JPS63238248A - Synchronous ring made of cu alloy for gearbox - Google Patents

Abstract

PURPOSE:To obtain a synchronous ring for gearbox excellent in initial conformability and wear resistance, by constituting the above ring of an alloy having a composition consisting of Zn, Al, Ti, Zr, Fe, Ni, Co and Cu and also by forming a work-hardened layer of a specific layer thickness on a working surface. CONSTITUTION:The synchronous ring for gearbox is constituted of a Cu alloy which has a composition consisting of, by weight, 20-40% Zn, 2-8% Al, 0.1-3% Ti and/or Zr, 0.1-4% of one or more elements among Fe, Ni, and Co, and the balance Cu with inevitable impurities and further containing, if necessary, 0.1-5% Mn. Further, a work-hardened layer is formed to 5-300mum average layer thickness on the required part of the working surface, against opposite members, of the above synchronous ring by means of a shot blasting method, etc. By this method, the synchronous ring made of Cu alloy for gearbox combining high strength with high toughness, excellent in initial conformability at the above working surface, free from abnormal wear, such as bright-surface wear and adhesive wear, and capable of showing superior wear resistance over a long period can be obtained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention provides a synchronous ring for a transmission made of a Cu-based alloy, which has excellent initial conformability of the contact surface with a mating member and excellent wear resistance. It is related to.

[Conventional technology]

Conventionally, a synchronizing ring for a transmission generally has an inner surface 1 that is a contact surface with a rotating tapered cone, and a tapered cone that is a mating member on this contact surface, as illustrated in a perspective view in FIG. Surface contact is made intermittently under high surface pressure, and on the other hand, a key groove 3 into which a key fits is formed on the outer peripheral surface, and chamfers 2 provided at predetermined intervals along the outer edge of the hub sleeve are also mating members. Since it has the function of interlocking with the changua of the metal, it is required to have strength, wear resistance, and compatibility with the mating material, so high-strength brass with these characteristics is often used in its manufacture. There is. In addition, there is also a so-called pin type synchronizing ring, which has a thread on the outer circumferential side and rubs against a tapered cone, which is a mating member, on the outer circumferential side.

[Problem that the invention seeks to solve]

However, as the output of transmissions has increased in recent years, the above-mentioned conventional high-strength brass synchronizing ring has been particularly affected by contact with at least one of the above-mentioned taper cones, keys, and hub sleeve changers. This is because the bottom surface will be subjected to high surface pressure.

Initial conformability deteriorates, and this causes frequent abnormal wear due to bright surface wear and adhesive wear, leading to a shortened service life.

[Means for solving problems]

Therefore, the present inventors conducted research to solve the problems of the conventional high-strength brass synchronizing ring for transmissions as described above, and as a result, Zn was added at 1% by weight (hereinafter, ``chi'' indicates % by weight). :20-40%, A1. =2-8%.

One or more of Ti and Zr: 0.1 to 3%, Fe%Ni, and one or more of two or more of Co: 0.1 to 4%.

Contains, and if necessary, Mn:O, 1-5%, and Sn: 0.1-3%.

It is made of a Cu-based alloy containing one or two of the following, and the remainder is Cu and unavoidable impurities. The contact surface of at least one of the mating parts of the hub sleeve's chang-a
Synchronizing rings for transmissions made of U-alloy exhibit excellent initial conformability even under conditions of use under high surface pressure associated with higher output of transmissions, and the occurrence of abnormal wear in the early stages of use is suppressed. We obtained this knowledge.

This invention has been made based on the above knowledge, and the reason why the component composition and the average layer thickness of the work-hardened layer are limited to the above-mentioned values will be explained.

