the present inventors have made a particle dispersion in which fine hard particles are uniformly dispersed in advance in the base material of the copper alloy powder. It was considered necessary to shape and sinter the mold copper alloy powder. That is, using the hard particle-dispersed copper alloy powder, as shown in FIG.
Obtaining a synchronizing ring having an organizational structure as shown in (A) is the most important feature of the present invention.

As a result of repeating various experiments and studies, as a method for economically preparing a particle-dispersed copper alloy powder in which fine hard particles are uniformly dispersed, the following mechanical mixing and pulverizing treatment of the powder is carried out. It has been found to be effective to apply. That is, by applying mechanical mixing and pulverizing treatment of powders, which is represented by the mechanical alloying method, the mechanical cladding method, and the granulation method, for the first time, hard particles such as intermetallic compounds and metal powders can be finely divided. It has been found that these fine hard particles can be uniformly dispersed in the copper alloy powder matrix at the same time as pulverizing into fine powder.

These mechanical grinding and mixing treatments are carried out by a dry method rather than a wet method such as the conventional grinding and mixing by a ball mill. Also, if desired, PCA
Excessive agglomeration of the powder can be prevented by adding a small amount of stearic acid or alcohol as a (process control agent). An attritor or a ball mill can be preferably used as the processing device. Attritors are suitable for high-speed processing because they have excellent pulverization efficiency.
The ball mill requires a long time treatment, but the atmosphere control is easy, and it is relatively economical if the input energy is properly designed.

As another method, the hard particles can be stirred and dispersed in a molten copper alloy, and the powder can be sprayed by an atomizing method to prepare a powder in which the hard particles are dispersed. However, since the hard particles cannot be finely dispersed by the atomization method, it is necessary to prepare fine hard particles in advance and add them to the molten copper alloy. In that case, a sufficient stirring step is required to prevent the segregation and agglomeration of the hard particles in the molten metal, which significantly increases the manufacturing cost of the powder and causes a problem in economic efficiency.
Further, when a large amount of hard particles is added, there is also a problem that the hard particles are clogged in the nozzle during spraying of the copper alloy melt containing the hard particles. Therefore, in the production of the copper-based sintered material of the present invention, it is desirable to use a mechanical powder mixing and pulverizing process.

Regarding the desirable size and amount of hard particles to be added, the inventors of the present invention evaluated various treatment conditions when performing the above-mentioned mechanical mixing and pulverizing treatment on a copper-based powder having a predetermined composition. As a result, in order to stably secure a high friction coefficient without deteriorating mechanical properties, it was found that there is an appropriate range of the size and addition amount of the hard particles as follows. That is, by including hard particles having a maximum particle size of 30 μm or less and an average particle size of 15 μm or less in the sintered material in the range of 10 to 50% by weight, the hard particles are finely and uniformly formed into an alloy of the base material. It was confirmed that a stable high friction coefficient can be ensured without being dispersed in the powder and deteriorating the mechanical properties of the sintered friction material.

On the other hand, if the content of the hard particles in the entire sintered sliding member is less than 10% by weight, the content of the hard particles in the oil is higher than 0.2 when sliding with a steel material such as SCM420 as a mating material. The coefficient of friction cannot be obtained, and the effect of improving wear resistance cannot be obtained. Also, the hard particles are 3
If the maximum particle size exceeds 0 μm or the average particle size exceeds 15 μm, or if the content thereof exceeds 50% by weight of the entire sintered sliding member, the hard particles are likely to be the starting point of cracking, and as a result, as described later. Even if the copper-based sintered metal is subjected to various hot plastic workings, its strength and toughness are reduced. Furthermore, addition of hard particles in excess of 50% by weight is not preferable from the viewpoint of opponent attacking property, because it causes severe abrasion of the opponent material.

The hard particles preferably include at least one of Mo particles and iron-based intermetallic compound particles. As the iron-based intermetallic compound, FeMo, FeCr, FeT
at least one selected from i, FeW, and FeB
It is desirable to include one. Because, these iron-based intermetallic compounds have sufficient hardness and are suitable as hard particles, and are brittle and therefore excellent in pulverizability, and hard during mechanical mixing and pulverization treatment used in the present invention. This is because it is easy to make the particles finer. In addition,
In addition to intermetallic compounds, metal oxides such as Al ₂ O ₃ , SiO ₂ , and ZrO and ceramics such as SiC and AlN also have the effect of improving the friction coefficient, but these particles are more effective than iron-based intermetallic compounds. Since the machinability of the sintered material is deteriorated, there is a problem in terms of economy. Therefore, the iron-based intermetallic compound is more preferable as the hard particles.

In summary, regarding the production of the sintered material used for the synchronizing ring of the present invention, the mixed powder of the copper alloy powder having the predetermined composition and the hard particles is mechanically mixed and pulverized to obtain a hard mixture. At the same time as pulverizing the particles into fine particles having a maximum particle size of 30 μm or less and an average particle size of 15 μm or less,
The fine hard particles are uniformly dispersed in the copper alloy powder (in the powder base). By molding and sintering such a particle-dispersed copper alloy powder and subjecting it to plastic processing such as hot forging or hot extrusion, a reaction layer is formed at the interface between the copper alloy matrix and the hard particles to form hard particles. Can be firmly fixed in the copper alloy base material, and mechanical properties sufficiently usable as a synchronizing ring can be obtained. That is, the hard particles in the synchronizing ring do not fall off from the sliding surface substrate of the sintered alloy during friction sliding, seizure and wear damage are suppressed, and stable friction exceeding 0.2 in lubricating oil is achieved. The coefficient can be obtained, and further, 0.2% tensile proof stress of 400 MPa or more and Rockwell B hardness of 70 or more can be obtained.

