JPH0699730B2 - Sintered vibration-proof alloy manufacturing method and sintered part manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a sintered vibration-isolating alloy and a method for producing a sintered part containing at least a part of the sintered anti-vibration alloy. The sintered anti-vibration alloy of the present invention can be used as a metal material suitable for a mechanical component for suppressing noise generation and vibration generation of vehicles, mechanical devices, etc., like general vibration-proof alloys. Further, the sintered component of the present invention can also be applied to a mechanical component such as a vehicle or a mechanical device that suppresses noise and vibration.

[Prior Art] Flake graphite cast iron obtained by molding and sintering cast iron powder or a mixture of cast iron powder, blunt iron powder, and graphite powder has been conventionally known as a sintered anti-vibration alloy (Japanese Patent Publication No. 60-23184, Japanese Patent Publication No. 55-36259). Further, a sintered anti-vibration alloy composed of an iron or iron alloy-based sintered body and a metal such as Mg, Pb, or Sn impregnated in the pores of the sintered body is known (Japanese Patent Publication No.
59-34761), and a sintered anti-vibration alloy composed of an iron or iron alloy-based sintered body and a resin impregnated into the pores of the sintered body is also known (JP-A-59-347). 145764 publication).

[Problems to be Solved by the Invention] Generally, the damping ability of a metal material tends to decrease as the strength increases. However, in applications where vibration or noise is a problem, materials with high strength are often used,
Therefore, the vibration-proof alloy is required to have high strength and high damping capacity.

The above-mentioned conventional sintered vibration-damping alloy has a composite type vibration-damping mechanism (using viscous flow or plastic flow at the interface between the mother phase and the second phase), and Materials and graphite, Mg, Pb, S
n, the vibration damping effect is obtained by the difference in the vibration transmission characteristics with the second material such as synthetic resin. That is, the vibration damping characteristic of the material itself is used.

However, conventional sintered vibration-damping alloys that utilize the vibration damping characteristics of such materials themselves have vibration damping effects but are not sufficient, and there is a limit in terms of strength to increase damping capacity. Further, in flake graphite cast iron in which iron-based powder and graphite powder are mixed in advance, it is necessary to add excessive graphite powder in order to improve the vibration damping effect. Therefore, there is a drawback that the sintering of the iron-based powder becomes insufficient due to the influence of the excessively added graphite powder and the strength becomes low (tensile strength is about 10 kgf / mm ² ).

Further, as described above, since strength and damping capacity are generally contradictory properties, there is a limit in strength when applying the sintered vibration-proof alloy to parts requiring high strength such as automobile parts, The range of use is limited. For example, when a sintered anti-vibration alloy is applied to a gear that is susceptible to vibration and noise, the sintered anti-vibration alloy should have the required strength (tooth root bending stress, tooth surface contact stress, etc.) for the gear tooth itself. Since it is difficult to hold it, it is often not possible to apply the sintered anti-vibration alloy to the entire parts including the teeth, and it is necessary to further increase the strength of at least the portion requiring strength.

The present invention improves vibration damping effect in a sintered vibration damping alloy by converting vibration energy into relative kinetic energy between a sintered body as a base material and a second material without lowering strength. Another object of the present invention is to provide a sintered component that includes a part of a sintered anti-vibration alloy having an improved anti-vibration effect and can be applied to a site requiring strength.

[Means for Solving the Problems] The method for producing a sintered anti-vibration alloy according to claim 1, wherein a sintered body formed by sintering a metal powder and having pores is filled with water or an organic substance. Characterized in that it comprises a step of permeating a solvent in which a fine powder is mixed with a solvent, and a step of allowing the fine powder to remain in the pores by evaporating the water or the organic solvent in a heated or reduced pressure state. To do.

The above-mentioned sintered body is manufactured by a general powder metallurgy technique of a powder compression sintering method in which metal powder is used as a main raw material and is molded and sintered. This metal powder is not particularly limited, and examples thereof include blunt iron-based, iron-copper-based, iron-carbon-based, iron-carbon-copper-based, iron-nickel-based iron-based alloy powders, copper-based alloy powders, and aluminum. Various metal powders such as a system alloy powder can be used. In addition, iron having a so-called ferromagnetic type (which uses magnetic and mechanical static history associated with magnetic domain type irreversible movement)-
It is also possible to use a chromium-based alloy powder or the like. Further, it is also possible to add a powder having its own damping ability such as graphite powder.

