KR20120010732A - Brake disk for vehicle and manufacturing method of it - Google Patents

Abstract

PURPOSE: A brake disk for a vehicle and a manufacturing method thereof are provided to cast different materials into a single product with reduced costs and time. CONSTITUTION: A brake disk for a vehicle comprises a friction plate(10b) made from grey cast iron and a disk hat(10a) made from spheroidal graphite cast iron. The friction plate comprises carbon(C) 3.1~3.6 weight%, silicon(Si) 2.1~2.7 weight%, manganese(Mn) 0.4~0.7 weight%, phosphorus(P) 0.05~0.1 weight%, sulfur(S) 0.01~0.10 weight%, chrome(Cr) 0.02~0.3 weight%, copper(Cu) 0.05~1 weight%, tin(Sn) 0.001~0.1 weight%, and iron(Fe) of the remaining amount. The disk hat comprises carbon(C) 3.1~3.6 weight%, silicon(Si) 2.1~2.7 weight%, manganese(Mn) 0.4~0.7 weight%, phosphorus(P) 0.05~0.1 weight%, sulfur(S) 0.01~0.10 weight%, nickel(Ni) 0.05~4 weight%, magnesium(Mg) 0.15~1.0 weight%, and iron(Fe) of the remaining amount.

Description

Brake disk for vehicle and manufacturing method thereof

The present invention relates to a brake disc for automobiles and a method for manufacturing the same, and more particularly, to a brake disc for automobiles and a method for manufacturing the same, which are made of different materials to satisfy both torque resistance and heat dissipation performance.

Each wheel of the disc brake type vehicle is combined with a brake disc to rotate like a wheel, and the disc rotated with the wheel is selectively brought into close contact with the brake pad to provide braking force to the vehicle through the frictional force.

Referring to the conventional brake disc with reference to FIG. 1, the brake disc 1 is composed of a disk hat 1a and a friction plate 1b integrally molded.

The disc hat 1a has a through hole 4 in the center thereof, and a plurality of fastening holes are formed in the circumferential direction around the through hole 4, so that the disc hat 1a is fastened to the fastening bolt 3. By the wheel (not shown).

The disc hat 1a is coupled to the drive shaft 2 by a spline, and transmits the rotational force of the drive shaft 2 to the wheel.

The friction plate 1b is continuously formed integrally along the outer diameter portion of the disk hat 1a by the wall portion 1c, and is selectively compressed by the brake pad while rotating together with the disk hat 1a. The friction forces the vehicle to brake.

However, the conventional manufacturing method of the brake disc does not lead to efficient braking by integrally manufacturing the disc hat 1a and the friction plate 1b by using a single material (for example, FC material, a kind of cast iron). There was a point.

This is because the disk hat 1a is repeatedly and momentarily torqued from the drive shaft 2, and is always receiving the tightening compression force due to the bolting with the wheel, so that the strength and the durability are improved, and the friction plate 1b is Since friction heat is generated due to friction with the brake pad, an improvement in heat radiation performance is required.

Therefore, it is difficult to simultaneously satisfy the torque oral cavity and heat dissipation performance required when the brake disc 1 is made of one material.

Invented in view of such a point, the present applicant has filed a patent application on June 20, 2008, published 10-2009-0132172 to cast the disc hat and the friction plate of the brake disc integrally so as to suit each characteristic Disclosed are brake discs composed of different materials.

However, in the disclosed patent, gray molten iron (FC) molten metal and spheroidal graphite iron (FCD) molten metal are different from each other in the manufacture of the brake disc, and thus, the two molten metals need to be prepared separately.

The present invention was invented in view of the above disadvantages, by improving the preparation of two types of molten metal separately in the manufacture of a conventional brake disc, by determining the composition range of the basic molten iron by using both gray cast iron and nodular graphite cast iron, It is an object of the present invention to provide a brake disc for automobiles and a method for manufacturing the same which can reduce the manufacturing time and reduce the manufacturing time.