(a) Zn and M These components determine the base structure of the alloy, improve the wear resistance of the base, provide the strength and toughness necessary for the synchronous ring, and further improve fatigue strength. It has excellent yield strength and is essential for forming a work-hardened layer on the ring surface that prevents adhesion (seizure) due to plastic flow caused by local high-temperature heating, thereby preventing abnormal initial wear and improving initial conformability. However, if the content is less than 20% and A2:2%, it will not be possible to ensure the above properties, and it will be difficult to form a work-hardened layer with the above properties. On the other hand, its content is Zn:
If the content exceeds 40% and fiJl: 8%, the toughness will decrease, so the content should be adjusted to Zn: 20 to 40%.
%, Ag: 2 to 8%.

(b) Ti and Zr with F'e, Ni, and c.

Ti and/or Zr and one or more of Fe%Ni and Co are melted to form an intermetallic compound that is finely dispersed in the base material, thereby achieving the strength and toughness required for the synchronous ring. It has the effect of improving wear resistance without impairing it, but if the content is less than 0.1%, the desired effect cannot be obtained; on the other hand, if the content is less than 3% and 4%, respectively If the amount exceeds υ, the amount of intermetallic compounds will be too large and the machinability will deteriorate.
Fe, Ni.

Regarding CO, it was set at 0.1 to 4 inches.

(c) Mn The Mn component has the effect of forming a solid solution in the base material and strengthening it, as well as making intermetallic compounds into fine spherules, thereby improving wear resistance, so it may be included as necessary. If the content is less than 0.1%, the desired effect of improving the above action cannot be obtained, and on the other hand, if the content exceeds 5%, no further improvement effect is obtained, but rather the generation of slag during melting. Since the content increases, the content is set at 0.1 to 5%.

(d) The 5n Sn component has the effect of preventing adhesive wear and ensuring excellent anti-seizure properties, so it is included as necessary, but the content should be less than 1%. In this case, the desired effect of improving the above-mentioned action cannot be obtained.

On the other hand, if the content exceeds 3 inches, hot workability deteriorates, so the content was set at 0.1 to 3 inches.

In addition, unavoidable impurities such as P, Pb, and even Mg may be contained, but if the total amount of these unavoidable impurities is 1% or less, they will not affect the characteristics in any way, so the total amount The content is allowed within the range of 1% or less.

(e) Work-hardened layer The work-hardened layer can be formed by shot blasting or sandblasting as described above, or if it is provided only on the friction surface of the taper cone of the ring, for example, it cannot be pressed by cold pressing using a steel die. It can be formed by processing, etc., and the work-hardened layer formed in this way has excellent fatigue strength and yield strength due to its component composition, so it is suitable for localized high-temperature heating. As a result, seizure and other problems are suppressed, thereby preventing abnormal initial wear and exhibiting excellent initial wear resistance. However, if the average layer thickness is less than 5 μm, the desired On the other hand, even if the average layer thickness exceeds 300 μm, excellent effects cannot be ensured, so the average layer thickness was set at 5 to 300 μm.

〔Example〕

Next, the synchronization ring of the present invention will be specifically explained using examples.

Using an ordinary high-frequency furnace, CU-based alloy melts having the compositions shown in Table 1 were prepared, and mold casting was carried out.
Form a billet with diameter: 200mφ x length: 4001ull, and extrude this billet into a diameter: 60B using an extrusion press.
After extruding into a round bar of φ and cutting this round bar to a predetermined length, the cut pieces are hot forged at a temperature within the range of 600 to 750°C, further cut, and then exposed to air. Inside,
Using mixed beads of SiC beads and steel beads (SiC: 5°0% by volume) with a diameter of 10 to 300 μm, shot blasting was performed to form a work-hardened layer with the average layer thickness shown in Table 1. By forming on the entire surface, synchronous rings 1 to 21 of the present invention and comparative synchronous rings 1 to B, each having dimensions of inner diameter = 58 Bφ x thickness = 4 mm and number of chamfers: 36, were manufactured. .

In addition, Comparative Synchronous Rings 1 to 8 have any of the conditions (those marked * in Table 1) of the component composition and the average layer thickness of the work-hardened layer that are outside the scope of the present invention. .