In the present invention, the particle size of the metal powder used as the raw material, the porosity of the pores, and the porosity of the pores It is preferable to specify the average pore diameter of the pores as follows.

That is, in the present invention, when considering only the anti-vibration effect, it is preferable that the larger the contact area between the inner wall surface of the pores of the sintered body and the fine powder held on the inner wall of the pores, the higher the vibration isolation effect. Therefore, as long as the strength of the sintered body and the particle size of the fine powder allow it, the larger the porosity and the smaller the average pore diameter, the contact area between the inner wall surface of the pores and the fine powder. Is preferred, which is preferable. Specifically, the porosity of the holes is 10
-40%, and the average pore diameter is 20-150 μm.
Particularly, it is preferable that the porosity is 15 to 25% and the average pore diameter is 40 to 80 μm. If the porosity of the pores is less than 10%, the absolute amount of fine powder that can be retained in the pores will be small, and the desired vibration isolation cannot be obtained. Further, if the porosity is more than 40%, the strength of the sintered body decreases, which is not preferable. Further, if the average pore diameter of the pores is smaller than 20 μm, it becomes difficult to hold the fine powder on the inner wall surface of the pores, and if it is larger than 150 μm, the strength of the sintered body decreases, which is not preferable.

The porosity and the average pore diameter of the pores can be specified mainly by changing the average particle diameter of the metal powder as a raw material and the molding density at the time of molding the metal powder. Therefore, in order to specify the porosity and the average pore diameter of the pores in the preferable range described above, the size of the average particle diameter of the metal powder as the raw material is 60 to 350 mesh, and the metal powder is molded. In this case, the molding density of iron-based powder may be 5.8 to 6.8 g / cm ³ . Furthermore, the sintering conditions include a sintering temperature of 1120.
It is preferable to carry out at ˜1250 ° C., sintering time of 30 to 120 minutes, and in vacuum or nitrogen atmosphere.

The fine powder is held in the pores of the sintered body. The fine powder is not particularly limited as long as it has a particle diameter much smaller than the pore diameter of the pores of the sintered body and can be held on the inner wall surface of the pores of the sintered body. A material that is soft and has a high damping capacity is preferable. For example, it may be graphite fine powder, metal fine powder such as Pb or Mg, or ceramic fine powder. The larger the amount of this fine powder held in the pores of the sintered body, the higher the vibration damping effect, which is preferable. Due to the relationship between the porosity of pores and the average pore diameter, it is preferable to hold the fine powder so as to occupy a volume of 10 to 95% of the pore volume of the sintered body. The average particle size of the fine powder is 0.01-10 μm.
Can be set, and particularly preferably 0.1 to 2 μm.

When holding this fine powder in the pores of the sintered body,
Since it is preferable to keep the fine powder in the pores as uniformly as possible, for example, when graphite powder is used as the fine powder, the mixed solvent obtained by mixing the graphite powder with water or an organic solvent is used as the pores of the sintered body. Then, the graphite powder alone may be left in the pores by evaporating the water or the organic solvent by heating or reducing the pressure.

The method for producing a sintered vibration-proof alloy according to claim 2 is the method according to claim 1, wherein after the fine powder remains in the pores of the sintered body, the fine powder remains in the pores. At least a part of the obtained sintered body is compressed or rolled.

According to the manufacturing method of claim 2, in the same manner as in the manufacturing method of claim 1, after the fine powder remains in the pores of the sintered body, the sintering in which the fine powder remains in the pores At least a part of the body is compressed or rolled. This compression process is 4-12
It is preferable that the pressure is ton / cm ^{2 and} the rolling process is performed at a compression rate of 15 to 50%, and the density after compression or rolling is 6.9 to 7.7 g / cm ³ .

The method for producing a sintered component according to claim 3, wherein a sintered body is formed by sintering a metal powder and has pores, and a fine powder held in the pores of the sintered body. A firing consisting of a vibration-proof part made of a vibration-damping alloy and a strength part made of a high-density metal sintered body having a higher density than a sintered body formed integrally with the vibration-proof part and constituting the vibration-proof part. A method for manufacturing a bonded component, wherein water or organic matter is introduced into the pores of the low density portion of a sintered body consisting of a high density portion partially increased in density and a low density portion other than the high density portion. After permeating the mixed solvent in which fine powder is mixed with the solvent,
It is characterized in that the fine powder is allowed to remain in the pores of the low density portion by heating or depressurizing to evaporate the water or the organic solvent to form the vibration isolating portion.