Incidentally, since the hard particles are not pulverized by the conventional simple powder mixing method by the powder metallurgy method, FIG.
As shown in the schematic structural diagram of No. 1, the hard particles have a particle size as they are mixed with the copper alloy powder.
Therefore, when fine hard particles were prepared in advance and used as a starting material together with the copper alloy powder, the hard particles fell off due to the aggregation or segregation of the hard particles, the wear resistance of the sintered material was lowered, and the mechanical properties A drop has occurred. Further, in the conventional simple powder mixing method, the hard particles do not react with the copper alloy powder or disperse inside the copper alloy powder. Therefore, if such a mixed powder produced by the conventional powder metallurgy method is molded and sintered, coarse hard particles exist in the old powder grain boundaries (particularly the triple boundaries of the grain boundaries) of the copper alloy matrix, and the hard particles and the old hard grains are combined. A gap is formed in at least a part of the interface of the copper alloy powder. As a result, during frictional sliding, hard particles fall off from the base material and become abrasion powder, which instead causes a problem of attacking the mating material or the sintered material itself or inducing a seizure phenomenon. Also,
When stress is applied to the sintered friction material, if the hard particles are present in the old powder grain boundaries of the base material, they will become the starting points and propagation paths of cracks, thus reducing the mechanical properties of the sintered body. Causes the problem of

Next, the alloy composition of the matrix of the copper-based sintered alloy used in the synchronizing ring of the present invention,
The conditions concerning the structure and the true density ratio of the sintered alloy will be explained.

Zn has a deoxidizing effect, and if it is added to the matrix, a stable ZnO layer can be uniformly formed on the entire surface of the sintered matrix. Since this zinc oxide layer can act as a protective film, it can inhibit the reaction of S with copper ions in the atmosphere containing sulfur, and suppress the generation of copper sulfide that causes sulfide corrosion. On the other hand, if the amount of Zn added to the copper alloy base material increases, the β'phase appears, and as a result, the alloy base material becomes hard and brittle, which induces strength reduction and cold workability remarkably deteriorates. Cause

The amount of Zn required to suppress sulfide corrosion is 5
In order to suppress the embrittlement phenomenon of the matrix, it is not preferable to add Zn in excess of 40% by weight. That is, the preferable addition amount of Zn in the alloy base is 5 to
It is 40% by weight.

Like Zn, Ni has the effect of suppressing the formation of copper sulfide and improves the hardness of the alloy base,
Further, an intermetallic compound with nickel (nickel silicide), which will be described later, is made to exist as fine spherical particles, and the nickel silicide particles generate resistance during friction sliding, thereby improving the friction coefficient. In order to produce such a preferable effect, it is necessary to add 5% by weight or more of Ni in the matrix. On the other hand, if the amount of Ni added exceeds 40% by weight, the alloy base becomes brittle, and as a result, there arises a problem that workability in cold and hot is deteriorated. That is, the preferable addition amount of Ni in the alloy base is 5 to 40% by weight.
Is.

The total content of Zn and Ni in the alloy base is 4
If the amount exceeds 0% by weight, the sintered body is significantly hardened to induce a decrease in toughness, which causes a problem that the workability of the sintered member in cold and hot is deteriorated. That is, the preferable total content of Zn and Ni in the alloy base is 40% by weight or less.

The addition of Sn into the base material has the effect of improving the high temperature hardness and toughness of the base material, and also has the effect of improving the seizure resistance at high temperatures. Therefore, when the friction sliding condition is severe, it is preferable to add Sn to the alloy base. If the addition amount of Sn is less than 3% by weight, no preferable effect is produced, and if it exceeds 20% by weight, a hard and brittle phase precipitates in the base material, resulting in deterioration of strength and toughness. That is, the preferable addition amount of Sn in the alloy base is 3 to 20% by weight.

Al reacts with Cu to form an intermetallic compound such as Cu ₆ Al ₄ to improve the hardness of the alloy and to form resistance particles at the time of friction sliding, so that the effect of improving the friction coefficient is obtained. Occurs. However, addition of less than 1% by weight of Al does not provide sufficient improvement in hardness and friction resistance. On the other hand, if Al is added in an amount of more than 5% by weight, embrittlement of the alloy is induced to deteriorate cold workability, a strong oxide (Al ₂ O ₃ ) layer is formed, and sinterability is improved. This causes problems such as hindering or reducing the machinability of the alloy base. That is, the preferable amount of Al added to the alloy base is 1 to 5% by weight.

As described above, Si forms a fine spherical intermetallic compound (nickel silicide) together with Ni, and this intermetallic compound acts as resistance during friction sliding to improve the friction coefficient. If less than 1% by weight of Si is added, a sufficient effect for improving the friction coefficient cannot be obtained, and if the amount of Si added exceeds 5% by weight, the workability of the alloy base in hot and cold is deteriorated. . That is, the preferable amount of Si added to the alloy base is 1 to 5% by weight.

Pb is evenly present between the α phase grain boundaries and dendrites of the copper alloy matrix, and has the effect of improving the machinability of the matrix and the lubricity during friction sliding. In order to obtain such an effect, it is necessary to add 0.5% by weight or more of Pb. However, if Pb is added in an amount of more than 3% by weight, segregation occurs inside the alloy base material and mechanical properties are deteriorated. Causes the problem. That is, the preferable addition amount of Pb in the alloy base is 0.5 to 3% by weight.

The solid lubricant reduces the aggressiveness of the sintered member against the mating material under more severe friction and sliding conditions, and even when the friction and sliding conditions such as the sliding speed and the pressure change, the solid lubricant can be used in the oil. It has an effect of maintaining a stable friction coefficient of 0.2 or more, and also has an effect of suppressing vibration and chatter during sliding by improving lubricity between sliding surfaces. As a solid lubricating component having such an effect in a copper-based sintered powder member, graphite, which is economically preferable, M
_{oS 2, CaF 2, WS 2} , and BN can be used. At this time, graphite, MoS ₂ , CaF ₂ , WS
It is preferable to add at least one of ₂ and BN in a range of 5% by weight or less. If the amount of the solid lubricant added exceeds 5% by weight, the strength and toughness of the sintered body will be significantly reduced, which is not preferable.

