Brake disc for disc brakes and method for manufacturing a brake disc for disc brakes

Abstract

To provide brake discs that are highly resistant to corrosion and wear, less prone to delamination and interlayer break-up, and ensure thermal and mechanical performance, thereby demonstrating long-term reliability. [Solution] The brake band is made of gray cast iron or steel, and the disc has a base layer that covers at least one of the two braking surfaces of the brake band. The base layer consists of a titanium and / or titanium alloy matrix containing one carbide and defines the tribologically active surface of the disc. Alternatively, the base layer consists of a layer of titanium and / or titanium alloy, and the coating layer on top of it consists of a layer based on one or more carbides and defines the tribologically active surface of the disc. The one or more carbides are selected from the group consisting of titanium carbide, tungsten carbide, chromium carbide, niobium carbide, molybdenum carbide, and silicon carbide. An intermediate fusion layer exists at the interface between the base layer and the gray cast iron or steel brake band. The base layer has a crystalline structure, and its growth direction is mainly perpendicular to the braking surface.

Description

Technical Field

[0001] The present invention provides a disk for a disk brake and a method for manufacturing the disk for a disk brake.

Background Art

[0002] The brake disk in a vehicle's disk brake system is composed of an annular structure (brake band) and a central fixing element called a bell. Through this bell, the disk is fixed to a rotating part (e.g., a hub) of the vehicle suspension. The brake band is provided with a counter brake surface that cooperates with at least one friction element (brake pad) housed in a caliper body. This caliper body is arranged so as to straddle the brake band and is integral with a non-rotating part of the vehicle suspension. Through the controlled interaction between the opposing brake pads and the opposing brake surfaces of the brake band, a braking action due to friction occurs, decelerating or stopping the vehicle.

[0003] Generally, brake disks are made of gray cast iron or steel. In fact, with this material, relatively low cost and good braking performance (especially in terms of suppressing wear) can be obtained. Disks made of carbon or carbon ceramic materials exhibit significantly excellent performance, but the cost becomes significantly higher.

[0004] The limitation of conventional disks made of cast iron or steel is due to excessive wear. Regarding gray cast iron disks, there is also another serious problem of rust generation due to excessive oxidation of the surface. This affects both the performance and appearance of the brake disk. The rust on the brake disk is unacceptable from an aesthetic point of view for users.

[0005] This problem is particularly prominent in brake disks for electric vehicles.

[0006] In fact, electric vehicles have regenerative braking capabilities, which reduces the need for conventional braking. This means that the brake discs are exposed to atmospheric factors more frequently, either per unit of time or per unit of distance traveled.

[0007] Consequently, corrosive substances adhering to the brake surface of the brake disc remain present in greater quantities and for longer periods, increasing the likelihood of rust formation. This situation not only detracts from the appearance of the disc but also has significant negative impacts on braking performance and comfort.

[0008] One proposed solution is to paint the brake surface of the disc. However, this measure is only temporarily effective because the paint layer inevitably wears down rapidly. Furthermore, the paint layer itself reduces braking performance.

[0009] To address these issues, gray cast iron or steel discs with protective coatings have been attempted. The protective coating serves to reduce disc wear on the one hand, and on the other hand, protect the gray cast iron substrate from surface oxidation and prevent the formation of a rust layer.

[0010] Titanium and its alloys possess highly attractive properties that enable their use in many fields. Some of these properties include excellent corrosion and erosion resistance, high specific strength due to low density (enabling lightweight yet high-strength structures), heat resistance, and, in some cases, cryogenic properties.

[0011] However, titanium and its alloys also possess less-than-ideal tribological properties, such as low wear resistance, poor resistance to fatigue (fritting) wear, and a high coefficient of friction. All of these factors have significantly limited the use of titanium and its alloys in the field of mechanical engineering, particularly in brake discs.