In order to achieve the above object, the present invention is common in gray cast iron and spheroidal graphite iron, carbon (C) 3.1 ~ 3.6% by weight, silicon (Si) 2.1 ~ 2.7% by weight, manganese (Mn) 0.4 ~ 0.7 weight %, 0.05 to 0.1% by weight of phosphorus (P), 0.01 to 0.10% by weight of sulfur (S), and a residual amount of iron (Fe) and other unavoidable impurities are prepared. Cr) 0.02 to 0.3% by weight, copper (Cu) 0.05 to 1% by weight, tin (Sn) 0.001 to 0.1% by weight to form a gray cast iron friction plate;

And dissolving 0.05 to 4% by weight of nickel (Ni) and 0.15 to 1.0% by weight of magnesium (Mg) in the remainder of the basic molten metal to form a disc hat of spherical graphite cast iron. It provides a method for producing a brake disc for a vehicle, characterized in that it can be used simultaneously with the molten nodular cast iron.

According to the brake disc for a vehicle and a method for manufacturing the same according to the present invention, by forming a basic molten iron that can satisfy the properties of gray cast iron and nodular cast iron in common, to form a gray cast iron and nodular cast iron molten metal at the same time By using it, it is possible to reduce manufacturing costs and shorten manufacturing time when casting dissimilar materials into a single piece.

1 is a cross-sectional view showing a disc brake system according to the prior art
2 is a cross-sectional view showing a brake disc according to the present invention.
Figure 3 is a photograph showing the microstructure of each part of the brake disk according to the present invention

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view showing the brake disc 10 according to the present invention.

The present invention relates to a method for manufacturing a brake disc (10) using a cast iron composition for the brake disc (10) which can determine the composition range of the base molten metal and simultaneously use gray cast iron (FC) and nodular cast iron (FCD). will be.

The dissimilar material of the brake disc 10 includes a disk hat 10a of a nodular cast iron material, a friction plate 10b made of gray cast iron, and a wall portion 10c in which the nodular cast iron and gray cast iron are fused together. And they are cast into a single body.

A pad is in contact with the friction plate 10b to provide friction and braking force, and a bolting hole 180 is formed in the disc hat 10a to be combined with a wheel (not shown), and the wall portion 10c is the disc hat 10a. And the friction plate 10b are connected stepwise.

The disc hat 10a may use spherical graphite cast iron FCD400 to FCD700 (JS standard).

Spheroidal graphite cast iron is a spheroidized graphite and ferrite matrix structure that gray cast iron does not have, and it guarantees 10% elongation and excellent strength compared to gray cast iron. Suppresses the occurrence of cracks when tightening.

The friction plate 10b may use gray cast iron FC150 to 250 (JS standard).

Gray cast iron can maintain high friction due to high Mn content, maintains wear resistance during braking due to pearlite matrix structure, and has excellent relative vibration damping ability.

In addition, the gray cast iron has a length of graphite and its shape is so-called A type, and serves to effectively release the braking heat generated during braking due to the formation of the A-type graphite to the atmosphere.

3 is a view showing the microstructure of each part of the brake disc, where (a) shows a friction plate 10b, (b) shows a wall portion 10c, and (c) shows a disk hat.

The friction plate 10b is composed of gray cast iron, the particles are dense and sharp, and the wall portion 10c has a connective structure in which gray cast iron and spheroidal graphite iron are fused.

The disc hat is composed of nodular cast iron, and spheroidized graphite is observed, and the spherical graphite can maintain high strength compared to gray cast iron.

The wall portion 10c is a point at which gray cast iron and nodular graphite iron are fused to each other, and the interface between the components is not sharply formed.

The composition of the basic melt is carbon (C) 3.1-3.6 wt%, silicon (Si) 2.1-2.7 wt%, manganese (Mn) 0.4-0.7 wt%, phosphorus (P) 0.05-0.1 wt%, sulfur (S) It is composed of 0.01 to 0.10% by weight and the balance of iron (Fe) and other unavoidable impurities.

Here, in order to implement the required properties and microstructure of gray cast iron, the FC molten metal contains 0.02 to 0.3 wt% of chromium (Cr), 0.05 to 1 wt% of copper (Cu), and 0.001 to 0.1 wt% of tin (Sn). It is further comprised.