The vibration isolator and the strength portion are integrally formed.
The anti-vibration part has a density of 6.9 to 7.7 g / cm ³ , the strength part and the density are 7.0 to 7.
It is preferably 8 g / cm ³ . This anti-vibration part and strength part are
It can also be formed by the manufacturing method according to claim 2. That is, the sintered vibration-damping alloy obtained by the manufacturing method according to claim 2 is partly recompressed to have a higher density than other parts, and the other part is a vibration-proof part. Can be formed. But,
It is preferable that the strength portion is further re-sintered after re-compression and the pressure-bonded surface of the sintered body formed by the re-compression is metal-bonded. This is because the strength is further increased. Further, it is preferable that the strength portion does not hold the fine powder, and it is preferable that after forming the strength portion formed of the high-density metal sintered body, the vibration-proof portion other than the strength portion holds the fine powder. . This is because the strength increases when the metal sintered bodies are in direct contact with each other. Therefore, in order to form the vibration isolation portion and the strength portion that does not hold fine powder,
In the manufacturing method described, the fine powder is held in the pores of the low density portion of the sintered body, which is composed of the high density portion where the density is partially increased and the low density portion other than the high density portion. In order to obtain a sintered body composed of the high density part in which the density is partially increased and the low density part other than the high density part, only the part corresponding to the high density part when powder-molding the metal powder is used. It can be obtained by increasing the compression ratio, molding the powder, and sintering the powder.
It can also be obtained by powder-molding the whole part at a uniform compression ratio and sintering, and then re-compressing only the part corresponding to the high-density part and re-sintering. Furthermore, when powder-molding the metal powder, the compression ratio of only the portion corresponding to the high-density portion is increased to powder-form, and after sintering this, only the portion corresponding to the high-density portion is recompressed and re-compressed. It can also be obtained by sintering.

The method for manufacturing a sintered part according to claim 4 is the method according to claim 3, wherein after the fine powder is left in the pores of the sintered body, the fine powder is left in the pores. It is characterized in that at least a part of the sintered body is compressed or rolled.

[Operation of the Invention] According to the method for producing a sintered anti-vibration alloy according to claim 1, a sintered anti-vibration method in which fine powder is held in the pores of a sintered body formed by sintering a metal powder. The alloy can be easily obtained. When vibration energy is applied to this sintered anti-vibration alloy, the fine powder existing in the pores of the sintered body moves due to the vibration energy. That is, the vibration energy applied to the (this) sintered anti-vibration alloy is transmitted from the inner wall surface of the pores to the fine powder through the contact surface between the inner wall surface of the sintered body and the fine powder, and the kinetic energy of the fine powder is transferred. Is converted to and absorbed by the sintered vibration-proof alloy.

According to the method for producing a sintered vibration-proof alloy according to claim 2, the pores of the sintered body are crushed, and the fine powder is held in the crushed pores and the inner wall surface of the crushed pores is held. It is possible to obtain a sintered anti-vibration alloy that is partially sandwiched and consolidated. Therefore, the compacted sintered anti-vibration alloy has a larger contact area between the inner wall surface of the pores and the fine powder as compared with the non-consolidated sintered anti-vibration alloy. The ratio of the vibration energy converted into the kinetic energy of the fine powder increases. In addition, since it is consolidated and the density is increased, the strength is also increased.

A sintered part obtained by the method for manufacturing a sintered part according to claim 3 or 4, is composed of a vibration-proof part made of the above-mentioned sintered vibration-proof alloy having a vibration-proof effect, and a high-density metal sintered body. The vibration-proof part has the vibration-proofing effect of the sintered vibration-proof alloy obtained by the manufacturing method according to claim 1 and the strength is strong. The part has the strength of the densified portion. Further, since the metal sintered bodies are in direct contact with each other in the strength portion which does not hold the fine powder, the strength is further increased.

Moreover, in the manufacturing method according to any one of claims 1 to 4, by adjusting the addition amount of the fine powder when the fine powder is mixed with water or an organic solvent, fine particles that are easily retained in the pores of the sintered body can be obtained. The amount of powder, and thus the contact area between the fine powder and the inner wall surface of the pore, can be adjusted.

[Examples] Examples of the present invention will be described below.