Next, regarding the various synchronous rings obtained as a result, the rotation speed of the tapered cone as the mating member: 1200 r-p
-m・1 Pressing load: 55 to 9b Oil: No. 80 transmission oil, oil temperature near 5℃, taper cone operation = 20,000 times with synchronization time of 0.2 to 0.3 seconds, synchro durability test under the following conditions. The amount of depression (amount of wear) on the inner surface of the ring, and the presence or absence of adhesive wear.

The initial (up to 500 times) and late (stable period) friction coefficients were measured and observed, and the number of rotations of the tapered cone, which was the mating member: 2000 r, p, m, and the pressing load: 9 kg.

Oil: No. 80 mission oil, Oil temperature near 0℃.

Taper cone operation: A synchro durability test was conducted 5,000 times with a synchronization time of 0.25 to 0.3 seconds under the following conditions, and the presence or absence of cracks and deformation in the ring was observed. These results are shown in Table 1.

[Effects of the Invention] From the results shown in Table 1, it can be seen that the synchronization rings 1 to 21 of the present invention
Both have high strength and toughness, and exhibit excellent conformability in the initial stage of practical use, no abnormal wear, and excellent wear resistance, even under high surface pressure conditions. As seen in Comparison Synchronization Rings 1 to 8, it is clear that if any of the constituent requirements falls outside the scope of the present invention, at least one of the above characteristics will be inferior. . It goes without saying that similar results can be obtained with a pin-type synchronous ring.

As mentioned above, the synchronizing ring for a transmission made of a CU-based alloy of the present invention has high strength and toughness, and has particularly excellent initial break-in properties, making it suitable for practical use under harsh conditions associated with the increase in the output of transmissions. Even during this process, there is no occurrence of abnormal wear such as bright part wear or adhesive wear, and excellent wear resistance is exhibited over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a perspective view illustrating a synchronizing ring for a transmission. 1...Tapered cone friction surface (inner surface). 2...Chang 7a, 3...Keyway.

Claims (4)

[Claims] (1) Zn: 20-40%, Al: 2-8%, one or two of Ti and Zr: 0.1-3%, one or two of Fe, Ni, and Co. that's all:
0.1 to 4%, and the rest is Cu and unavoidable impurities (weight %), and a work hardening layer is provided at required locations on the contact surface with the mating member. 5~300μ
A synchronizing ring for a transmission made of a Cu-based alloy and formed with an average layer thickness of m. (2) Zn: 20-40%, Al: 2-8%, one or two of Ti and Zr: 0.1-3%, one or two of Fe, Ni, and Co. that's all:
0.1 to 4%, and further contains Mn: 0.1 to 5%, and the remainder is Cu and unavoidable impurities (weight%), and Apply a work-hardening layer of 5 to 300 μm at the required locations on the contact surface with the mating member.
A synchronizing ring for a transmission made of a Cu-based alloy and formed with an average layer thickness of m. (3) Zn: 20-40%, Al: 2-8%, one or two of Ti and Zr: 0.1-3%, one or two of Fe, Ni, and Co. that's all:
0.1 to 4%, and further contains Sn: 0.1 to 3%, and the remainder is Cu and unavoidable impurities (weight %), and Apply a work-hardening layer of 5 to 300 μm at the required locations on the contact surface with the mating member.
A synchronizing ring for a transmission made of a Cu-based alloy and formed with an average layer thickness of m. (4) Zn: 20-40%, Al: 2-8%, one or two of Ti and Zr: 0.1-3%, one or two of Fe, Ni, and Co. that's all:
0.1 to 4%, and further contains Mn: 0.1 to 5%, Sn: 0.1 to 3%,
Composition with the remainder consisting of Cu and unavoidable impurities (more than % by weight)
A synchronous ring for a transmission made of a Cu-based alloy, which is made of a Cu-based alloy having the following properties, and has a work-hardened layer formed at required locations on the contact surface with a mating member with an average layer thickness of 5 to 300 μm.