The synchronizing ring according to the present invention requires 0.2% tensile yield strength of 400 MPa or more. In order to realize this tensile yield strength, the above-mentioned alloy composition conditions are satisfied and the voids in the sintered alloy are satisfied. It is also desirable to control the amount. That is, when the true density ratio of the sintered alloy is less than 95%, the holes in the sintered alloy become connecting holes,
The strength of the sintered alloy deteriorates and exceeds 0.4 MPa.
It becomes difficult to obtain 2% tensile strength. Therefore,
The true density ratio of the copper-based sintered alloy used for the synchronizing ring of the present invention is desired to be 95% or more. As a specific method for setting the true density ratio of the sintered alloy to 95% or more, hot plastic working such as hot forging method and hot extrusion method described later can be effectively used.

Next, the relationship between the fluidity of the particle-dispersed copper alloy powder produced as described above and the mechanical properties of the sintered material will be described.

In general, the powder is powdered in a mold and then pressed by upper and lower punches. However, at this time, if pressure is applied in a state where the powder is not uniformly filled in the mold, the density becomes uneven inside the molded body, resulting in chipping or cracking at the end, or sintering. Later, there arises a problem that the powder compact warps. In order to suppress these problems, it is necessary to uniformly supply and fill the powder from the end to the inside of the mold. The flowability of the powder is the major factor governing the homogeneity in filling the powder in such a mold.

By the way, since the powder is a pseudo fluid, it is possible to obtain excellent fluidity by adjusting the particle size of the powder. Therefore, as a result of repeated experiments and studies by the present inventors, in order to be able to use a molding process in which powder can be uniformly filled in a mold and economically mass-produced, a diameter of 2.5 mm It has been found that a powder flowability of less than 30 seconds is required for 50 g of powder to finish flowing in the orifice tube. That is, the fluidity is 30 seconds /
If a powder exceeding 50 g is used, it takes a long time to uniformly fill the mold, resulting in an economic problem that productivity is impaired. In addition, since such a powder having poor fluidity may not be uniformly filled in the mold,
The problems of chipping and cracking of the molded body as described above also occur.

Therefore, in order to realize preferable fluidity, the copper-based alloy powder has an average particle size of 50 μm to 250 μm.
It has also been found desirable to be in the range of m. That is, when the average particle size of the powder is less than 50 μm, the fluidity is hindered, and conversely, when the average particle size exceeds 250 μm, the moldability of the powder is hindered. Chips and cracks occur in the parts.

Using the particle-dispersed copper alloy powder having the structure and characteristics as described above, the synchronization according to the present invention can be performed by using any one of the steps (a) to (f) shown in FIG. The ring can be manufactured.

First, the density of the powder compact formed from the particle-dispersed copper alloy powder is preferably 70% or more in true density ratio. This is because when the true density ratio is less than 70%, sufficient compact strength cannot be obtained, so that chipping or cracking is likely to occur in the conveying process until the powder compact is sintered. This is because it causes a decrease. Therefore, in order for the powder compact to have sufficient handleability in the mass production process, the true density ratio should be 7
It is preferably 0% or more.

Next, the powder compact is heated to a predetermined temperature in a predetermined atmosphere, and the heating has two purposes.
One purpose is provisional sintering for obtaining strength to prevent cracking and chipping of the green compact during the conveying process until the hot plastic working in the subsequent step. Another purpose is to heat the pre-sintered body so that it can be easily plastically deformed, and firmly bond the powder particles to each other to improve the mechanical properties of the sintered alloy.

First, as a heating condition necessary for obtaining a pre-sintered body, a sintering temperature of 600 ° C. or higher is required because a sintering phenomenon hardly progresses at a temperature of lower than 600 ° C. On the other hand, if the sintering temperature exceeds the melting start temperature of the copper alloy, a liquid phase appears and the sintered body shrinks, which causes a problem that the dimensional accuracy of the sintered body deteriorates. Therefore, it is also desired that the sintering temperature is equal to or lower than the melting start temperature of the copper alloy. Further, in order to obtain mechanical properties such that cracks and chips do not occur during transportation of the pre-sintered body, 600 ° C.
It is desired that the heating is performed for 5 minutes or more at a temperature not lower than the melting start temperature of the copper alloy. When the heating time is less than 5 minutes, the strength of the obtained temporary sintered body is not sufficient, and thus the handling property is poor, and the temporary sintered body may be cracked or chipped during the transportation process.

Regarding the heating conditions desired to achieve the purpose of hot plastic working of the pre-sintered body, since the plastic deformation resistance of the pre-sintered body is large at a temperature of less than 600 ° C., hot forging and hot working It is difficult to deform the pre-sintered body by plastic working such as extrusion to bond the powder particles to each other sufficiently firmly. Further, if the deformation resistance of the pre-sintered body is too large, a large facility for applying a high pressure is required to densify the pre-sintered body, which causes an economical problem. Furthermore, under high pressure, the life of the mold and extrusion die is shortened. Therefore, even when hot plastic working is performed on the pre-sintered body, a heating temperature of 600 ° C. or higher is desired. On the other hand, if the temperature of hot plastic working exceeds the melting start temperature of the copper alloy, the liquid phase appears as described above and the dimensional accuracy decreases due to shrinkage of the sintered body, so the hot plastic working temperature is It is desired that the temperature is not higher than the melting start temperature of. Further, regarding the heating and holding time, it is desired that the heating and holding time is 5 minutes or more in order to bond the powder particles to each other sufficiently firmly.

