KR910003898B1 - Rubbing material for cu - Google Patents

Abstract

A rubbing material is manufactured by sintering the admixed powder consisted of 51-90.5 wt.% Cu, 4-10 wt.% Sn, up to 6 wt.% Pb, 0.5- 10 wt.% C, 5-16 wt.% Al2O3, up to 7 wt.% SiO2. The material is used as brake lining or clutch facing and supplies very stabilized frictional force in water or oil.

Description

Cu base alloy friction material

1 is a graph showing a change in the friction coefficient (μ) and wear rate (ω) according to the temperature change of the preferred embodiment of the present invention.

2 is a graph showing the oil-in-charge characteristic of the coefficient of friction with increasing speed of the preferred embodiment of the present invention.

3 is a graph showing the drying and underwater characteristics of the coefficient of friction with increasing speed of the preferred embodiment of the present invention.

The present invention relates to a small alloy friction material, and more particularly to a small alloy friction material capable of stably providing a very large braking force.

Asbestos has been mainly used as a friction material used in brake lining and clutch facing. Asbestos is not very braking and the problem of asbestos pollution such as lung cancer and asbestosis is very serious. As a result, it is being banned.

In addition, the so-called semi-metallic friction material made by mixing metal powders with plastics and resins has emerged, which is superior to asbestos, but has a braking force for use in brakes that require a large braking force such as medium, aircraft, and train. There are many problems such as insufficient size of the device, insufficient performance in water or oil, and instability in frictional inferior temperature.

In addition, a so-called metallic friction material sintered by adding C to Cu-based bearing alloys also appeared.Brake force and temperature stability are superior to conventional asbestos or semi-metallic friction materials, but are not so remarkable. There was a drawback that it was so economical that it had very limited use.

Accordingly, an object of the present invention is to provide a small alloy friction material that can exhibit a large braking force to solve the problems of the prior art described above and exhibit sufficient economic feasibility, is stable at temperature, and has a very poor performance in water or in water. .

The composition of the Cu-based small alloy friction material according to the present invention is shown in Table 1 below.

TABLE 1

<Table 1> Composition of the Cu-based small alloy friction material according to the present invention

Table 2 shows a preferred embodiment of the Cu-based small alloy friction material of the present invention configured according to the above composition.

TABLE 2

TABLE 2 Preferred Embodiments of the Invention

Method for producing a small alloy friction material of the present invention having the above composition is as follows.

First, each component powder is mixed and mixed to be sufficiently mixed, cold-formed at a suitable pressure to a density of 5.0 to 5.8 / cm ³ , and then sintered by heating for 5 to 100 minutes at a reducing atmosphere of 780 to 820 ° C., and sizing ), And other necessary processing is completed by adjusting the dimensions and shape without changing the density.

The test values obtained as a result of the braking test of the sintered alloy friction material of the present invention made by the above composition and manufacturing method were compared with those of the conventional friction material to prepare for the following <Table 3>.

TABLE 3

<Table 3> Comparison of braking force per unit area

This result is because the friction coefficient (μ) of asbestos or semi-metallic in the prior art was about 0.1, but the high coefficient of friction coefficient of 0.25 to 0.48 of the sintered alloy friction material of the present invention can be obtained. Although the damage to the friction counterpart is damaged, the present invention is easy to mix and mix appropriate friction stabilizers with respect to the friction counterpart (cast iron, cast steel, ordinary steel, and special steel), so that the damage of the friction counterpart can be reduced. Its suitability is very good. That is, in order to prevent damage of the relative friction side by the sintering alloy friction material of the present invention having a large friction coefficient, the sintering alloy friction material can be manufactured so that ordinary lead or carbon, which is a friction stabilizer, is present at the site where the friction is to be caused. In order to manufacture such a sintered body, first, in injecting the material into the moldings of the sintered body, first, a powdery stabilizer is mixed with the material of the sintered body in an appropriate ratio, and the small-bonded material obtained therefrom is first applied to a site where a frictional part is to be formed. The remaining portion is infused with a material that does not contain these stabilizers. Subsequently, compression molding and sintering are performed.

In addition, the conventional friction material is unstable with respect to temperature (especially frictional heat) and could not exert a large braking force due to the frictional heat generated during braking. As shown in FIG. The frictional force does not decrease much because the decrease of the frictional force is small. The frictional force is almost stable even when a so-called temper color is generated in the friction steel on the other side of the frictional steel.

In addition, the increase in the wear rate ω due to the increase in temperature is not as remarkable as in the conventional friction material (see FIG. 1), and the decrease in the friction coefficient due to the increase in pressure or frictional speed is also very small (see FIG. 3).

In particular, the characteristic advantages of the sintered alloy friction material of the present invention, which is not found in the conventional friction material, include water and water characteristics. The friction coefficient such as asbestos is significantly reduced in water or in water. In the present invention, as shown in FIG. 3, the low-alloy friction material of the present invention shows that the friction coefficient in water (spraying state of FIG. 3) maintains 90% or more of the dry friction coefficient. The recovery characteristics are very excellent and there is almost no change in the coefficient of friction in oil, which provides very stable friction (see Figure 2).

As such, the present invention can provide a very large coefficient of friction and thus a coefficient of friction per unit area, which is very stable against temperature (friction heat) and environment (in water and in water). It can be used as a brake for devices (medium, train, airplane), and can be miniaturized to increase the space efficiency and downsizing of the whole device, which is economically advantageous, and can provide reliable braking. The effect is great.

In addition, it is also excellent in compatibility with the friction partner side does not damage the friction partner or generate an unpleasant friction sound or odor when braking, there are many advantages that can prevent asbestos pollution, which is a serious problem in the prior art.

Claims (3)

Raw materials of 51 to 90.5% Cu, 4 to 10% Sn, 0 to 6% Pb, 0.5 to 10% C, 0.5 to 10%, 5 to 16% Al ₂ O ₃ and 0 to 7% SiO ₂ Sintered alloy friction material, characterized in that the mixture was sintered respectively. The small alloy friction material according to claim 1, wherein Cu is 74%, Sn is 8%, C is 8%, and Al ₂ O ₃ is 5%. 2. The small alloy friction material according to claim 1, wherein Cu is 70.5%, Sn is 6%, C is 0.5%, Al ₂ O ₃ is 16%, and SiO ₂ is 7%.

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