[0012] The frictional properties of titanium stem from its crystalline structure and reactivity, and can be largely overcome by appropriate thermochemical treatments that modify the surface of the titanium substrate to increase its hardness. One of the most common thermochemical treatments for titanium and its alloys is nitriding.

[0013] To avoid the technical complexities of titanium nitriding, coatings based on titanium and titanium alloys using cold gas injection (CGS) deposition technology have been proposed, as described in EP4174212. While these coatings have been demonstrated to have corrosion resistance and wear resistance, they have a problem in that they are prone to delamination and overall peeling under usage conditions.

[0014] Currently available protective coatings applied to discs are made from particularly corrosion-resistant materials such as titanium and its alloys, providing wear resistance, but they are prone to peeling and detaching from the disc itself. Furthermore, these coatings are sensitive to thermal cracking during use and to the presence of cracks during application.

[0015] As an alternative, coatings of iron-based metals (e.g., steel) using laser metal deposition (LMD) technology have been proposed. These coatings show improved performance compared to uncoated cast iron discs. However, although the rate of delamination and interlayer breakage is lower than that of titanium or titanium alloy coatings, they do not meet the expectations for practical use. In fact, these coatings have poor corrosion resistance and only withstand salt spray tests (SST) for a few tens of hours.

[0016] Therefore, there is a particularly strong demand for gray cast iron or steel brake discs with coatings that ensure resistance to corrosion and wear, minimize delamination and break-off, guarantee appropriate thermal and mechanical performance, and demonstrate long-term reliability. [Overview of the Initiative]

[0017] Therefore, the main object of the present invention is to provide a brake disc for a disc brake to solve or at least mitigate the aforementioned problems associated with the known art. This disc is resistant to corrosion and wear, and at the same time is less likely to experience peeling or delamination, ensuring appropriate thermal and mechanical performance and demonstrating reliability over a long period of time.

[0018] A further object of the present invention is to provide a brake disc for a disc brake that is easy and inexpensive to manufacture.

[0019] A further object of the present invention is to establish a method for manufacturing a brake disc for a disc brake that is resistant to corrosion and wear and less likely to experience peeling or delamination in an easily applicable manner on an industrial scale.

Brief Description of the Drawings

[0020] The technical features of the present invention can be clearly understood from the content of the claims, and its advantages will become more readily apparent from the following detailed description made with reference to the accompanying drawings. The drawings show one or more embodiments, which are merely examples and not limiting.

[0021] - [Figure 1] FIG. 1 shows a plan view of a brake disc according to an embodiment of the present invention.

[0022] - [Figure 2] FIG. 2 shows a cross-sectional view of the disc of FIG. 1 taken along the section line II-II shown in the figure.

[0023] [Figure 3] FIG. 3 is a cross-sectional view showing an alternative embodiment of the disc of FIG. 1. It is shown along the section line II-II.

[0024] [Figure 4]Figure 4 shows a microscopic photograph of the interface region between the surface of a gray cast iron disk and the base layer deposited by the LMD technique in the disk according to the present invention. This microscopic photograph emphasizes the growth morphology of the base layer deposited by the LMD technique.

[0025] [Figure 5] Figure 5 shows a microscopic photograph of the interface region between the surface of a known type of gray cast iron disk and the titanium coating layer deposited on the disk by the CGS technique. This microscopic photograph emphasizes the growth morphology of the coating layer deposited by the CGS technique.

[0026] [Figure 6] Figure 6 shows a microscopic photograph at a higher magnification than Figure 4. In this photograph, the interface region between the surface of the cast iron disk and the base layer deposited on the disk of the present invention by the LMD technique can be confirmed in more detail. This photograph emphasizes the presence of the growth of the base layer deposited by the LMD technique.

[0027] [Figure 7] Figure 7 is an enlarged detailed view of a specific part of the microscopic photograph of Figure 6, emphasizing the presence of an intermediate mutual melting layer existing between the cast iron of the disk and the base layer deposited by the LMD technique.