In FIG. 2, regarding heating for temporarily sintering the powder compact, an oxide film is formed on the powder surface when the atmosphere is not an atmosphere of an inert gas or a reducing gas, and the final sintered body is obtained. Causes a problem that the mechanical properties of That is, it is desirable that the heating for pre-sintering is performed in an atmosphere of an inert gas or a reducing gas, and a similar atmosphere is also desirable in heating and immediately before hot plastic working. The inventors of the present invention have found that it is effective to perform heating and sintering in a pressurized reducing gas or inert gas atmosphere as a method for shortening the required heating time in heating for temporary sintering. Is heading.

Next, the conditions for hot plastic working will be described in detail. In the transmission, since the spline of the sleeve meshes with the outer peripheral spline portion of the synchronizing ring via the chamfer during gear shifting, the outer peripheral tooth portion of the synchronizing ring is required to have mechanically excellent characteristics.
As described above, the copper-based sintered alloy used in the present invention has a true density ratio of 95% or more, a 0.2% tensile proof stress of 400 MPa or more, and a Rockwell B hardness of 70 or more. Even if it is used for, the outer peripheral tooth portion will not be worn or damaged. In order to obtain such a true density ratio of 95% or more, it is desirable to subject the sintered body to hot plastic working such as hot forging or hot extrusion.

When the hot forging method is used, a particle-dispersed copper alloy is used.
After molding the gold powder into a ring-shaped green compact,
600 ℃ or less in a reducing gas or inert gas atmosphere
5 minutes or more at the temperature above and below the melting start temperature of the copper alloy
95 by heating and hot forging in a closed mold
% On the outer peripheral surface of the ring at the same time as sintering to a true density ratio of
A spline meshing tooth portion is formed. Forging surface pressure at that time
As 6t / cm ² Hope to apply more pressure
Good.

When the hot extrusion method is used, the green compact is molded in a reducing gas or inert gas atmosphere at 600 as described above.
After heating for 5 minutes or more at a temperature not lower than ℃ and not more than the melting start temperature of the copper alloy, it is sintered by hot extrusion into a cylindrical body having a true density ratio of 95% or more. After the cylindrical body is cut into a ring shape, it is finished into a predetermined synchronizing ring shape by machining. In hot extrusion processing, it is desirable to give an extrusion ratio of 10 or more.

Incidentally, in order to reduce the machining cost, FIG.
As shown in steps (e) and (f) of step 1, the ring-shaped sintered body obtained by cutting the extruded material is reheated and hot-forged in the closed die, so that the outer circumference of the ring is reduced. It is also possible to shape the spline meshing teeth on the surface.

In heating and immediately before hot forging or hot extrusion, it is desirable to use a temperature of 600 ° C. or higher and lower than the melting start temperature of the copper alloy, as in the case of heating. This is because reheating to the melting start temperature of the copper alloy may cause a phase change in the copper alloy and induce deterioration of the properties of the sintered alloy. Also,
This is because if the temperature is lower than 600 ° C., it is difficult to increase the true density ratio of the sintered body to 95% or more because the deformation resistance of the copper-based sintered alloy is large.

[0065]

【Example】

[0066]

[Table 1]

[0067]

[Table 2]

Tables 1 and 2 show the compositions of the copper alloy powder samples containing the hard particles according to the examples of the present invention and the comparative examples, respectively, and the powders were molded and subjected to heating and hot plastic working ( In this case, the true density ratio of the sintered alloy obtained by hot forging) is shown. In these tables,
The numerical values relating to Zn, Ni, Sn, Si, Al, Pb, the solid lubricant, and Cu represent the weight% in the alloy powder matrix. On the other hand, the values relating to the hard particles represent% by weight with respect to the total alloy powder. The symbols A, B, C, D, and E representing the solid lubricant represent graphite, MoS ₂ , CaF ₂ , BN, and WS ₂ , respectively. Further, a symbol F representing an iron-based intermetallic compound,
G, H, I, and J are FeMo and FeC, respectively.
It represents r, FeW, FeTi, and FeB.

In the sample 34 marked with * 1 in the remarks column of Table 2, the particle-dispersed alloy powder was obtained by the mechanical mixing and pulverization treatment. The maximum particle size is set to 45 μm.

Sample 35 marked with * 2 in the remarks column
In, the particle-dispersed alloy powder was obtained by the mechanical mixing and pulverization treatment, but the average particle diameter of the hard particles was set to 30 μm by changing the treatment conditions.

In the sample 36 marked with an asterisk * 3 in the remarks column, the copper alloy powder and the hard particles were simply mixed without using the mechanical mixing and pulverizing treatment, and then the molding, heating,
And is sintered after hot plastic working.

Sample 37 marked with * 4 in the remarks column
In (1), the particle-dispersed alloy powder is obtained by the mechanical mixing and pulverization treatment, but the true density ratio of the sintered body is set to 93% by changing the hot plastic working conditions.

[0073]

[Table 3]

[0074]

[Table 4]

Tables 3 and 4 show the maximum particle size and average particle size of the hard particles, the mechanical properties, and the frictional sliding characteristics for the sintered body samples having the compositions and the true density ratios shown in Tables 1 and 2. Shows properties and resistance to sulfidation corrosion.

In Table 3, Samples 1 to 22 according to the examples of the present invention each have a value of 0.2 which is well over 400 MPa.
It can be seen that it has a% proof stress and exhibits an elongation of more than 5%. On the other hand, in Comparative Samples 23 to 37 in Table 4, most of the samples were 0.2 MPa below 400 MPa.
Many have only a% proof stress and also show an elongation of less than 2%. That is, it is understood that the sintered alloy samples according to the examples of the present invention have higher strength and higher toughness than the sintered alloy samples according to the comparative example.