And, in order to implement the required properties and microstructure of the nodular cast iron, the FCD molten metal is further included in the basic molten metal (Ni) 0.05 ~ 4% by weight, magnesium (Mg) 0.15 ~ 1.0% by weight.

The content of the basic molten metal, FC molten metal, FCD molten metal and reason for addition are as follows.

(1) Carbon (C) 3.1 ~ 3.6 wt%

If the carbon is less than 3.1% by weight, it is difficult to produce the graphite shape of the cast iron structure of the A type, and when it exceeds 3.6% by weight is difficult to use simultaneously with the molten FCD500 material, in the present invention, it is limited to 3.1 to 3.6% by weight.

(2) silicon (Si) 2.1 ~ 2.7 wt%

If silicon is less than 2.1% by weight, it is difficult to produce A type flake graphite of size 3 or more of FC200 gray cast iron, and if it exceeds 2.7% by weight, coarse C-type kishy graphite precipitates and the strength of FCD500 material may be reduced. Therefore, the present invention is limited to 2.1 to 2.7% by weight.

Here, the C and Si contents are determined as 4.1 to 4.35 based on the carbon equivalent (represented as a relationship between the three characters of CC; C and Si or P, and used for judging strength, predicting thickness sensitivity, etc.), and indicating strength and hardness. Set the range so that the physical properties do not drop sharply.

(3) Manganese (Mn) 0.4 ~ 0.7 wt%

When the manganese is less than 0.4% by weight, there is a difficulty in shortening the heat treatment time when the bainite phase is generated, and when the weight is 0.7% by weight or more, since workability is lowered due to tissue hardening, it is limited to 0.4 to 0.7% by weight.

(4) 0.05 to 0.10 wt% of phosphorus (P)

Phosphorus is an element forming the Fe ₃ P compound, and is present as a three-step process steadite together with ferrite and iron carbide. If the phosphorus content is too high, there is a problem of lowering the tensile strength.

(5) Sulfur (S) 0.01 ~ 0.10 wt%

When sulfur is less than 0.01% by weight, it is difficult to promote spheroidization by generating MgS by reacting with magnesium (injectable material) (possible gray cast iron), and there is a problem of spheroidization due to excessive MgS, and brittleness due to FeS formation when exceeding 0.10% by weight. Therefore, in the present invention, it is limited to the range of 0.05 to 0.10% by weight.

(6) Chromium (Cr) 0.02 to 0.3 wt%

Cr inhibits graphitization, as opposed to Ni or Si, and is added to enhance the stabilizing action of iron carbide. Cr is too much to inhibit graphitization and degrades castability.

(7) Copper (Cu) 0.05 ~ 1 wt%

Copper acts to densify the ferrite structure of cast iron. If the copper content is too high, brittleness becomes strong due to excessive increase in hardness.

(8) Tin (Sn) 0.001 to 0.1 wt%

Tin densifies the ferrite structure of cast iron, and adding too much tin increases strength and hardness, but becomes brittle.

(9) Nickel (Ni) 0.05-4 wt%

Nickel is added to refine the grains to increase the known toughness, and when the nickel content exceeds 4 wt%, brittleness becomes strong.

(10) Magnesium (Mg) 0.15 ~ 1 wt%

Magnesium is added for spheroidization of graphite and is limited to 0.15 to 1% by weight in the present invention because its effect is less than 1% by weight.

Hereinafter, the manufacturing method of the brake disc 10 according to the present invention will be described.

First, in order to satisfy FC / FCD in common, 3.1 to 3.6 wt% of carbon (C), 2.1 to 2.7 wt% of silicon (Si), 0.4 to 0.7 wt% of manganese (Mn), and 0.05 to 0.1 wt% of phosphorus (P) Prepare a basic molten metal composed of 0.01 to 0.10 wt% of sulfur (S), and remaining iron (Fe) and other unavoidable impurities.

