KR101491167B1 - Brake disc and manufacturing method thereof - Google Patents

Abstract

A method of manufacturing a brake disc and a brake disc in which a disc hats and a friction plate are integrally cast is introduced. This method of manufacturing a brake disk includes a friction plate forming step of injecting gray cast iron to form a friction plate, and a disk hat forming step of casting the disk hat by injecting spheroidal graphite cast iron. After the gray cast iron is injected, When the temperature of the region is maintained between 1000 and 1200 ° C, the spheroidal graphite cast iron is injected to cast the disk hats and the friction plate integrally.

Disk hats, friction plates

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a brake disk,

More particularly, the present invention relates to a brake disk capable of increasing the strength of engagement at the interface between the gray cast iron of the friction plate and the spheroidal graphite cast iron of the disk hats, and a brake disk And a manufacturing method thereof.

The braking device is a device for decelerating or stopping a running vehicle or for keeping a stopped vehicle in a stopped state.

The braking device includes a braking force generating device for generating a force necessary for braking, a braking device for reducing or stopping the vehicle by using the force generated by the braking force generating device, a pipe for transmitting the force of the braking force generating device to the braking device, Valves, and ancillary equipment for auxiliary power. The braking system is structurally divided into drum type brakes and disc type brakes.

In the case of the disc type brake, a brake disc is fixed to each wheel of the vehicle, and a pair of brake pads are provided on the left and right surfaces of the brake disc, which can be pressed or separated from each other. That is, when the brake pad is brought into close contact with the brake disk rotated together with the wheel, the vehicle is braked through the frictional force.

As shown in FIG. 4, the conventional brake disk will be briefly described. The disk 10 is largely composed of a disk hat 11 and a friction plate 12. The disc hats 11 are coupled to the knuckle portion 20 of the vehicle wheel and are rotatable as the wheels and the ends of the disc hats 11 are provided with a friction plate 12 and can be rotated as the drive shaft of the wheel. When the friction plate 11 on which the brake pads (not shown) rotate is pressed, the frictional force is applied to the vehicle.

Such conventional brake discs may be manufactured by casting a disc hatch and a friction plate as a separate piece and then using the same, or by using a single material even if the disc hats and the friction plate are integrally cast.

However, when the disk hats and the friction plates are made of a separate material, there is a problem that the number of assembling operations is increased and the braking force is lost. When the disc hats and the friction plates are integrally cast, the disc hats and the friction plates have different roles, and a certain tie is required in terms of performance and durability, so that efficient braking can not be realized.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide a brake disk and a method of manufacturing the brake disk for preventing separation of heterogeneous materials generated at the interface between the gray cast iron of the friction plate and the spheroidal graphite cast iron of the disk hats.

According to another aspect of the present invention, there is provided a method of manufacturing a brake disc in which a friction disc including a disc head and a lower end of a disc head is cast in a cavity, Molding step; And forming a disk hat by injecting spheroidal graphite cast iron. When the temperature of the interface portion between the spheroidal graphite cast iron and the spheroidal graphite cast iron after the casting of the gray cast iron is maintained between 1000 and 1200 ° C, And the disc hats and the friction plates are integrally cast.

In particular, after injecting the gray cast iron, it is preferable to perform air cooling so that the temperature of the interface portion is cooled to 1000 to 1200 ° C., and the mold type is preferably an upper mold in which spheroidal graphite cast iron is injected for molding the disk hats, And a lower mold into which the gray cast iron is injected so as to form a friction plate that covers the lower end of the lower mold.

The brake disk according to the present invention includes a friction plate that is molded by injecting gray cast iron, and a disk bat which is formed integrally with the friction plate by injecting spheroidal graphite cast iron when the temperature of the interface between the friction plate and the friction plate is maintained between 1000 and 1200 ° C do.

According to the present invention, when the temperature of the interface portion of the gray iron with respect to the spheroidal graphite cast iron satisfies a certain range, there is an advantage that the bonding strength of the brake disk can be improved by injecting the spheroidal graphite cast iron and realizing the bonding between them .

In addition, the present invention can reduce the NVH while securing the product characteristics by applying the gray iron to the friction plate, simplifying the number of parts of the brake disk by constituting the disk hats and the friction plate as one body, There is an advantage in that the strength and rigidity can be increased by applying cast iron.

In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the brake disk according to the present invention includes a friction disk formed with gray iron, and a disk hat molded by injecting spheroidal graphite cast iron into a friction plate having an interface region temperature of 1000 to 1200 ° C. Structure. At this time, a wall 130 is formed between the disk hats 110 and the friction plate 120, where the spheroidal graphite cast iron and the gray iron are intermixed with each other.

Such a disk hat 100 is coupled to a knuckle portion (not shown) through a bolt hole 140 and the friction plate 120 is formed in the shape of a disk covering a lower end portion of the disk hat 110, ).

The disc hats 100 are made of spheroidal graphite cast iron and the friction plate 120 is made of gray cast iron. The spheroidal graphite cast iron is suitable for the material of the disc hats 110 because it can withstand the torque durability generated during braking and can suppress cracking during the direct fastening of the steel material bolts. It is suitable as the material of the friction plate 120 because high frictional force can be maintained. In the present embodiment, the spheroidal graphite cast iron is FCD500 (JS standard) and the gray iron is FC200 (JS standard).

Particularly, in the state where the friction plate 120 is molded by the gray cast iron injected into the lower mold 220, the interface region temperature of the friction plate 120, that is, the interface region temperature at which the connection with the disk hat 110 is made is 1000 to 1200 The coupling between the disk hats 110 and the friction plates 120 is realized while the disk hats 110 are molded by injection of the spheroidal graphite cast iron.

