JP3019442B2 - Aluminum-based composite disk rotor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-load disk rotor used for a brake of an automobile or an industrial machine, and more particularly to a disk rotor having improved friction coefficient and high-temperature strength.

[0002]

2. Description of the Related Art Conventionally, in order to improve the heat resistance and wear resistance of the above-mentioned light-load aluminum or aluminum alloy disk rotor, ceramics and the like are applied to an aluminum substrate by various methods. However, attempts have not been made to obtain a composite having a high friction coefficient and excellent strength (particularly high-temperature strength).

[0003]

In view of the foregoing, the present invention has been studied in various ways. When aluminum is compounded with reinforcing particles such as ceramics, the particle size of the reinforcing particles is increased even if the reinforcing particles having the same volume ratio are compounded. Smaller ones are better in both room temperature and high temperature strength than those with larger particle size, but found that the coefficient of friction would be reduced, and as a result of further examination, it was excellent in heat resistance and wear resistance, In addition, an aluminum-based composite disk rotor having a high coefficient of friction has been developed.

That is, the present invention provides an aluminum or aluminum alloy disk rotor in which a sliding surface portion is formed of a composite material containing reinforcing particles having a particle size of 10 to 500 μm in an amount of 10 to 90 vol. , And part or all of the part other than the sliding surface
0.1 to 10 μm and contained in the sliding surface portion
Characterized in that it is formed of a composite material containing 10 to 50 vol.% Of reinforcing particles having a particle size smaller than that of the reinforcing particles.

[0005]

According to the present invention, the main purpose of the present invention is to improve the friction coefficient rather than the strength of the sliding surface portion of the conventional aluminum disk rotor. Alternatively, a high friction coefficient is given by using a composite material with an aluminum alloy powder. Parts other than the sliding surface are formed of a composite material of reinforcing particles having a smaller particle diameter and aluminum or aluminum alloy powder with emphasis on improving strength, particularly high-temperature strength. The reinforcing particles include iron, copper,
One or more kinds of metal powder such as brass and ceramic powder such as silicon carbide, titanium carbide, silicon nitride, and alumina are used. Also, the content of the reinforcing particles is
The reason why the volume ratio is set to 10 to 90 vol.% Is that if it is less than 10 vol.%, There is no effect of improving the friction coefficient, and if it exceeds 90 vol.%, Molding becomes impossible. And for parts other than the sliding surface,
The reason for setting it to 50 vol.% Is that if it is less than 10 vol.%, There is no effect of improving the high temperature strength, and if it exceeds 50 vol.%, The tensile strength sharply decreases.

Next, the manufacturing method of the present invention will be described in more detail with reference to the drawings. An aluminum alloy disk rotor coarse shape material (1) as shown in FIG. 1 is manufactured by a method such as a molten metal forging method or a sheet metal press.
Among them, the sliding surface part that improves the coefficient of friction by compounding
(2) and a strength-improved part that improves strength by compounding
(3) Applying machining to secure the installation place of the composite material. The aluminum powder and the reinforcing particles are mixed (the type, particle size and volume ratio are appropriately selected according to the required characteristics) and stirred. Alternatively, if necessary, this mixed powder is subjected to pressure molding at room temperature to prepare a preform. As shown in FIG. 2, the mixed powder (4) or the preform (5) of the mixed powder is placed on a predetermined sliding surface portion (2) and a strength improving portion (3), respectively. The composite powder (4) or the preform (5) of the composite powder is heated to a semi-melting temperature range and held, and is subjected to pressure molding to form a composite (6) as shown in FIG. Thereafter, post-processing such as machining, heat treatment, and surface treatment and finishing are performed as necessary, as in the related art.

Next, an embodiment of the present invention will be described.

