JPH04306286A - Friction material - Google Patents

Abstract

PURPOSE:To further improve abrasion resistance and friction coefficient of a non-asbest-based friction material containing rock wool blended therewith. CONSTITUTION:A friction material composed of a fibrous base material, an additive and a binder and characterized by the composition of the fibrous base material containing a non-fibrous component-containing rock wool and 3-10wt.% content of the non-fibrous component based on weight of the rock wool.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction material used for brake pads or clutch facings of vehicles.

0002

[Prior Art] Conventionally, the properties required for friction materials are as follows:
Examples include excellent wear resistance, high friction coefficient, and stable friction coefficient. It is difficult to satisfy these performances using a single material, and friction materials are constructed as composite materials made of many materials.

[0003] In recent years, as the performance of vehicles has improved, friction materials such as brake pads and clutch facings are required to have better wear resistance and a higher coefficient of friction, and the types and composition of compounded materials are being studied. . On the other hand, asbestos, which has traditionally been valued as a cheap and useful fiber base material component, has become clear to have an adverse effect on the human body, and there is a growing movement to eliminate it from friction materials. Known fibrous base materials that can replace asbestos include heat-resistant organic fibers such as aromatic polyamide fibers, inorganic fibers such as glass fibers and ceramic fibers, carbon fibers, and metal fibers, each of which may be used singly or in combination. Friction materials that combine these have been proposed.

JP-A No. 64-55441 discloses that rock wool formed from rock having a specific composition range is mixed with one or more of steel fibers, glass fibers, and aromatic polyamide fibers to produce a fibrous base material. There is a disclosure of a friction material used as a friction material.

[0005]

[Problems to be Solved by the Invention] When a fibrous base material is prepared by blending rock wool with one or more of the above-mentioned aromatic polyamide fibers, glass fibers, and steel fibers, a non-asbestos friction material can be obtained. Can be formed. However, the obtained friction material still cannot be said to be sufficient in terms of improving wear resistance and increasing the coefficient of friction.

The object of the present invention is to provide a non-asbestos friction material containing rock wool with further improved wear resistance and friction coefficient.

[0007]

[Means for Solving the Problems] The friction material of the present invention is a friction material made of a mixture of a fibrous base material, an additive, and a binder, wherein the fibrous base material contains a non-fibrous component. It is characterized in that it contains wool, and the content of the non-fibrous component is 3 to 10% by weight based on the weight of rock wool.

The friction material of the present invention is formed by blending rock wool containing a non-fibrous component as one component of a fibrous base material. Rock wool is usually formed into a fibrous material by melting a rock component such as igneous rock and blowing the molten material with gas (air or water vapor) over a long period of time. Therefore, non-fibrous components that are not fiberized and solidified into powder or granules during production tend to be mixed in the fibrous material. Therefore, when only rock wool is used, it is necessary to separate and remove this non-fibrous material. However, depending on the fiberization conditions, it is also possible to set the content of non-fibrous components within a specific range.

Although the reason for the presence of a small amount of non-fibrous material in rock wool is unknown, when it is blended as a component of a fibrous base material, the resulting friction material has improved wear resistance and a lower friction coefficient. It has become clear that the improvement is better than when only fibrous materials are used. The amount of this non-fibrous component ranges from 3 to 10% by weight based on the total amount of rock wool. If the amount of non-fibrous content is less than 3% by weight, no improvement in the coefficient of friction will be observed, as is the case when ordinary rock wool is used. Moreover, if the amount of non-fibrous components exceeds 10% by weight, the wear rate increases, which is not preferable.

[0010] In addition to rock wool, the fibrous base material is used by adding one or more types of known fibers such as glass fibers, aramid fibers, ceramic fibers, and metal fibers. As the binding material, commonly used thermosetting phenolic resins, melamine resins, epoxy resins, etc. can be used. As additives, organic and inorganic lubricants and fillers can be used, such as cashew dust, carbon black, graphite, silica, molybdenum disulfide, calcium carbonate, magnesium carbonate, barium sulfate, and the like.

[0011] This friction material can be formed by mixing a fibrous base material, a binder, and additives and using a conventional molding method.

0012

Functions and Effects of the Invention In the friction material of the present invention, rock wool containing a specific amount of non-fibrous matter is blended as one of the components of the fibrous base material. By including this non-fibrous component, the friction coefficient and abrasion resistance are improved compared to when fibrous rock wool is added. Therefore, it can be used as a friction material for high-speed vehicles with excellent wear resistance and friction coefficient. It also does not contain asbestos, which is harmful to the human body.

[0013]

[Examples] Hereinafter, the present invention will be explained in detail using examples. Roqueurs having different contents of non-fibrous components shown in Table 1 were used.

[0014]

[Table 1] The friction materials are 10% by weight of rock wool, 8% by weight of aramid fiber, 6% by weight of brass fiber, and 5% by weight of potassium titanate fiber.
% by weight of a fibrous base material, 10% by weight of phenolic resin as a binder, 7% by weight of cashew dust, 6% by weight of graphite, 3% by weight of molybdenum disulfide, 2% by weight of silica.
, 43% by weight of barium sulfate were mixed and molded.

[0015]

[Table 2] Molding conditions are 160℃ and 400kg/cm2 in the mold.
The friction material was thermoformed for 10 minutes at a pressure of

As shown in Table 2, Example 1 uses rock wool with a non-fibrous content of 3% by weight, Example 2 uses rock wool with a non-fibrous content of 5% by weight, and Example 3 uses non-fibrous rock wool with a non-fibrous content of 5% by weight. condition is 1
0% by weight of rock wool, Comparative Example 1 had a non-fibrous content of 1% by weight.
In Comparative Example 2, rock wool with a non-fibrous content of 20% by weight was used. The other formulations are the same as above as shown in Table 2.

The friction coefficient and wear rate of each of the obtained friction materials were measured and evaluated. Friction coefficient is JASO
- According to C406-82, caliper type PD51s,
Rotor thickness: 18mm bench, inertia: 4.5kg
Measured with fmS2. Wear rate is JASO-C427-
According to 83, caliper type: PD51s, rotor: 18
mm bench, inertia; 3.5kgfmS2 5
Under the conditions of 0 → 0km/h x 0.3G, the temperature of the friction material is 10
The wear rates at 0°C, 200°C, and 300°C were measured. The results are shown in Table 3.

[0018]

[Table 3] The friction materials of Examples 1, 2, and 3, in which the rock wool contained 3 to 10% of non-fibrous content, had improved friction coefficients and wear rates. Comparative examples that do not contain non-fibrous components have relatively high wear rates but low friction coefficients. On the other hand, in Comparative Example 2 where the non-fibrous content is increased to 20% by weight, the friction coefficient is higher than Examples 1, 2, and 3, but the wear rate increases, especially as the temperature increases, and it is The wear rate is about three times that of the example. Therefore, it is shown that if the non-fibrous content in rock wool is in the range of 3 to 10% by weight, both the friction coefficient and the wear rate can be improved in a well-balanced manner.

Therefore, a friction material containing rock wool containing non-fibrous components is a friction material that does not contain asbestos, has excellent friction coefficient and wear resistance, and is effective for use in brake pads, clutch facings, etc. It is.

Claims (1)

[Claims] 1. A friction material composed of a mixture of a fibrous base material, an additive, and a binder, the fibrous base material containing rock wool containing a non-fibrous component; A friction material having a content of 3 to 10% by weight based on the weight of rock wool.