JPH08170668A - Aluminum group compound material disk rotor - Google Patents

Abstract

PURPOSE: To improve brake noise resistance of an aluminum group compound material disk rotor used as a brake device for a relatively light load in an automobile or the like. CONSTITUTION: An aluminum group compound material disk rotor is integrally formed with a surface layer part of a sliding surface part as an aluminum group compound material and the inside of the sliding surface part as an aluminum alloy in the disk rotor for a disk brake, further to provide a cavity in a boundary surface between the surface layer part and the inside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc rotor for a disc brake of automobiles, railway vehicles, industrial machines, etc.
In particular, it relates to an aluminum-based composite disc rotor for relatively light loads.

[0002]

2. Description of the Related Art Cast iron is generally used as the disc rotor of the disc brake. However, the cast iron rotor has a problem that it is easily rusted and brake noise is generated. Therefore, various disk rotors made of an aluminum-based composite material have been tried to solve the former problem, but the latter problem of noise has not always been solved.

[0003]

As a result of studies in view of these problems, the present invention has improved brake noise resistance in a disk rotor using an aluminum-based composite material.

That is, in one of the disk rotors of the present invention, the surface layer of the sliding surface of the disk rotor for disk brake is made of aluminum-based composite material, and the inside of the sliding surface is integrally formed of aluminum alloy, and It is characterized in that a void is provided on the boundary surface between the surface layer portion and the inside.

Another aspect of the disk rotor of the present invention is that a pair of annular plates made of an aluminum-based composite material having protrusions and concave portions coated with graphite are formed on one surface of the disc-shaped circular plate, and the other surfaces of the annular plates are directed inside. It is characterized in that it is made of aluminum alloy and cast on one side thereof as a sliding surface.

[0006]

As described above, according to the present invention, the surface layer portions of the rotor sliding surfaces on both sides of the disk rotor are different in material from the inside sandwiched by the both surface layer portions, and the boundary surface between the surface layer portion and the inside is different. By providing the air gap, vibration energy at the time of braking is absorbed at this boundary surface, so that brake noise is less likely to occur. Further, as described above, the surface layer portion is made of an aluminum-based composite material and the inside is made of an aluminum alloy, so that the sliding surface has excellent heat resistance and wear resistance, and the other portions have toughness and machinability. The material is integrated by selecting materials having characteristics suitable for each part such as good. Further, by providing the projections on the inner side surface of the aluminum-based composite material which becomes the surface layer portion of the sliding surface portion, it is possible to improve the bonding strength of the surface layer portion when the aluminum alloy composite is cast.

Next, the manufacturing procedure of the disk rotor of the present invention will be described. As the aluminum-based composite material on the surface layer of the sliding surface of the disk rotor, a composite material in which reinforcing particles such as ceramics are added and dispersed in an aluminum alloy is used.

First, the above-mentioned aluminum-based composite material is produced by a method such as high pressure casting, powder forging or infiltration method to prepare a rough shaped material B shown in FIG. 1 having a shape corresponding to the surface layer portion of the rotor sliding surface. This rough material B has an annular shape that is a sliding surface of the rotor,
A plurality of protrusions (1) and a plurality of shallow recesses (2) are formed on one surface thereof. Further, the flat surface portion (3) on this one side and the surface of the protrusion (1) are coated with Cu, Ni or the like so as to facilitate bonding during the following casting, and the concave portion (2)
The inside is coated with graphite so that it will not be filled with the aluminum alloy during casting. Next, two pieces of this rough material B, a movable mold (6) and a fixed mold (7) connected to a movable cylinder (5) of a mold (4) for a disk rotor cast doll as shown in FIG. At the position of the surface layer portion of the sliding surface portion between them, the one surfaces on which the projections (1) and the like are formed are installed so as to face each other inward. An aluminum alloy is poured into the mold (4) by a molten metal sleeve (8) and a pressure punch (9), and the rough forged material B is cast to form an entire rotor rotor shape product A by a molten metal forging method. . Thereafter, this A is subjected to a cutting process or the like in a usual process to obtain a finished product of the disk rotor.

[0009]

EXAMPLES The present invention will now be described in detail with reference to Examples.

Al having excellent heat resistance with solidus temperature of 653 ° C.
-8 wt% Fe alloy powder mixed with 30 wt% alumina particles was charged into a mold for molding the surface layer shape of the rotor sliding surface shown in Fig. 1, up to the semi-melting temperature range where some liquid phase occurs. After heating and holding, pressure was applied to fabricate a crude material B. The 16 concave portions (2) on one side of the rough material B were thickly coated with graphite and dried, and the 8 projections (1) and the flat surface portion (3) other than the concave portion (2) were sprayed with Cu. . Next, as shown in FIG. 2, a pair of the above-mentioned rough shape materials B are opposed to each other at the positions where the projections (1) are formed at the positions corresponding to the surface layer portions of the sliding surface portions of the molten metal forging die (4) for disk rotor casting. Let me set it,
A rotor-shaped product A is obtained by pouring and pressurizing (casting) a molten aluminum alloy (AC4C) into the mold (4). After that, the unnecessary portion was removed, and an aluminum-based composite disc rotor with a regular size was obtained by cutting.

The disc rotor of the present invention was combined with an ordinary disc brake to perform a braking test, and the noise generation rate was investigated. The results are shown in Table 1 together with the damping rate of the rotor. The comparative rotor shown in Table 1 is the one in which the entire rotor shape is made only by the aluminum-based composite material in which 20 wt% of SiC is added to the Al-9 wt% Si alloy by the casting method. The comparative rotor is a conventional cast iron rotor. .

[0012]

[Table 1]

[0013]

As described above, according to the present invention, the aluminum-based composite disc rotor is further excellent in the brake noise resistance, and it is possible to reduce the weight and improve the quality of the brake device for automobiles. It has an effect.

[Brief description of drawings]

FIG. 1 shows a surface layer portion of a sliding surface portion of a disk rotor of the present invention, (a) is a plan view and (b) is a sectional view taken along line XX ′ of (a).

FIG. 2 is an explanatory view showing an example of a method of making a cast rotor of a disk rotor of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Protrusion 2 Recess 3 Flat part 4 Mold 5 Movable cylinder 6 Movable mold 7 Fixed mold 8 Molten metal sleeve 9 Press punch

Claims (2)

[Claims] 1. A surface layer part of a sliding surface part of a disk rotor for a disk brake is made of an aluminum-based composite material, and an inside of the sliding surface part is integrally formed as an aluminum alloy, and a boundary surface between the surface layer part and the inside is formed. An aluminum-based composite disk rotor characterized by having voids. 2. A pair of annular plates made of an aluminum-based composite material having a projection and a recess coated with graphite formed on one surface of an aluminum alloy with one surface facing inward and the other surface sliding on each other. Aluminum-based composite disc rotor characterized by being cast.