Friction and sliding characteristics were measured using a ring-on-disc type friction tester as shown in FIG. In gear oil (Castrol-15W30), the sintered body test piece 1 is slid relative to the mating material 2 of the steel material SCM420 (carburized and quenched steel) via the sliding surface S. The test piece 1 has a ring shape having an outer diameter of 60 mm, an inner diameter of 45 mm, and a thickness of 5 mm, and is partially cut and shown in FIG. Mating material 3 has a diameter of 70 mm and 5 mm
Is a disk having a thickness of 1 and is rotated by the shaft 3 in the direction of the arrow. Specimen 1 is fixed, mating material 2
Is applied with a pressure W of 80 kgf / cm ² . The relative sliding speed between the test piece 1 and the mating material 2 on the sliding surface S was 6 m / sec, and the friction time was 1 hour. Table 3
As can be seen from Table 4, all of the sintered body samples 1 to 22 according to the examples of the present invention show a relatively high steady-state friction coefficient μ of 0.3 to 0.4. Thus, in the sintered body samples 23 to 37 of the comparative example, the value of the friction coefficient μ in the steady state varies. Especially about 0.7
The above μ value represents the μ value as a result of printing.

Regarding the amount of wear of the sintered body test piece 1 and the mating material 2, the samples of the examples show a stable and small amount of wear, while the samples of the comparative examples show extremely large amounts of wear. Some indicate the amount of wear and the amount of adhesion. In addition, in the wear amount in Table 4, the absolute value of the number with a minus sign represents the increase in weight due to adhesion, which means that seizure has occurred.

With respect to sulfidation corrosion resistance, 2 samples of the sintered body were placed in oil Castrol-15W30 held at 140 ° C.
After being immersed for 4 hours, the corrosion status of the samples was examined by optical microscopy. As can be seen from Tables 3 and 4, no abnormality was found in corrosion in the samples of the examples, but in the comparative sample 23, sulfide corrosion occurred.

Here, each of the sintered body samples 23 to 37 of the comparative example.
The specific drawbacks of the above are as follows.

In Sample 23, Z in the alloy base material was used.
Since the total content of n and Ni has not reached 5% by weight,
Sulfide corrosion occurred in the exposure test of the sintered body sample in oil.

In Sample 24, Z in the alloy base
Since the total content of n and Ni exceeds 40% by weight,
The toughness (elongation) of the sintered body is reduced.

In Sample 25, since the content of hard particles in the sintered body did not reach 10% by weight, the initial μ value was low, and seizure with the mating material finally occurred.

In sample 26, the sintered body was 50% by weight.
55% by weight of hard particles, the strength and toughness of the sintered body are reduced.

In Sample 27, the content of the hard particles in the sintered body was further increased to 60% by weight, so that the strength of the sintered body was further lowered.

In Sample 28, since the content of Sn in the sintered body was more than 20% by weight, the body was significantly hardened and attacked the mating material, causing seizure.

In Sample 29, since the Si content in the sintered body was more than 5% by weight, the strength and toughness of the sintered body were deteriorated.

In the sample 30, Al in the sintered body was used.
Content of more than 5% by weight impairs sinterability and reduces the strength and toughness of the sintered body.

In the sample 31, the content of Pb in the sintered body exceeds 3% by weight, so that Pb is contained inside the sintered body.
Segregates, and as a result, the strength of the sintered body decreases.

In Sample 32, since the content of the graphite solid lubricant in the sintered body exceeded 5% by weight, the strength and toughness of the sintered body were deteriorated.

In sample 33, Mo in the sintered body
Since the content of the solid lubricant of S ₂ exceeds 5% by weight, the sintered body is fractured before showing the elongation of 0.2%.

In Sample 34, the maximum particle size of the hard particles exceeds 30 μm, so the strength and toughness of the sintered body are reduced.

In sample 35, since the average particle diameter of the hard particles exceeds 15 μm, the strength and toughness of the sintered body are deteriorated.

In Sample 36, the alloy powder having a predetermined composition and the hard particles were simply mixed and then sintered without mechanical pulverization and mixing treatment, so that the strength and toughness of the sintered material were deteriorated. Further, since the reaction layer between the hard particles and the base is not formed and coarse hard particles are present, the hard particles fall off from the base during sliding and seizure occurs with the mating material.

In Sample 37, the workability in hot plastic working was insufficient and the true density ratio of the sintered body was 93%, so that the strength and toughness of the sintered body were reduced. .

[0096]

[Table 5]

Table 5 shows the friction and sliding characteristics of the synchronizing ring produced by using the sintered alloys shown in Tables 1 and 2, whether or not ring cracks were generated, whether or not the ring inner surface was seized, and the taper cone. The friction coefficient at the initial stage (up to 300 times) and the stable period on the friction surface is shown. In order to evaluate these friction-sliding characteristics, a synchronizing ring as shown in FIG. 4 was prepared, and the synchronizing ring was tested by a synchro ring unit tester. The test conditions at this time are as follows.

Material of taper cone: SCM420 (carburized and hardened steel) Rotation speed of taper cone: 3000 rpm Pressing load: 50 kgf Oil used: Castrol-15W30 (oil temperature 80 ° C) Operation of taper cone: 0.8 second pressing per cycle Number of separation cycles for 1.5 seconds: 10,000 cycles As can be seen from Table 5, Samples 1 to 1 according to the examples of the present invention
The synchronizing ring formed of the sintered alloy of No. 22 does not cause ring cracking or seizure, has a relatively large initial friction coefficient μ of 0.2 to 0.3, and even in the stable period, The μ value within the preferable range is maintained.

On the other hand, in the synchronizing rings formed of the sintered alloys of the comparative samples 23 to 37, as shown in Table 3, the 0.2% proof stress of the samples other than the sample 25 is 400 MPa which is the target value. Since all the samples were satisfied, cracks occurred in all the samples except the sample 25, and in some cases, the composition of the sintered body was improper, and during the test, seizure with the taper cone part of the mating steel material occurred on the inner peripheral surface of the ring. In many cases, seizure occurred from an early stage and all comparative samples except Sample 25 cracked during the plateau. Therefore, when seizure occurs on the friction surface of the ring, the friction coefficient shows an abnormal value, and when cracks occur on the ring, the testing machine stops and the friction coefficient cannot be measured. Could not be determined. Sample 25 has high strength and therefore did not crack, but seized because it did not contain hard particles. As described above, it was found that the synchronization rings of Comparative Samples 23 to 37 could not stand practical use.