(Example 1) FIG. 1 is a diagram schematically showing a partially enlarged cross-sectional view of a sintered anti-vibration alloy of Example 1.

The sintered anti-vibration alloy of Example 1 is composed of a sintered body 1 and graphite fine powder 3 held in pores 2 of the sintered body 1.
The sintered anti-vibration alloy of Example 1 was manufactured as follows.

Based on 100% by weight, 0.8% by weight of graphite powder of natural graphite, 0.8% by weight of zinc stearate, and the rest of the raw material powder consisting of atomized iron powder having a grain size of 100 to 350 mesh were mixed with a V-type mixer 20 Mixed for minutes. And
After compression molding with a normal mold at a pressure of 2.4 ton / cm ² to a molding density of 6.0 g / cm ³ , sintering in a mesh belt type continuous sintering furnace at 1130 ° C for 40 minutes in an N ₂ atmosphere Sintering was performed under the conditions. As a result, a sintered body having a porosity of about 23% and an average pore diameter of 40 μm was obtained. Then, the sintered body was immersed in a mixed solvent consisting of 25% by weight of graphite fine powder having an average particle size of 1 μm and the balance of 75% by weight of water in the atmosphere for 2 hours to form pores in the sintered body. The graphite mixed solution was permeated into the inside. Then, using an electric furnace, the mixture was heated at 80 ° C. for 2 hours to evaporate the water and leave only the graphite fine powder in the pores of the sintered body to obtain the sintered anti-vibration alloy of Example 1. . As a result, 1.1 g of graphite remained in the pores per 100 g of the sintered body.

(Example 2) 0.8% by weight of Accra wax and the balance being Fe-10Cr- having a ferromagnetic damping mechanism when the whole is 100% by weight.
Using a raw material powder consisting of 3Mo alloy powder (average particle size 80μm), compression molding at a pressure of 6ton / cm ² yields a molding density of 6.6g / c.
and m ^3, and 1250 ° C. In badge type sintering furnace, 60 minutes, the sintering antivibration alloy to the second embodiment similar except that perform sintering as in Example 1 by sintering conditions of a vacuum atmosphere Manufactured. In this sintered vibration-damping alloy, 0.7 g of graphite remained in the pores with respect to 100 g of the sintered body.

The sintering vibration-control metal alloy obtained in Example 3 above Example 1, further 8.0ton / cm ²
The re-compression density was set to 7.5 g / cm ³ by re-compression processing under the pressure of 1 to obtain a sintered anti-vibration alloy of Example 3. FIG. 2 schematically shows a partially enlarged sectional view of the sintered anti-vibration alloy of Example 3. As can be seen from FIG. 2, the voids 2'in the sintered vibration-damping alloy of Example 3 are crushed, and the graphite fine powder 3 is sandwiched between the inner walls of the crushed voids 2 '. There is. The sintered anti-vibration alloy of Example 3 had a porosity of about 4% and an average pore diameter of 20 μm.

(Example 4) A raw material powder consisting of 0.8% by weight of zinc stearate and the balance of atomized iron powder having a grain size of 100 to 350 mesh was used at a pressure of 10 ton / cm ² when the whole amount was 100% by weight. A sintered anti-vibration alloy of Example 4 was obtained in the same manner as in Example 3 except that the compression process was performed to obtain a recompression density of 7.8 g / cm ³ . The amount of graphite existing in the pores was 1.1 g per 100 g of the sintered body.

(Evaluation 1) Table 1 shows the results of measuring the damping capacity of the sintered vibration-damping alloys of Examples 1 to 4 above. In addition, the strength of the sintered anti-vibration alloy of Examples 1 and 2 was measured. The results obtained are also shown in Table 1. The damping ability was measured by a free vibration damping method by impulse excitation, and the strength was measured by a tensile test. Further, as a comparative example, the damping ability and strength of a commercially available flake graphite cast iron (trade name: FC23) were similarly measured, and the results are also shown in Table 1.

As is clear from Table 1, all of the sintered anti-vibration alloys of Examples 1 to 4 showed a logarithmic damping ratio of 2.9 × 10 ^-2 or more, and the damping ability of the flaky graphite cast iron of the comparative example was about 3%. It can be seen that it has more than double the damping ability. In the sintered anti-vibration alloys of Examples 1 to 4, graphite fine powder having damping ability is held in the pores of the sintered body. Therefore, the vibration energy applied to the sintered anti-vibration alloy is converted into the kinetic energy of the graphite fine powder to obtain a vibration damping effect, and at the same time, the composite type due to the difference in the vibration transfer characteristics between the sintered body and the graphite fine powder is obtained. The damping function of is also used to obtain the anti-vibration effect.

