JPH076039B2 - Fe-based sintered alloy transmission synchronization ring - Google Patents

Description

TECHNICAL FIELD The present invention relates to a Fe-based sintered alloy transmission synchronizing ring having high strength, excellent wear resistance, and compatibility with a mating member. is there.

[Conventional technology]

Conventionally, generally, a transmission synchronizing ring is subjected to intermittent surface contact under high surface pressure with a tapered cone whose inner surface 1 rotates, as shown in a perspective view in FIG.
Since the chamfers 2 provided at predetermined intervals along the outer edge thereof have a function of engaging with the chamfers of the hub sleeve, it is required to have strength, wear resistance, and compatibility with a mating member. High-strength brass having these characteristics is often used in its manufacture. In addition to the above, there is a so-called pin type of synchronizing ring in which a screw is provided on the outer peripheral side and rubs against a mating taper cone on the outer peripheral side.

[Problems to be solved by the invention]

However, in recent years, demands for higher output and lighter weight of transmissions have become strict, and accordingly, further higher strength, wear resistance, and conformability have also been required for the synchronizing ring. However, the current situation is that conventional high strength brass products cannot sufficiently cope with this.

[Means for solving problems]

Therefore, the inventors of the present invention have conducted research to develop a transmission synchronization ring that can sufficiently meet the above-mentioned requirements, and as a result, the weight% (hereinafter,% relating to the component composition is the weight% Shown), one or more of Mn, Cr, and Mo: 0.1 to 6
%, C: 0.1 to 0.9%, and, if necessary, one or two of Ni and Cu: 0.1 to 6%, and B: 0.
02-0.5%, a composition containing either or both, and 0.05-
A hard Ni-P compound layer was formed on at least the tapered cone friction surface of the Fe-based sintered alloy body having a porosity of 5% by volume.
The Fe-based sintered alloy transmission synchronizing ring formed with an average layer thickness of ~ 80 μm has high strength, excellent wear resistance, and compatibility with the mating member. We have obtained the knowledge that it can sufficiently cope with higher output and lighter weight.

Next, the reasons why the composition and porosity of the synchronizing ring of the present invention and the average layer thickness of the Ni-P compound layer are limited as described above will be explained.

A. Component composition (a) Mn, Cr, and Mo These components improve strength and toughness,
Improves wear resistance and further reacts with a part of the Ni-P compound layer to improve seizure resistance, and these components are easily oxidizable, so wear due to microscopic oxidation phenomenon during practical use. However, if the content is less than 0.1%, the desired effect cannot be obtained. On the other hand, if the content exceeds 6%, further improvement effect cannot be obtained. Since it does not appear, considering economy,
Its content was set to 0.1-6%.

(B) CC component has an effect of improving strength and wear resistance, but if its content is less than 0.1%, the desired effect cannot be obtained on the other hand, while its content exceeds 0.9%. Toughness decreases, and cracks due to impact are more likely to occur,
Since the opponent's aggressiveness will also increase, the content was set to 0.1 to 0.9%.

(C) Ni and Cu These components have the effect of improving the strength, wear resistance and conformability, so they are contained as necessary, but if the content is less than 0.1%, they are desirable for the above-mentioned action. However, even if the content exceeds 6%, no further improvement effect can be obtained.
It was set at ~ 6%.

(D) BB The B component has an effect of improving the toughness and strength as well as improving the sinterability, so it is contained as necessary. However, if the content is less than 0.02%, the desired effect is improved in the above function. If the effect is not obtained and the content exceeds 0.5%,
Since the toughness is reduced, its content is 0.02
It was set at ~ 0.5%.

Although Si, S, and P components are contained as unavoidable impurities, if these components exceed 0.5% in total, strength and toughness will decrease, so the total amount will be The content must be 0.5% or less.

B. Porosity The voids in the alloy serve as oil reservoirs during practical use, in particular to improve the initial conformability of the inner surface of the ring and prevent cohesive wear of these, as well as permeation of the Ni-P compound layer. Has the effect of increasing the thickness of the layer, improving wear resistance, and forming a thin oxide film on the pore surface to normalize wear, but the ratio is 0.05% by volume. If it is less than the above range, the desired effect cannot be obtained. On the other hand, if the ratio exceeds 5% by volume, the strength decreases and it cannot be used for practical use. Therefore, the ratio is set to 0.05 to 5%.

C. Average layer thickness of Ni-P compound layer If the average layer thickness is less than 3 μm, desired excellent wear resistance cannot be ensured for a long period of time. On the other hand, if the average layer thickness exceeds 80 μm, toughness is obtained. Therefore, the average layer thickness is determined to be 3 to 80 μm.

〔Example〕

Next, the synchronizing ring of the present invention will be specifically described by way of examples.