[0100]

[Table 6]

Table 6 shows the influence of the average particle size and flow characteristics of the particle-dispersed copper alloy powder on the powder formability.
In Table 6, Cu-18 wt% Zn-18 wt% N
800 g of mixed powder was prepared in which 20 wt% of FeMo particles having an average particle diameter of 50 μm was mixed with the atomized alloy powder of i. This alloy powder was mechanically alloyed by a vibrating ball mill. During the mechanical alloying process, processing time,
By changing the amount of ball thrown and the vibration conditions,
Powder samples 41-54 having various average particle sizes as shown in Table 6 were prepared. The flowability of these powder samples was evaluated by the time required for 50 g of powder to completely flow through an orifice tube having a diameter of 2.5 mm. Each powder sample has an outer diameter of 140 mm and 80
It was formed into a ring shape having an inner diameter of mm and a thickness of 3 mm and was sintered. The powder was powdered into the mold using an automatic powder feeder, but for powders with extremely poor fluidity, the mold was manually filled. Table 6 shows the appearance of the molded body thus obtained and the appearance of the sintered body.

As is clear from Table 6, all of the powder samples 41 to 50 having the average particle diameter belonging to the present invention are 50.
A fluidity of 30 seconds or less per g was obtained, a good powder compact having no cracks or chips was obtained, and a good sintered body having no warp was obtained.

On the other hand, in the comparative powder samples 51 to 54, the following problems occurred.

In sample 51, since the average particle size was extremely small and was 25 μm, powder was clogged in the orifice tube during the fluidity evaluation test, and the fluidity could not be determined. In addition, since the powder has poor fluidity, the powder compact has an uneven density, a corner portion is chipped, and the sintered body is warped.

In sample 52, the particle size was 40 μm and still less than 50 μm, so the fluidity of the powder was poor and the sulfidation time per 50 g was 48 seconds, so that it could be used in a mass production molding process. Have difficulty. Further, since a difference in density occurs between the corner and the center of the molded body, the corner of the molded body was chipped and the sintered body was warped.

In the sample 53, since the particle size is 280 μm, which is larger than 250 μm, it is difficult to uniformly compress the powder in the mold, and as a result, a non-uniform state of density occurs in the molded body, The corners of the body were chipped and the sintered body was warped.

In Sample 54, since the particle size was 350 μm, which was larger, it was difficult to uniformly compress the powder in the mold, which resulted in uneven density in the molded body, and The corners of the body were chipped and the sintered body was warped.

[0108]

[Table 7]

[0109]

[Table 8]

Tables 7 and 8 show the mechanical properties and true density ratio of the sintered bodies obtained by the various steps (a) to (f) shown in FIG. In Table 7 and Table 8, C
Composition of u-18 wt% Zn-18 wt% Ni and 1095
An atomized alloy powder having a melting start temperature of ° C was prepared. 25% by weight of F based on this atomized alloy powder
800 g of the mixed powder containing the eMo particles was mechanically alloyed by a vibrating ball mill.

The grain-dispersed copper alloy powder subjected to mechanical alloying was subjected to molding, heating, and hot plastic working in any of the steps (a) to (f) to obtain a sintered alloy. Note that in Samples 61 to 66 and 72 to 76, all heating steps were performed in nitrogen gas.
Further, in Samples 67 to 71 and 77 to 83, all heating steps were performed in hydrogen gas. However, the heating process for samples 84 and 85 was performed in air.

As can be seen from Table 7, all the samples 61 to 71 according to the examples of the present invention have a true density ratio of 95% or more, a 0.2% proof stress of more than 500 MPa and a Rockwell B hardness of more than 90. It can be seen that it has an HRB and has excellent mechanical properties for a synchronizing ring.
It was confirmed that such sintered body samples 61 to 71 can be formed with the outer peripheral tooth portion of the synchronizing ring by hot forging.

On the other hand, the comparative samples 72 to 85 had the following defects depending on the manufacturing process conditions.

In sample 72, since the true density ratio of the powder compact was 70% or less, ie 55%, a part of the compact was chipped during the conveying process of the compact.

In the sample 73, the heating temperature in the heating step was 450 ° C., which was lower than 600 ° C., so that the powder particles could not be firmly bonded to each other, and 400 M
The yield strength exceeding Pa was not obtained. Further, since the heating temperature is low and the deformation resistance of the green compact is large, the tooth portion on the outer peripheral surface of the ring could not be formed by forging.

In sample 74, the forging surface pressure was low and
Since it was t / cm ² , the powder particles could not be firmly bonded to each other, and the yield strength exceeding 400 MPa was not obtained. Further, the forging surface pressure was insufficient, and the tooth portion on the outer peripheral surface of the ring could not be formed by forging.

In sample 75, the extrusion ratio was 6 which was low, so that the powder particles could not be firmly bonded to each other, and 400 M
The yield strength exceeding Pa was not obtained.

In the sample 76, the heating temperature in the heating step was 500 ° C., which was lower than 600 ° C., so that the deformation resistance of the green compact increased and the green compact was clogged during hot extrusion.

In the sample 77, the heating time in the heating step was 3 minutes, which was less than 5 minutes, so that the powder particles could not be firmly bonded to each other, and the yield strength exceeding 400 MPa was not obtained. In addition, since the deformation resistance of the green compact is large, it is impossible to form the tooth portion on the outer peripheral surface of the ring by forging.