[0028] [Figure 7a] Figure 7a shows the same microscopic photograph as Figure 7. Here, the contour of the intermediate fusion layer existing between the cast iron of the disk and the base layer deposited by the LMD technique is emphasized.

[0029] [Figure 8] Figure 8 shows a microscopic photograph of substantially the same region of the disk shown in Figure 7, framed. In this photograph, three different points where elemental analysis of the chemical composition was performed are shown respectively. The base layer is "spectrum 3", the intermediate fusion layer is "spectrum 4", and the gray cast iron of the brake band is "spectrum 6".

[0030] [Figure 9]Figure 9 shows the results of elemental analysis conducted at the three different locations shown in Figure 8, presented in three tabular formats. [Modes for carrying out the invention]

[0031] Referring to the figures mentioned above, 1 shows the brake disc according to the present invention as a whole.

[0032] According to a general embodiment of the invention shown in the accompanying drawings, the brake disc 1 has a brake band 2 having two opposing brake surfaces 2a and 2b. Each brake surface partially defines at least one of the two main surfaces of the disc.

[0033] The brake band 2 may be made of gray cast iron or steel.

[0034] Preferably, the brake band 2 is made of gray cast iron. Preferably, the entire disc 1 is made of gray cast iron. Therefore, although the following description refers to a gray cast iron disc, the possibility of it being made of steel is not ruled out.

[0035] The disc 1 includes a base layer 30 that covers at least one of the two braking surfaces 2a and 2b of the brake band 2. This base layer 30 is formed in direct contact with the braking surface.

[0036] As will be described later, the expression "formed in direct contact with the braking surface" means that the base layer is formed directly on the braking surface without prior deposition of an adhesive layer. Therefore, this expression also includes the possibility of forming an intermediate layer due to the metallurgical interaction between the base layer and the braking surface determined by the deposition of the base layer 30.

[0037] The base layer 30 can be any of the following:

[0038] - Consists of a titanium or titanium alloy matrix containing one or more carbides, directly defining the tribologically active surface of disk 1 (see Figure 2); or

[0039] - Consists of a layer of titanium or titanium alloy, further covered with a coating layer 300 (see Figure 3).

[0040] In this second case, the coating layer 300 consists of one or more carbide-based layers and defines the tribologically active surface of disk 1.

[0041] "A tribologically active surface" means the surface of a brake disc that is equipped with a brake system in which brake disc 1 is intended to be a component, and on which the braking action of the brake pads directly acts.

[0042] The one or more carbides are selected from the group consisting of titanium carbide (TiC), tungsten carbide (WC), chromium carbide (e.g., Cr3C2), niobium carbide (NbC), molybdenum carbide (Mo2C), and silicon carbide (SiC).

[0043] At the interface between the base layer 30 and the brake band 2 made of gray cast iron or steel, there is an intermediate fusion layer 32 having a mixed composition of the base layer 30 and the brake band 2.

[0044] The base layer 30 has a crystalline structure, and its growth direction is approximately perpendicular to the braking surface.

[0045] This can be observed using an optical microscope.

[0046] In particular, the micrograph in Figure 4 reveals the growth direction of Ti, which is almost perpendicular to the surface of the cast iron.

[0047] Microscopic images in Figures 6, 7, 7a, and 8 show the partial melting of the cast iron that led to the formation of the intermediate permeation layer, as well as the crystalline structure of the titanium substrate.

[0048] The presence of an intermediate fusion layer 32 between the base layer 30 and the brake band 2 was confirmed by performing elemental chemical composition analysis at multiple locations near the interface between the cast iron disc surface and the base layer deposited on the disc according to the present invention using LMD technology. Specifically, the elemental composition of points within the base layer, points within the intermediate fusion layer, and points within the cast iron portion of the brake band was detected. The results of these analyses are shown in the table in Figure 9. This data supports the conclusion that the intermediate fusion layer has a mixed composition of the base layer 30 and the brake band 2.