As raw material powder, graphite powder, Cu powder, Fe powder, Mo powder, Mn powder, Ni powder, Fe-B alloy (B: 12% content) powder, Fe-Mn alloy (Mn) each having a particle size of 200 mesh or less : 3
0% content) powder and Fe-Cr alloy (Cr: 15% content) powder were prepared, and these raw material powders were each compounded to the compounding composition shown in Table 1 and mixed under normal conditions. ton
Press molding the green compacts with a pressure of / cm ²
After pre-sintering at a predetermined temperature within the range of 700 to 900 ° C, some of these pre-sintered bodies are warmed and re-pressurized using a pressure within the range of 6 to 8 ton / cm ² (first 1 In the remarks column of the table, the presence or absence of re-pressurization is displayed), and then the pre-sintered body and the re-pressurized pre-sintered body are subjected to ammonia decomposition gas at a predetermined temperature within the range of 1000 to 1200 ° C. Sintered under the condition of holding for 1 hour to form a sintered body having substantially the same composition as the compounded composition, and a part of these sintered bodies has a temperature within the range of 800 to 1000 ° C. Hot forged at temperature (No. The presence or absence of hot forging is displayed in the remarks column of Table 1), and as a result, the various porosities shown in Table 1 are also set.
Electroless plating is performed by immersion in a 90 ° C plating solution to form a Ni-P compound layer having the same average layer thickness as shown in Table 1 only on the inner surface, and finally within the range of 350 to 450 ° C. To the temperature of
By performing heat treatment under the condition of holding for 0.5 hour, the first
The shape and inner diameter shown in the figure: 58 mmφ × thickness: 8 mm, and the outer surface changer: 32 synchronization rings for a transmission made of the present invention Fe-based sintered alloy (hereinafter referred to as the present sintered ring) 1 22 and comparative Fe-based sintered alloy transmission synchronization rings (hereinafter referred to as comparative sintered rings) 1 to 6 were manufactured.

The comparative sintered rings 1 to 6 have the same composition as any one of the composition, the porosity, and the average layer thickness of the Ni-P compound layer (marked with * in Table 1). It is out of the range.

Next, regarding the various sintered rings obtained as a result,
The resistance force was measured for the purpose of evaluating the strength, and the number of revolutions of the counterpart cone, the taper cone: 1000 rpm, the material of this taper cone: the carburized and quenched material of SCM21, the pressing load: 100 kg, the oil: No. 90 mesh Oil, oil temperature: 120 ° C, taper cone operation mode: 1 second push and 2 second release, cycle: 6000 cycles, single wear test, and taper cone speed: 1200r.pm, taper cone Pressing load: 50 kg, mating material taper cone and hub sleeve material: S
CM-21 carburized and hardened material, synchronization time: 0.3 seconds to 0.4 seconds (number of times: 50,000 times), oil: No. 90 mixture oil, oil temperature: 70 ° C, bench test was conducted under the conditions of the former single unit In the wear test, the ring has cracks, the maximum wear of the ring's taper cone friction surface (hereinafter referred to as the inner surface), and the maximum wear of the mating material (the maximum wear is all standard products for measuring the amount of depression). Was prepared, and the amount of the drop was shown.), The presence or absence of seizure on the inner surface of the ring, the friction coefficient of the inner surface of the ring (up to 500 times) and the latter period (stable phase), and the presence of initial wear on the inner surface of the ring. In the latter bench test, the presence or absence of abnormal wear of the fabric and the presence or absence of abnormal sound during synchronization were measured. The results are shown in Table 2.

〔The invention's effect〕

From the results shown in Table 2, the present invention sintered rings 1 to 22
Have high strength and are excellent in wear resistance and conformability, on the other hand, comparative sintered rings 1 to 6
As can be seen from the above, when any of the constituents is out of the scope of the present invention, it is clear that at least one of the above characteristics becomes inferior. Needless to say, the same result can be obtained with a pin type synchronizing ring.

As described above, since the Fe-based sintered alloy transmission synchronizing ring of the present invention has high strength, excellent wear resistance, and compatibility with a mating member, the transmission has high output and light weight. Therefore, it is possible to fully satisfy the requirements for thinning and downsizing.

[Brief description of drawings]

 FIG. 1 is a perspective view illustrating a transmission synchronization ring. 1 …… Tapered cone friction surface (inner surface), 2 …… Changhua.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F16D 23/06 K

Claims (4)

[Claims] 1. A composition containing one or more of Mn, Cr, and Mo: 0.1 to 6%, C: 0.1 to 0.9%, and the balance Fe and unavoidable impurities (more than wt%). ), And a Fe-based sintered alloy body having a porosity of 0.05 to 5% by volume, and a hard Ni-P compound layer having an average layer thickness of 3 to 80 μm formed on at least the tapered cone friction surface of the body. Synchronous ring for sintered transmission made of sintered alloy. 2. One or more of Mn, Cr, and Mo: 0.1 to 6%, C: 0.1 to 0.9%, and one or two of Ni and Cu. : 0.1 to 6%, the balance consisting of Fe and unavoidable impurities (more than wt%), and a porosity of 0.05 to 5% by volume on at least the taper cone friction surface of the Fe-based sintered alloy body. , A Fe-based sintered alloy transmission synchronizing ring formed by forming a hard Ni-P compound layer with an average layer thickness of 3 to 80 μm. 3. One or more of Mn, Cr, and Mo: 0.1 to 6%, C: 0.1 to 0.9%, and further B: 0.02 to 0.5%. A hard Ni-P compound layer is formed on at least the taper cone friction surface of the Fe-based sintered alloy body having the composition of the balance of Fe and inevitable impurities (above wt%) and the porosity of 0.05 to 5% by volume. A synchronization ring for a transmission made of a Fe-based sintered alloy, which is formed with an average layer thickness of ~ 80 μm. 4. One or more of Mn, Cr, and Mo: 0.1 to 6%, C: 0.1 to 0.9%, and one or two of Ni and Cu. : 0.1 to 6%, B: 0.02 to 0.5%, the balance consisting of Fe and unavoidable impurities (there is more than weight%), and a porosity of 0.05 to 5% by volume 2. A Fe-based sintered alloy transmission synchronizing ring for transmission, comprising a hard Ni-P compound layer having an average layer thickness of 3 to 80 μm formed on at least the taper cone friction surface.