EXAMPLE Using a casting aluminum alloy AC4C, a disk rotor-shaped crude material (1) as shown in FIG. 1 was produced by a casting method. At this time, a space (sliding surface portion (2)) for attaching the following composite material is left in the sliding surface portion of the rotor with the mating friction material, and the mounting surface portion of the rotor to the shaft is strong. Machined as an improvement (3). Next, aluminum alloy AC4C powder and silicon carbide particles having an average particle size of about 40 μm were mixed at a volume ratio of 20% and pressed at room temperature to form a formed body (preformed body L20), and similar silicon carbide particles Were mixed at a volume ratio of 50% and pressed at room temperature to form a molded body (preliminary molded body L50).
Further, aluminum alloy AC4C powder and silicon carbide particles having an average particle size of about 3 μm were mixed at a volume ratio of 20% and pressed at room temperature to form a molded body (preformed body S20). A preform (S50) was prepared by mixing at a volume ratio of 50% and press-forming at room temperature to form a formed body. Then, the preform L20 is set on the sliding surface portion (2) of the crude material (1), and the preform S is mounted on the strength improving portion (3).
20 was heated in a high-frequency induction heating furnace to the above-mentioned half-melting temperature of AC4C, and this crude material was set in a preheated mold, followed by pressure molding to produce a product A of the present invention. . Further, the preform L50 is set on the sliding surface portion (2) of the rough shaped material (1), and the preform S50 is set on the strength improving portion (3). Invention B was produced.
Thereafter, the above-formed pressure-formed crude material was subjected to T6 treatment and machined into a predetermined shape to produce a disk rotor.

The disk rotor of the present invention and a comparative disk rotor described below were subjected to a friction test under the conditions shown in Table 1, and the characteristics of each were compared.
It was shown to. That is, the comparison disk rotor is made of aluminum alloy AC.
Silicon carbide particles having an average particle size of about 3 μm
%, And the product manufactured by compounding the entire disk rotor by a casting method is referred to as a comparative product A. Also, aluminum alloy AC4C is mixed with silicon carbide particles having an average particle diameter of about 40 μm by 20% by volume and mixed in the same manner. The composite was designated as Comparative Product B.

[0009]

[Table 1]

[0010]

[Table 2]

From Table 2, it can be seen that the disk rotor of the present invention has a higher average friction coefficient under the same conditions than the comparative disk rotor under all the same conditions.
Further, with respect to the wear amount of the rotor, under the same conditions, the present invention product has a smaller wear amount than the comparative product. Also, the sliding surface properties of the product of the present invention were less rough and good surface properties than the comparative product. Comparative product A had a particularly small coefficient of friction because the particle size of the reinforcing particles was small, and comparative product B was inferior in high-temperature strength because the particle size of the reinforcing particles was large, and the mounting holes buckled.

[0012]

As described above, according to the present invention, the sliding surface portion of the disk rotor and the other mounting portions that require strength, for example, are made of a composite material in which the particle size of the reinforcing particles is changed. Therefore, the sliding surface portion has a high coefficient of friction, and the mounting portion subjected to a high load has high strength at a high temperature.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a disk rotor coarse material.

FIG. 2 is a side sectional view showing a state where a mixed powder of aluminum and reinforcing particles or a preform thereof is attached to a disk rotor coarse material.

FIG. 3 is a side cross-sectional view showing a state in which a mixed powder of aluminum and reinforcing particles or a preform thereof is attached to a disk rotor coarse material or a preform of the same, and is pressure-formed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Disc rotor coarse material 2 Sliding surface part 3 Strength improvement part 4 Mixed powder 5 Preform

Claims (1)

(57) [Claims] An aluminum or aluminum alloy disk rotor having a sliding surface portion having a particle size of 10 to 500 μm.
Is formed from a composite material containing 10 to 90 vol.% Of aluminum or aluminum alloy powder with respect to aluminum or aluminum alloy powder, and a part or all of the part other than the sliding surface has a particle size of 0.1 to 10 μm .
And the reinforcing particles contained in the sliding surface portion
An aluminum-based composite disk rotor characterized in that it is formed of a composite material containing 10 to 50 vol.% Of reinforcing particles having a small particle diameter with respect to aluminum or aluminum alloy powder.