Further, the sintered vibration-damping alloy of Example 2 in which a sintered body was formed by using Fe-Cr-Mo based alloy powder showed a logarithmic damping factor of 4.6 x 10 ^-2 , and the damping ability of flake graphite cast iron. 4 times or more of the damping capacity. This is because the sintered anti-vibration alloy of Example 2 has Fe-Cr- which has a ferromagnetic damping function in the raw material powder of the sintered body.
It is considered that since the Mo-based alloy powder is used, in addition to the effect of the first embodiment, the anti-vibration effect due to the ferromagnetic damping function is also obtained.

Further, the sintered anti-vibration alloy of Example 3 obtained by further recompressing the sintered anti-vibration alloy of Example 1 has a further improved logarithmic damping rate of Example 1. This is because the pores of the sintered body are crushed by the recompression process, and the graphite fine powder held in the pores is sandwiched between the inner wall surfaces of the pores, which causes the graphite fine powder and the graphite fine powder to burn. It is considered that this is because the contact area with the union increased. That is, as the contact area between the fine graphite powder and the sintered body increases, the rate at which the vibration energy applied to the sintered vibration-damping alloy is converted into the kinetic energy of the fine powder increases the damping capacity. It has improved.

Furthermore, the sintered vibration-damping alloy of Example 4 in which the raw material powder of the sintered body did not contain graphite had a further improved damping capacity compared to the sintered vibration-damping alloy of Example 3 in which graphite was contained. ing. It is considered that this is because the density after recompression processing became larger when the graphite was not contained, and the contact area between the sintered body and the fine graphite powder in the pores of the sintered body became larger.

Regarding the strength of the sintered vibration-damping alloy, the tensile strength of the flake graphite cast iron as a comparative example is 23 kgf / mm ² , whereas the strength of the sintered vibration-damping alloy of Examples 1 and 2 is Tensile strength is 4
It is ² , 31 kgf / mm ² , and it can be seen that the strength of the sintered vibration-damping alloys of Examples 1 and 2 is considerably higher than that of flake graphite cast iron. This is considered to be because, in the sintered vibration-damping alloys of Examples 1 and 2, it was not necessary to add an excessive amount of graphite at the time of powder-forming the sintered body, so that the sintering of the metal powders became stronger.

(Example 5) 2.0% by weight of copper powder, 0.2
Using raw material powder consisting of wt% carbon powder, 0.8 wt% zinc stearate, and balance iron, molding density 5.5 g / cm ³
As described above, a sintered anti-vibration alloy was manufactured by the same method as in Example 1, and then recompressed at a pressure of 7 ton / cm ² to give a density of 7.0 g / cm ³ after recompression. A sintered anti-vibration alloy was obtained.

(Evaluation 2) The sintered anti-vibration alloy of Example 5 was annealed at 300 ° C., and the relationship between the annealing holding time and the logarithmic decrement was examined. For comparison, a sintered anti-vibration alloy was produced in the same manner as in Example 5 except that graphite was not retained in the pores of the sintered body, and the same test was conducted. These results are shown in FIG. In addition, in FIG. 3, the solid line shows the test results of the sintered anti-vibration alloy of Example 5, and the dotted line shows the test results of the sintered anti-vibration alloy according to the comparison.

As is clear from FIG. 3, it is understood that the sintered anti-vibration alloy of Example 5 maintains a high damping capacity even under high temperature conditions. This is probably due to the effect of graphite partially sandwiched by the inner wall surfaces of the holes.

(Example 6) A sintered anti-vibration alloy of Example 6 was prepared by using the same material powder as that of Example 5 as the raw material powder and setting the molding density to 5.5 g / cm ³ by the same method as in Example 1 above. Got

(Evaluation 3) Regarding the sintered and vibration-isolated alloy of Example 6 recompressed while changing the repressurized surface pressure variously, the relationship between the density and the logarithmic decrement, the relationship between the repressurized surface pressure and the density, The relationship between the re-applied surface pressure and the logarithmic decrement, and the relationship between the re-applied surface pressure and the tensile strength were examined. These results are shown in FIGS.
It is shown in FIG. 6 and FIG. 7, respectively.