At this time, if the temperature of the interface portion is less than 1000 占 폚, the solidification of pre-casted gray cast iron melt proceeds excessively, and the interface of the spheroidal graphite cast iron to be post-injected is remelted, so that heterogeneous materials are separated from the interface between gray cast iron and spheroidal graphite cast iron May occur. On the other hand, if the temperature of the interfacial region is higher than 1200 ° C., the spheroidal graphite cast iron is injected before the initiation of solidification of the molten pre-cast metal It is difficult to realize the unique characteristics of each of the gray iron and the spheroidal graphite cast iron because it is mixed with the disc hats, hubs and friction surfaces. Therefore, it is preferable to maintain the interface temperature of the gray cast iron contacting the spheroidal graphite cast iron at 1000 to 1200 ° C, and the size of the brake disk suitable for the temperature is about 220 to 260 mm.

Hereinafter, a method of manufacturing a brake disk according to the present invention will be described.

First, an upper mold 210 for forming the disk hats 110 and a lower mold 220 for forming the friction plates 120 are prepared. A cavity is formed between the upper mold 210 and the lower mold 220 so that the disk hats 110 and the friction plates 120 can be integrally cast.

When the upper mold 210 and the lower mold 220 are prepared, the gray cast iron is injected into the lower mold 220 through the gray iron inlet 310. The reason why the gray cast iron is injected before the spheroidal graphite cast iron is that the gravity casting of the gray cast iron is based on this embodiment. Therefore, when the spheroidal graphite cast iron is first injected, the position of the injection port must be moved to the center.

The gray cast iron introduced into the lower mold 220 is filled in the friction plate cavity portion 222 and the wall cavity portion 223 to form the friction plate 120 and the wall 130.

When the inflow of the gray iron into the lower mold 220 is completed, air is cooled so that the interface region temperature of the gray iron to be brought into contact with the spheroidal graphite cast iron is maintained between 1000 and 1200 ° C. At this time, it is preferable to take a stand, and it may take 30 to 120 minutes. The reason why the temperature of the interface portion must satisfy 1000 to 1200 占 폚 is the same as that described above.

When the interface temperature of the gray iron reaches 1000 to 1200 ° C, the spheroidal graphite cast iron is injected into the upper mold 210 through the spheroidal graphite iron inlet 320.

When the spheroidal graphite cast iron is injected into the upper mold 210 and the disk hats 110 are formed and the spheroidal graphite cast iron and the gray iron are mutually fused and connected to each other at the wall 130, Respectively.

An embodiment using the above-described method of manufacturing a brake disk will be described.

Table 1 shows the composition ratios of the gray cast iron and the spheroidal graphite cast iron of the specimens produced according to the present invention, and Table 2 shows the mechanical properties of the specimens produced. The mechanical properties include the tensile strength and hardness of the specimen produced by the present invention.

[Table 1]

C Si Mn P S Cr Cu Sn Mg Gray cast iron
(FC200) 3.7 1.6 0.7 0.1 or less 0.15 or less 0.3 0.35 0.04 Spheroidal graphite cast iron
(FCD500) 3.7 2.5 0.5 0.05 or less 0.01 or less 0.1 or less 0.35 - 0.35

[Table 2]

division The tensile strength
(N / mm ² ) Hardness (HB) Spheroidal graphite cast iron (FCD) surface Hwang Ju Chul (FC) Psalm 1 312 179 193 203 Psalm 2 291 174 193 203

As shown in FIG. 3, tensile test was performed using the prepared specimen. As a result, it was confirmed that the portion broken by the tensile force was a portion of the gray iron rather than the portion where the bonding interface was located.

As a result, when spheroidal graphite cast iron is injected and bonded at a temperature of the interface region of the gray cast iron to be contacted with the spheroidal graphite cast iron at a temperature of 1000 to 1200 ° C, the gray cast iron and the spheroidal graphite cast iron are completely bonded to each other, It can be seen that the bonding strength is increased.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the present invention is not limited to the disclosed exemplary embodiments. It will also be appreciated that many modifications and variations will be apparent to those skilled in the art without departing from the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a configuration diagram showing a brake disk according to the present invention. Fig.

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a brake disk manufacturing method.

FIG. 3 is a photograph showing a tensile test of a specimen manufactured according to the method of manufacturing a brake disk according to the present invention. FIG.

4 is a configuration diagram showing a brake disk according to the related art;

※ Refer to the explanation of the main parts of the drawing ※

100: Brake disk 110: Disk hat

120: friction plate 130: month

210: upper mold 220: lower mold

Claims (4)

1. A method of manufacturing a brake disc in which a friction plate that covers a lower end portion of a disc head and a disc head is cast in a mold- A friction plate forming step of injecting gray cast iron to form a friction plate; And And a disk-hat shaping step of casting the disk hat by injecting spheroidal graphite cast iron, Characterized in that the spherical graphite cast iron is injected to coalesce the disk hats and the friction plate while maintaining the temperature of the interface portion between the spheroidal graphite cast iron and the spherical graphite cast iron after the disk hats are cooled to between 1000 and 1200 ° C, Gt; delete The brake of claim 1, wherein the mold comprises an upper mold into which spheroidal graphite cast iron is injected for forming the disk hats, and a lower mold into which gray cast iron is injected to form a friction plate that winds the lower end of the disk hats. A method of manufacturing a disk. A friction plate molded by injecting gray cast iron; When the temperature of the interface region of the friction plate to be contacted is maintained between 1000 and 1200 캜, spheroidal graphite cast iron is injected and mixed with spheroidal graphite cast iron and gray iron; And And a disk-shaped disk made of a spheroidal graphite cast iron, which is integrally formed with the friction plate through the wall.

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