In Sample 78, the heating temperature in the heating step exceeds the melting start temperature of the alloy powder base 115.
Since it was 0 ° C, the mechanical properties of the sintered body deteriorated and the proof stress exceeds 400 MPa, but the hardness HR exceeds 70
B was not obtained.

In Sample 79, the heating time in the heating step was 2 minutes, which was less than 5 minutes. Therefore, the deformation resistance of the pre-sintered body was increased, and the tooth portion was formed on the outer peripheral surface of the ring by forging. I couldn't.

In the sample 80, the heating temperature in the heating step was 1150 ° C., which was higher than the melting start temperature of the alloy, so the mechanical properties of the alloy deteriorated and the yield strength was 400.
Hardness HRB exceeding MPa but exceeding 70 could not be obtained.

In the sample 81, the heating temperature in the heating step was 500 ° C., which is lower than 600 ° C., so that the deformation resistance of the extruded material was increased and the tooth portion could be formed on the outer peripheral surface of the ring by forging. There wasn't.

In the sample 82, the heating time in the heating step was 3 minutes, which was less than 5 minutes, so that the deformation resistance of the extruded material was increased and the tooth portion could be formed on the outer peripheral surface of the ring by forging. There wasn't.

In sample 83, the forging surface pressure was low and 3
Since it was t / cm ² , it was not possible to form the tooth portion on the outer peripheral surface of the ring by forging.

In the sample 84, since the green compact was heated in the air, the surface of the green compact was oxidized and the binding of the powder particles was inhibited. As a result, the yield strength exceeding 400 MPa was not obtained.

Also in the sample 85, since the powder compact was heated in the atmosphere, the powder surface was oxidized and the binding of the powder particles was inhibited, so that the yield strength exceeding 400 MPa was not obtained.

[0128]

As described above, according to the present invention, a relatively high stable friction coefficient exceeding 0.2 can be maintained at the time of synchronization without causing sulfidation corrosion in the lubricating oil containing sulfur. A copper-based sintered alloy synchronizing ring for a transmission having excellent mechanical properties can be provided with excellent economical efficiency.

[Brief description of drawings]

FIG. 1A is a schematic structural diagram of a sintered body using a mechanical mixing and pulverizing process according to the present invention, and FIG. 1B is a schematic structure of a sintered body using a conventional simple powder mixing process. It is a typical organizational chart.

FIG. 2 is a process drawing showing various manufacturing methods for obtaining a sintered alloy synchronization ring for a transmission according to the present invention.

FIG. 3 is a diagram for explaining a friction sliding characteristic test of a sintered material.

FIG. 4 is a perspective view showing an example of a transmission synchronization ring.

[Explanation of symbols]

 1 Sintered body sample 2 Counterpart material 3 Axis S Sliding surface W Pressure load

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[Procedure amendment]

[Submission date] December 21, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0077

[Correction method] Change

[Correction content]

Friction and sliding characteristics were measured using a ring-on-disc type friction tester as shown in FIG. In gear oil (Castrol-15W30), the sintered body test piece 1 was steel SCM420 (carburized and hardened steel).
Of the mating member 2 through the sliding surface S. The test piece 1 has a ring shape having an outer diameter of 60 mm, an inner diameter of 45 mm, and a thickness of 5 mm, and is partially cut and shown in FIG. Mating material 2 is 70 mm
Is a disc having a diameter of 5 mm and a thickness of 5 mm and is rotated by the shaft 3 in the direction of the arrow. The test piece 1 is fixed, and a pressure W of 80 kgf / cm ² is applied to the mating material 2. Test piece 1 and mating material 2 on sliding surface S
Had a relative sliding speed of 6 m / sec and a friction time of 1 hour. As can be seen from Tables 3 and 4, all of the sintered body samples 1 to 22 according to the examples of the present invention exhibit a relatively high steady-state friction coefficient μ of 0.3 to 0.4. On the other hand, in the sintered body samples 23 to 37 of the comparative example, the value of the friction coefficient μ in the steady state varies.
In particular, a μ value of about 0.7 or more represents a μ value as a result of printing.

Claims (24)