From this result, it can be seen that when the sintered vibration-damping alloy is densified by recompressing, both the logarithmic decrement and the tensile strength increase.

(Example 7) In Example 7, the sintered component of the present invention is applied to a gear for an automobile.

2.0% by weight of copper powder, 0.2
A raw material powder consisting of wt% carbon powder, 0.8 wt% zinc stearate, and the balance pure iron powder having a grain size of 60 to 350 mesh was mixed by a V-type mixer and compression-molded into a gear shape. At this time, as shown schematically in FIG.
The density of the strength portion 10 was 7.0 g / cm ³ and the density of the vibration isolating portion 20 was 5.8 g / cm ³ by changing the compression ratio between the tooth profile portion as 10 and the central portion as the vibration isolating portion 20. This was sintered in a mesh belt type continuous sintering furnace at 1130 ° C. for 60 minutes in a N ₂ atmosphere sintering condition. Then, a graphite fine powder having an average particle size of 1 μm
The above-mentioned sintered body was immersed in the mixed solvent consisting of 25% by weight and the balance of 75% by weight of water in the atmosphere for 2 hours to infiltrate the graphite mixed solution into the pores of the sintered body. Then, using an electric furnace, the mixture was heated at 80 ° C. for 2 hours to evaporate the water and leave only the graphite fine powder in the pores of the sintered body.
As a result, 1.1 g of graphite remained in the pores with respect to 100 g of the sintered body corresponding to the vibration isolator 20. Note that graphite did not remain in the pores of the sintered body corresponding to the strength portion 10 because the average pore diameter was small. FIG. 8 schematically shows a partially enlarged sectional view of the strength portion 10. And the vibration isolation part
Recompressed at a pressure of 10 ton / cm ² to give a recompressed density of 7.0 g / cm
As No. ³ , a sintered part of this Example 7 was manufactured.

(Example 8) In Example 8, 5.8 g of the same raw material powder as in Example 7 was used.
After compression-molding into a gear shape with a uniform density of / cm ³ , and sintering this under the same conditions as in Example 7, only 10 ton /
It was recompressed at a pressure of cm ² to a density of 7.4 g / cm ³ . Then, it was re-sintered under the same conditions as above, and the pressure-bonded surface of the strength portion 10 by re-compression was metal-bonded. Then, similarly to the above-mentioned Example 7, after the graphite fine powder was left in the pores of the sintered body, only the vibration isolator 20 was recompressed to manufacture the sintered part of this Example 8.

(Example 9) In Example 9, as in the case of Example 7, the raw material powder was compression-molded into a gear shape while changing the compression ratio of the strength part 10 and the vibration-proof part 20, and then sintered to obtain further strength. Re-compress only part 10 and strengthen part
The density of 10 was 7.6 g / cm ³ . Then, it was re-sintered in a nitrogen atmosphere at 1130 ° C. for 60 minutes to re-compress the strength portion 10 to metal-bond the pressure-bonded surface. Then, similarly to the above-mentioned Example 7, after leaving the graphite fine powder in the pores of the sintered body, only the vibration-proof part 20 was recompressed to manufacture the sintered part of this Example 9.

(Evaluation 4) With respect to the sintered parts of Examples 7 to 9 described above, the logarithmic attenuation rate and the tensile strength of the vibration isolator 20 and the strength part 10 were measured. The results are shown in Table 2.

From this result, it is understood that the higher the density of the strength portion 10, the higher the tensile strength. It should be noted that there is a limit to densification of the strength portion 10 during powder molding like the sintered part of Example 7, and it is only possible to raise the density to 7.0 to 7.2 g / cm ³ .

On the other hand, according to the recompression as in the eighth and ninth embodiments, 7.
It is possible to further increase the density to 4-7.6 g / cm ³ .

[Effects of the Invention] As described above, since the vibration energy applied to the sintered vibration-damping alloy obtained by the manufacturing method according to claim 1 is converted into the kinetic energy of fine powder, a large vibration-damping effect is thereby obtained. Obtainable. In the sintered vibration-damping alloy obtained by the manufacturing method according to claim 2, the contact area between the inner wall surface of the pores of the sintered body and the fine powder is large, and the vibration energy applied to the sintered vibration-proof alloy is fine powder. Since the rate of conversion into kinetic energy of is increased, this can obtain a greater vibration damping effect.