[0049] Surprisingly, it was confirmed that the base layer 30 manufactured in this way imparted corrosion resistance and wear resistance to the disc 1, and at the same time, (compared to coating with titanium or a known alloy) peeling or delamination did not occur, or if it did occur, it was only to an extremely small extent.

[0050] Therefore, the disk 1 according to the present invention ensures sufficient thermal and mechanical performance and exhibits reliability over the long term.

[0051] While not necessarily bound by this theoretical explanation, the following hypothesis has been proposed regarding the virtually non-existent occurrence of delamination and interlaminar separation.

[0052] - The intermediate fusion layer ensures an extremely stable and strong bond between the base layer 30 and the brake band. This is because it is a mutual penetration area between the two parts, and this mutual penetration resists tension in the direction parallel to the brake surface, which would otherwise cause delamination or detachment.

[0053] Similarly, because the growth direction of the crystal structure is nearly perpendicular to the braking surface, it prevents crack propagation in a direction parallel to the braking surface, which can cause delamination and chipping.

[0054] Therefore, these two properties work synergistically to suppress peeling and chipping phenomena.

[0055] In particular, these two embodiments ensure proper adhesion to the brake surface even under thermal load during braking.

[0056] The corrosion resistance stems from the presence of titanium. Specifically, the use of titanium or its alloys guarantees the following:

[0057] - Corrosion resistance for several hundred hours in salt spray testing (SST)

[0058] - Excellent resistance to high-temperature corrosion

[0059] - Good mechanical ductility

[0060] The low wear resistance of titanium is compensated for by the presence of carbides dispersed in the titanium or titanium alloy matrix constituting the base layer 30, or concentrated in the coating layer 300.

[0061] By using a titanium alloy instead of pure titanium, advantages such as improved thermal shock resistance during braking, increased hardness, extended mileage, and reduced dust emissions can be obtained.

[0062] This invention makes it possible to obtain a brake disc that combines the corrosion resistance and wear resistance of titanium, and in which peeling and flaking substantially do not occur.

[0063] Preferably, the base layer 30 is the result of a metallurgical bond formed between at least one of the brake surfaces 2a and 2b and a first particle composition deposited on the brake surfaces 2a and 2b by a laser beam deposition technique, preferably laser metal deposition (LMD) technique. The first particle composition has the same composition as the base layer 30.

[0064] In particular, the titanium alloy contains aluminum, preferably with an aluminum content of 2% or more by weight.

[0065] Advantageously, the titanium alloy also contains vanadium, preferably with a vanadium content of 1% or more by weight.

[0066] Preferably, the titanium alloy is an alloy of titanium, aluminum, and vanadium.

[0067] - Aluminum is contained in a weight content of 2% to 8%,

[0068] - Vanadium is present in a weight content of 1% to 10%,

[0069] - The remaining part of the aforementioned alloy is titanium.

[0070] The thickness of the aforementioned base layer 30 is advantageously between 5 μm and 700 μm, preferably between 50 μm and 400 μm.

[0071] As already noted, the base layer 30 may consist of a titanium substrate or a titanium alloy containing one or more carbides. In this case, the weight content of the carbides is between 2% and 80%. The wide range is due to the fact that the density of the available carbides is highly variable and this is reflected in the weight percentage. Values ​​close to 2% are due to a lower carbide density than that of titanium (Ti), while values ​​close to 80% are due to a higher carbide density than that of titanium (Ti).

[0072] The aforementioned base layer 30 may be composed of titanium alone or of the titanium alloy alone.

[0073] Advantageously, the coating layer 300 may contain at least 60% by weight, preferably at least 70% by weight, of one or more of the carbides. In this case, the remaining portion of the coating layer 300 is composed of a metal matrix (preferably iron-based or aluminum-based).