Then, a part of the basic melt prepared according to the hardness and strength requirements to satisfy the composition of the FC melt, 0.02 to 0.3 wt% of chromium (Cr), 0.05 to 1 wt% of copper (Cu), and 0.001 to 0.1 wt of tin (Sn). After dissolving% in the above composition range in an FC injector or a heating furnace to form a gray cast iron, the gray cast iron is injected into a mold to form a friction plate 10b of FC150 to FC 250.

Then, in order to satisfy the composition of the FCD molten metal, the remaining basic molten metal and 0.05 to 4% by weight of nickel (Ni) and 0.15 to 1.0% by weight of magnesium (Mg) were dissolved in the FCD injector or a heating furnace. After forming a nodular cast iron molten metal, this nodular cast iron molten metal is further injected into a mold to form a disc hat 10a.

At this time, in the wall portion 10c connecting the friction plate 10b and the disk hat 10a, gray cast iron and nodular graphite cast iron are mixed to form an unsharp interface between the components.

Therefore, by simultaneously using the basic melt having the composition range in the casting of the brake disc 10 of the dissimilar materials (FC and FCD), it is not necessary to prepare the FC and FCD molten metal separately, thereby reducing costs and shortening the manufacturing time You can.

Hereinafter, the present invention will be described in more detail by the following examples, but the present invention is not limited by the following examples.

Example

Table 1 shows the composition and content of cast iron used in the production of the brake disc 10 of different materials according to the present invention and a single material according to the prior art, and Table 2 shows the effects (strength / hardness and heat dissipation performance, etc.) of the present invention. Represents the data.

Using the material of the composition and content shown in Table 2 above, in the case of the embodiment by using the method of manufacturing a brake disc 10 of the heterogeneous material according to the present invention, by applying a method of manufacturing a brake disc of a single material according to the prior art in the comparative example Brake disks were manufactured, and then the strength, hardness, and heat dissipation performance were measured, and the results are shown in Table 2.

10: brake disc 10a: disc hat
10b: Friction plate 10c: Moon portion

Claims (2)

3.1 to 3.6 wt% of carbon (C), 2.1 to 2.7 wt% of silicon (Si), 0.4 to 0.7 wt% of manganese (Mn), 0.05 to 0.1 wt% of phosphorus (P), 0.01 to 0.10 wt% of sulfur (S), Friction plate made of gray cast iron (10b) consisting of 0.02 to 0.3% by weight of chromium (Cr), 0.05 to 1% by weight of copper (Cu), 0.001 to 0.1% by weight of tin (Sn), and residual amounts of iron (Fe) and other unavoidable impurities )and;
3.1 to 3.6 wt% of carbon (C), 2.1 to 2.7 wt% of silicon (Si), 0.4 to 0.7 wt% of manganese (Mn), 0.05 to 0.1 wt% of phosphorus (P), 0.01 to 0.10 wt% of sulfur (S), A disk hat 10a of spheroidal graphite cast iron composed of 0.05 to 4% by weight of nickel (Ni), 0.15 to 1.0% by weight of magnesium (Mg), and a residual amount of iron (Fe) and other unavoidable impurities;
Brake disk for automobiles comprising a.
3.1 to 3.6 wt% of carbon (C), 2.1 to 2.7 wt% of silicon (Si), 0.4 to 0.7 wt% of manganese (Mn), 0.05 to 0.1 wt% of phosphorus (P), 0.01 to 0.10 wt% of sulfur (S), And preparing a basic molten metal composed of a residual amount of iron (Fe) and other unavoidable impurities;
A friction plate 10b was formed by injecting a gray cast iron melt formed by dissolving 0.02 to 0.3 wt% of chromium (Cr), 0.05 to 1 wt% of copper (Cu), and 0.001 to 0.1 wt% of tin (Sn) in a part of the basic molten metal. Forming a;
Injecting a spherical graphite cast iron melt formed by dissolving 0.05 ~ 4% by weight of nickel (Ni), 0.15 ~ 1.0% by weight of magnesium (Mg) in the remaining basic molten metal used in the above step to form a disk hat (10a) Method for producing a brake disc for automobiles, characterized in that comprises a.

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