The sintered anti-vibration alloy obtained by the manufacturing method according to claim 1 has not only the anti-vibration effect by converting the vibration energy into kinetic energy as described above, but also a composite or ferromagnetic damping mechanism. The anti-vibration effect using can be obtained.

That is, in the manufacturing method according to claims 1 and 2, when a material that is soft and has a large damping ability, such as graphite fine powder, is used as the fine powder, the graphite fine powder itself also has vibration damping characteristics. Therefore, it is possible to obtain a vibration damping effect using a composite type damping mechanism due to a difference in vibration transmission characteristics between the sintered body and the graphite fine powder.

In addition, in the manufacturing method according to claim 1 and claim 2,
A metal powder having a ferromagnetic damping mechanism, for example,
When it is formed by using an Fe-Cr-based alloy powder, it is possible to obtain a vibration damping effect using a ferromagnetic damping function.

Furthermore, in the manufacturing method according to claims 1 and 2, it is not necessary to add an excessive amount of graphite powder such as flake graphite cast iron at the time of powder molding of the sintered body, so that sintering of metal powders is weakened. No decrease in strength of the sintered body is induced.

Furthermore, the sintered component obtained by the manufacturing method according to claims 3 and 4 is made of the sintered vibration-damping alloy obtained by the manufacturing method according to claim 1 or 2, which has the above-mentioned vibration damping effect. Since the vibration-proof part is formed and the strength part having a higher strength than the vibration-proof part is formed integrally with the vibration-proof part, the vibration-proof part is required to have a partial strength while having excellent damping ability. Can be applied to.

Moreover, in the manufacturing method according to any one of claims 1 to 4, by adjusting the addition amount of the fine powder when the fine powder is mixed with water or an organic solvent, fine particles that are easily retained in the pores of the sintered body can be obtained. Since it is possible to adjust the amount of powder, and consequently the contact area between the fine powder and the inner wall surface of the pores, it is possible to easily adjust the damping factor in the sintered vibration-damping alloy.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a partially enlarged cross-sectional view of the sintered vibration-damping alloy of the first embodiment, and FIG. 2 is a partially enlarged cross-sectional view of the sintered vibration-proof alloy of the third embodiment. 3 is a graph showing the relationship between the annealing retention time and the logarithmic decrement of the sintered vibration-proof alloy, and FIG. 4 is a graph showing the relationship between the density and the logarithmic decrement. The figure is a graph showing the relationship between repressurized surface pressure and density,
FIG. 6 is a graph showing the relationship between the re-pressurized surface pressure and the logarithmic decrement, FIG. 7 is a graph showing the relationship between the re-pressurized surface pressure and the tensile strength, and FIG. 8 is a graph showing the sintered part of Example 6. FIG. 9 is a diagram schematically showing a front view, and FIG. 9 is a diagram schematically showing a partially enlarged cross-sectional view of the strength portion. 1 ... Sintered body, 2 and 2 '... holes 3 ... (graphite) fine powder 10 ... Strength part, 20 ... Vibration isolation part

Claims (4)

[Claims] 1. A step of causing water or a mixed solvent of fine powder mixed with an organic solvent to permeate into the pores of a sintered body formed by sintering a metal powder and having the pores in a heated or depressurized state. And a step of allowing the fine powder to remain in the pores by evaporating the water or the organic solvent as described above. 2. After the fine powder remains in the pores of the sintered body, at least a part of the sintered body in which the fine powder remains in the pores is compressed or rolled. Claim 1
A method for producing the sintered vibration-proof alloy as described. 3. A vibration-damping part made of a sintered vibration-damping alloy composed of a sintered body formed by sintering a metal powder and having pores, and a fine powder held in the pores of the sintered body. A method for producing a sintered component, comprising a strength portion formed of a high-density metal sintered body having a higher density than a sintered body that is integrally formed with the vibration-proof portion and that constitutes the vibration-proof portion. , A mixture of fine powder mixed with water or an organic solvent in the pores of the low-density portion of the sintered body composed of the high-density portion partially increased in density and the low-density portion other than the high-density portion After permeating the solvent, by heating or depressurizing the water to evaporate the water or the organic solvent, the fine powder is allowed to remain in the pores of the low density portion to form the vibration isolation portion. A method for producing a characteristic sintered part. 4. After leaving fine powder in the pores of the low density portion, at least a part of the low density portion of the sintered body in which the fine powder remains in the pores is compressed or rolled. The method for manufacturing a sintered part according to claim 3, wherein