[0074] Advantageously, the coating layer 300 is obtained by:

[0075] - Thermal spraying technology, e.g., HVOF (high-velocity oxygen fuel spraying) technology, HVAF (high-velocity air fuel spraying) technology, APS (atmospheric plasma spraying) technology; or

[0076] - Cold spraying technology, for example, KM (kinetic metallization) technology; or

[0077] - Deposition technologies using laser beams, such as LMD (Laser Metal Deposition), HSLC (High-Speed ​​Laser Cladding), EHLA (Ultra-High-Speed ​​Laser Plugging), and TSC (Top-Speed ​​Cladding).

[0078] When a coating layer 300 is provided, its thickness is preferably 10 μm to 150 μm, more preferably 30 μm to 120 μm.

[0079] For the sake of explanation, the brake disc 1 will be described together with the method of the present invention. The brake disc 1 is preferably, but not necessarily, manufactured by the method of the present invention described later.

[0080] According to a general embodiment of the method of the present invention, the method includes the following operational steps.

[0081] a) Step of preparing the brake disc. The brake disc includes a brake band having two opposing brake surfaces, each brake surface partially defining at least one of the two main surfaces of the disc. The brake band is formed of gray cast iron or steel.

[0082] b) Deposition step. A first particle composition containing titanium or a titanium alloy is deposited on at least one of the brake surfaces 2a and 2b using a laser beam deposition technique, preferably LMD (laser metal deposition) technique, thereby forming a base layer 30 that covers at least one of the two brake surfaces 2a and 2b of the brake band 2.

[0083] Deposition using laser beam deposition technology, preferably LMD (laser metal deposition) technology, has the following advantages:

[0084] - At the interface between the base layer 30 and the brake band 2 made of gray cast iron or steel, an intermediate fusion layer having a mixed composition is formed between the base layer 30 and the brake band 2.

[0085] -A base layer 30 is formed that mainly has a growth direction perpendicular to the braking surface, forming a crystalline structure.

[0086] The method according to the present invention forms a tribologically active coating layer containing one or more carbides on at least one brake surface by the following two alternative methods.

[0087] a) The first particle composition deposited in step b) includes one or more of the carbides. In this case, the first particle composition consists of titanium, or a mixture of titanium and one or more titanium alloy metals, and further includes one or more of the carbides. In this case, the tribologically active coating layer is directly composed of the base layer 30.

[0088] or

[0089] b) In step c) following step b), an additional layer 300 based on one or more carbides is deposited on the base layer 30. In this case, the initial particle composition deposited in step b) consists of titanium, or a mixture of titanium and one or more titanium alloy metals. In this case, the tribologically active coating layer consists of the additional layer 300.

[0090] In both embodiments, the one or more carbides are selected from the group consisting of titanium carbide (TiC), tungsten carbide (WC), chromium carbide (e.g., Cr3C2), niobium carbide (NbC), molybdenum carbide (Mo2C), and silicon carbide (SiC).

[0091] In particular, the aforementioned titanium alloy is an aluminum alloy, preferably an aluminum alloy with an aluminum weight content of 2% or more.

[0092] Preferably, the aforementioned titanium alloy also contains vanadium, and preferably the weight content of vanadium is 1% or more.

[0093] Preferably, the titanium alloy is an alloy of titanium, aluminum, and vanadium.

[0094] Aluminum is present in a weight content of 2% to 8%,

[0095] - Vanadium is present in a weight content of 1% to 10%,

[0096] - The remaining part of the aforementioned alloy is titanium.

[0097] In particular, step b) can be carried out until a thickness of 5 μm to 700 μm, preferably 50 μm to 400 μm, is obtained relative to the base layer 30.

[0098] In accordance with method a) described above, preferably, in the first particle composition described above, the weight content of one or more carbides is between 2% and 80%.

[0099] Preferably, according to method a) described above, the first particle composition consists of titanium or titanium alloy particles mixed with the second particle composition.

[0100] More specifically, the second particle composition comprises one or more carbides.

[0101] In accordance with the method described above, preferably in step c), the additional layer 300 is obtained by depositing a second particle composition having a weight content of at least 60% by weight, preferably at least 70% by weight, of the one or more carbides. The second particle composition is composed of a metal matrix, preferably an iron or aluminum base, for the remainder.