[Claims] 1. A transmission synchronizing ring including a copper-based sintered alloy, wherein the sintered alloy has a structure in which hard particles are uniformly dispersed in old powder particles including a base of the copper alloy, and 400 MPa A synchronizing ring for a transmission, which has the above 0.2% tensile strength and a Rockwell B hardness of 70 or more. 2. The friction surface has a friction coefficient of 0.2 or more when the taper cone friction surface of the inner peripheral portion of the synchronizing ring is synchronized with the taper cone portion of the mating steel material in the lubricating oil. The synchronization ring for a transmission according to claim 1. 3. The synchronizing ring for a transmission according to claim 1, wherein the hard particles have a maximum particle diameter of 30 μm or less and an average particle diameter of 15 μm or less. 4. The sintered alloy, as the hard particles,
Iron-based intermetallic compound particles and M within the range of 10 to 50% by weight
4. The synchronizing ring for a transmission according to claim 1, further comprising at least one of O particles. 5. The iron-based intermetallic compound particles are FeM.
5. The transmission synchronizing ring according to claim 4, comprising at least one selected from o, FeCr, FeTi, FeW, and FeB. 6. The copper alloy base material contains at least one of Zn and Ni within a range of 5 to 40% by weight and the balance of copper, and has an excellent resistance to sulfidation corrosion. A synchronizing ring for a transmission according to any one of items 1 to 5. 7. The copper alloy base is 3 to 20 wt% Sn.
The synchronization ring for a transmission according to claim 6, further comprising: 8. The copper alloy base is 1-5 wt% S.
i, 1-5 wt% Al, and 0.5-3 wt% P
8. The transmission synchronization ring according to claim 6, further comprising at least one of b. 9. The copper alloy base is graphite, MoS ₂ , CaFe ₂ , WS ₂ and BN within a range of 5% by weight or less.
9. The transmission synchronizing ring according to claim 6, further comprising at least one of the solid lubricants. 10. A particle-dispersed copper alloy powder in which hard particles are uniformly dispersed in a copper alloy matrix, a powder compact of the particle-dispersed copper alloy powder is formed, and the powder compact is heated. A method for manufacturing a synchronizing ring for a transmission, comprising the step of solidifying the powder compact to a true density ratio of 95% or more by hot plastic working. 11. The particle-dispersed copper alloy powder contains, as the hard particles, at least one of iron-based intermetallic compound particles and Mo particles within a range of 10 to 50% by weight. A method of manufacturing a synchronizing ring for a transmission according to item 1. 12. The iron-based intermetallic compound particles are FeM.
The method for manufacturing a transmission synchronization ring according to claim 11, further comprising at least one selected from o, FeCr, FeTi, FeW, and FeB. 13. In the preparation of the particle-dispersed copper alloy powder, a mixed powder containing copper alloy powder and hard particles is prepared, and the mixed powder is subjected to mechanical alloying method (mechanical alloying method) and mechanical mixing method. The hard particles are pulverized to have a maximum particle size of 30 μm or less and an average particle size of 15 μm or less by performing a mixing and pulverizing process of at least one of (mechanical grinding method) and a granulating method. 13. The method of manufacturing a synchronizing ring for a transmission according to claim 10, wherein the powder is dispersed in a copper alloy powder body. 14. The copper alloy matrix according to claim 10, wherein the copper alloy matrix contains at least one of Zn and Ni within the range of 5 to 40% by weight and the balance copper. Of manufacturing a synchronized ring for a transmission. 15. The copper alloy substrate is 3 to 20% by weight of S.
The method for manufacturing a transmission synchronizing ring according to claim 14, further comprising n. 16. The copper alloy base is 1 to 5% by weight of S.
i, 1-5 wt% Al, and 0.5-3 wt% P
The method for manufacturing a transmission synchronizing ring according to claim 14 or 15, further comprising at least one of b. 17. The copper alloy base has a range of 5% by weight or less.
Graphite and MoS in the enclosure ₂ , CaFe₂ , WS₂ , And B
Further comprising at least one solid lubricant of N
And any one of claims 14 to 16 characterized in that
A method of manufacturing a described synchronization ring for a transmission. 18. The particle-dispersed copper alloy powder is 50-2.
The method of manufacturing a transmission synchronizing ring according to any one of claims 10 to 17, wherein the method has a mean particle size in the range of 50 µm. 19. The particle-dispersed copper alloy powder is 2.5
The method for producing a synchronizing ring for a transmission according to any one of claims 10 to 18, wherein the orifice tube having a diameter of mm has a fluidity of flowing down per 50 g in 30 seconds or less. 20. The powder compact of the particle-dispersed copper alloy powder has a true density ratio of 70% or more, and is 6 in an atmosphere containing at least one of an inert gas and a reducing gas.
Immediately after being heated at a temperature not lower than 00 ° C. and not higher than the melting start temperature of the copper alloy base for 5 minutes or more, it is solidified into a ring-shaped body having a true density ratio of 95% or more by hot forging in a closed mold. The method for manufacturing a transmission synchronizing ring according to any one of claims 10 to 19, wherein a spline meshing tooth portion is formed on the outer peripheral surface of the ring-shaped body together. 21. The powder compact of the particle-dispersed copper alloy powder has a true density ratio of 70% or more, and is 6 in an atmosphere containing at least one of an inert gas and a reducing gas.
It is made into a pre-sintered body by heating it at a temperature in the range of not lower than the melting start temperature of the copper alloy base at 00 ° C. or higher for 5 minutes or longer. A true density ratio of 95% or more was obtained by hot forging in a closed mold immediately after being heated at a temperature within a range of 600 ° C. or higher in the atmosphere containing the above and below the melting start temperature of the copper alloy base for 5 minutes or more. 20. The transmission synchronizing ring according to claim 10, wherein the spline meshing tooth portion is formed on the outer peripheral surface of the ring-shaped body while being solidified into the ring-shaped body. Manufacturing method. 22. The powder compact of the particle-dispersed copper alloy powder has a true density ratio of 70% or more, and is 6 in an atmosphere containing at least one of an inert gas and a reducing gas.
A copper-based sintered alloy having a true density ratio of 95% or more is obtained by immediately performing hot extrusion after heating at a temperature of 00 ° C. or higher and a temperature of the melting start temperature of the copper alloy base or lower for 5 minutes. The method for manufacturing a transmission synchronizing ring according to any one of claims 10 to 19. 23. The powder compact of the particle-dispersed copper alloy powder has a true density ratio of 70% or more, and is 6 in an atmosphere containing at least one of an inert gas and a reducing gas.
It is made into a temporary sintered body by heating for 5 minutes at a temperature not lower than 00 ° C. and not higher than the melting start temperature of the copper alloy base, and then the temporary sintered body again contains at least one of an inert gas and a reducing gas. A copper-based sintered alloy having a true density ratio of 95% or more is immediately subjected to hot extrusion after being heated to a temperature of 600 ° C. or higher in an atmosphere containing the same and a temperature not higher than the melting start temperature of the copper alloy base. The method for manufacturing a transmission synchronizing ring according to any one of claims 10 to 19. 24. The copper-based sintered alloy obtained by the hot extrusion is again 600 ° C. or higher in an atmosphere containing at least one of an inert gas and a reducing gas, and the melting start temperature of the copper alloy base. Immediately after being heated at the following temperature for 5 minutes or more, a ring-shaped body having a true density ratio of 95% or more is immediately formed by hot forging in a closed mold, and at the same time, spline meshing teeth are formed on the outer peripheral surface of the ring-shaped body. The method for manufacturing a transmission synchronization ring according to claim 22 or 23, wherein the portion is molded.