[0102] In particular, the second particle composition is identical to that used to define the base layer 30 according to method a).

[0103] Advantageously, in step c), the second particle composition can be deposited in the following manner.

[0104] - Thermal spray deposition technologies, such as HVOF (high-speed oxygen fuel) technology, HVAF (high-speed air fuel) technology, or APS (atmospheric plasma spraying) technology. Or,

[0105] - Cold spraying method, for example, the KM method (dynamic metallization method). Or,

[0106] - Deposition technologies using laser beams, such as LMD (Laser Metal Deposition), HSLC (High-Speed ​​Laser Cladding), EHLA (Ultra-High-Speed ​​Laser Plating), and TSC (Top-Speed ​​Cladding).

[0107] In particular, step c) can be carried out until the thickness of the additional layer 300 is 10 μm to 150 μm, preferably 30 μm to 120 μm.

[0108] Step b) is preferably carried out using at least one first laser beam. The output of this laser beam is in the range of 12 to 22 kW and is preferably a Gaussian, top-hat, or top-hat ring type.

[0109] In step b), the first particle composition is deposited using a single nozzle or two or more nozzles.

[0110] Preferably, in step b), the first particle composition is

[0111] - Total flow rate between 30g / min and 300g / min,

[0112] - Tangential velocity between 100 m / min and 250 m / min,

[0113] - Deposition rate is 1m 2 / h to 14m 2 It is deposited between / h.

[0114] Preferably, in step b), an additional laser beam having an output of 1 kW to 15 kW can be used before using the first laser beam. Preferably, the additional laser beam is Gaussian, top-hat, or top-hat ring type. Operationally, the additional laser beam pre-treats at least one of the brake surfaces 2a, 2b on which the first particle composition is intended to be deposited.

[0115] Advantageously, when using mode b), in step b), it is possible to use an additional laser beam with an output of 1 to 20 kW after using the first laser beam. Preferably, the additional laser beam is Gaussian, top-hat, or top-hat ring type. Operationally, the additional laser beam post-treats at least one of the braking surfaces (2a, 2b) on which the first particle composition has been pre-deposited in order to promote adhesion of the additional layer 300.

[0116] According to one embodiment, the formation of a metallurgical bond between a substrate and a layer deposited or welded on the substrate is performed using one or more laser beams, such as a bifocal laser.

[0117] As is clear from the above, the brake disc and method for manufacturing the same according to the present invention make it possible to overcome the shortcomings of the prior art.

[0118] Surprisingly, the brake disc 1 according to the present invention was found to possess both corrosion resistance and wear resistance, while simultaneously not exhibiting delamination or interlayer delamination (at least to a very low degree compared to coatings made of titanium or known alloys).

[0119] Therefore, the disk 1 according to the present invention guarantees sufficient thermal and mechanical performance and exhibits reliability over time.

[0120] While not necessarily bound by this theoretical explanation, the following hypothesis can be proposed in relation to the fact that delamination and interlaminar separation do not substantially occur.

[0121] - The intermediate fusion layer ensures an extremely stable and strong bond between the base layer 30 and the brake band. This is because it is a mutual penetration area between the two parts, and this mutual penetration resists the tension parallel to the brake surface that would otherwise cause delamination or detachment.

[0122] Similarly, because the growth direction of the crystal structure is mainly perpendicular to the braking surface, it blocks the propagation of cracks parallel to the braking surface, which can cause delamination and flaking.

[0123] Therefore, these two properties work synergistically to suppress peeling and delamination phenomena.

[0124] In particular, these two aspects ensure proper adhesion to the brake surface even under the thermal load during braking.

[0125] The corrosion resistance stems from the presence of titanium. Specifically, the use of titanium or its alloys guarantees the following:

[0126] - Corrosion resistance for several hundred hours in salt spray testing (SST)

[0127] - Excellent resistance to high-temperature corrosion

[0128] - Good mechanical ductility

[0129] The low wear resistance of titanium is compensated for by the presence of carbides dispersed in the titanium or titanium alloy matrix forming the base layer 30, or concentrated in the coating layer 300.

[0130] Using a titanium alloy instead of pure titanium improves resistance to thermal shock during braking, while also increasing hardness, resulting in advantages such as extended driving range and reduced dust emissions.

[0131] This invention makes it possible to manufacture brake discs that combine the corrosion resistance and wear resistance of titanium, and that exhibit virtually no peeling or delamination.

[0132] The brake disc for disc brakes based on this invention is easy to manufacture and inexpensive.

[0133] Finally, the method of the invention makes it possible to manufacture brake discs for disc brakes that are resistant to corrosion and wear, and less prone to delamination and interlayer delamination, in a manner that can be easily applied on an industrial scale.

Claims

1. A disc (1) for a disc brake, The disc (1) is equipped with a brake band (2), The brake band (2) has two opposing brake surfaces (2a, 2b), The brake band (2) is made of gray cast iron or steel. The disc (1) includes a base layer (30) that covers at least one of the two brake surfaces (2a, 2b) of the brake band (2), The base layer (30) consists of a titanium matrix and / or titanium alloy matrix containing one or more carbides, forming a tribologically active surface of the disk (1); or The base layer (30) consists of a layer of titanium and / or a titanium alloy, and is covered with a coating layer (300), the coating layer consists of a layer based on one or more carbides, and forms the tribologically active surface of the disk (1). The one or more carbides mentioned above are selected from the group consisting of titanium carbide (TiC), tungsten carbide (WC), chromium carbide, niobium carbide (NbC), molybdenum carbide (Mo2C), and silicon carbide (SiC). Between the base layer (30) and the brake band (2) made of gray cast iron or steel, there exists an intermediate mutually fused layer (32) having a mixed composition of the base layer (30) and the brake band (2). The aforementioned base layer (30) has a crystalline structure, The growth direction of the aforementioned crystal structure is generally perpendicular to the braking surface (2a, 2b) of the disc (1).

2. The base layer (30) is the result of a metallurgical bond formed between at least one of the braking surfaces (2a, 2b) and the first particle composition deposited on the braking surfaces (2a, 2b). The aforementioned deposition is carried out by a deposition technique using a laser beam, preferably by LMD (laser metal deposition) technique. The disk (1) according to claim 1, wherein the first particle composition has the same composition as the base layer (30).

3. The aforementioned titanium alloy contains aluminum, Preferably, the disc (1) according to claim 1 or 2, wherein the weight content of the aluminum is 2% or more.

4. The aforementioned titanium alloy further contains vanadium, Preferably, the disc (1) according to claim 3, wherein the weight content of vanadium is 1% or more.

5. The aforementioned titanium alloy is an alloy of titanium, aluminum, and vanadium. The aforementioned aluminum is present in a weight content of 2% to 8%, The vanadium is present in a weight content of 1% to 10%, The disc (1) according to any one of claims 1-4, wherein the remaining portion of the alloy is titanium.

6. The disk (1) according to any one of claims 1 to 5, wherein the thickness of the base layer (30) is between 5 μm and 700 μm, preferably between 50 μm and 400 μm.

7. The disk (1) according to any one of claims 1 to 6, wherein the base layer (30) is made of titanium or the titanium alloy.

8. The disk (1) according to any one of claims 1 to 6, wherein the base layer (30) is made of a titanium matrix or titanium alloy containing one or more carbides, and the weight content of the carbides is between 2% and 80%.

9. The disc (1) according to any one of claims 1 to 7, wherein the coating layer (300) contains at least 60% by weight, preferably at least 70% by weight, of one or more of the carbides.

10. The disk (1) according to claim 9, wherein the remaining portion of the coating layer (300) is composed of ...

11. The disk (1) according to any one of claims 1 to 7, wherein the coating layer (300) is entirely composed of one or more carbides.

12. The disk (1) according to any one of claims 1 to 11, wherein the coating layer (300) is obtained by thermal spraying technology such as HVOF (high-speed oxygen fuel) technology, HVAF (high-speed air fuel) technology, or APS (atmospheric plasma spray) technology.

13. The aforementioned coating layer (300) is obtained by cold spray deposition technology, for example, KM (kinetic metallization) technology, the disk (1) according to any one of claims 1 to 11.

14. The disk (1) according to any one of claims 1 to 11, wherein the coating layer (300) is obtained by a deposition technique using a laser beam, for example, LMD (laser metal deposition) technique, HSLC (high-speed laser cladding) technique, EHLA (ultrahigh-speed laser pladding) technique, or TSC (top-speed cladding) technique.

15. The disk (1) according to any one of claims 1 to 14, wherein the thickness of the coating layer (300) is between 10 μm and 150 μm, preferably between 30 μm and 120 μm, and more preferably between 50 μm and 90 μm.

16. A method for manufacturing a brake disc (1), Step a) prepare a brake disc (1) having a brake band (2) having two opposing brake surfaces (2a, 2b) and made of gray cast iron or steel, The process includes step b) depositing a first particle composition containing titanium or a titanium alloy onto at least one of the brake surfaces (2a, 2b) using a laser beam deposition technique, preferably LMD (laser metal deposition) technique, to form a base layer (30) covering at least one of the two opposing brake surfaces (2a, 2b) of the brake band (2), The manufacturing method includes forming a tribologically active coating layer containing one or more carbides on at least one brake surface. The first particle composition deposited in step b) includes one or more carbides, the first particle composition includes titanium, or a mixture of titanium and one or more titanium alloy metals, and the tribologically active coating layer is directly formed by the base layer (30); or In step c) following step b), an additional layer (300) based on one or more carbides is deposited on the base layer (30), wherein the first particle composition deposited in step b) consists of titanium or a mixture of titanium and one or more titanium alloy metals, and the tribologically active coating layer is composed of the additional layer (300). The one or more carbides mentioned above are titanium carbide (TiC), tungsten carbide (WC), chromium carbide, niobium carbide (NbC), and molybdenum carbide (Mo). ２ C) A method selected from the group consisting of silicon carbide (SiC).

17. The aforementioned titanium alloy contains aluminum, Preferably, the aluminum content is 2% or more by weight, according to the method of claim 16.

18. The aforementioned titanium alloy further contains vanadium, Preferably, the vanadium content is 1% or more by weight, according to the method of claim 17.

19. The aforementioned titanium alloy is an alloy of titanium, aluminum, and vanadium. The aforementioned aluminum is present in a weight content of 2% to 8%, The vanadium is present in a weight content of 1% to 10%, The method according to any one of claims 16-18, wherein the remaining portion of the alloy is titanium.

20. The method according to any one of claims 16-19, wherein step b) is carried out until the thickness of the base layer (30) is 5 μm to 700 μm, preferably 50 μm to 400 μm.

21. The method according to any one of claims 16-20, wherein the weight content of one or more carbides in the first particle composition is 2% to 80%.

22. In step c), the additional layer (300) is obtained by depositing the second particle composition. The method according to any one of claims 16-20, wherein the weight content of the one or more carbides in the second particle composition is at least 60% by weight, preferably at least 70% by weight.

23. The method according to claim 22, wherein the second particle composition consists of the remaining portion of ...

24. The method according to claim 22, wherein the second particle composition is composed entirely of one or more of the carbides.

25. In step c), the second particle composition is Thermal spray deposition techniques, such as HVOF (high-velocity oxygen fuel) technology, HVAF (high-velocity air fuel) technology, or APS (atmospheric plasma spraying) technology; or Cold spraying, for example, KM (kinetic metallization) technology; or The method according to any one of claims 22-24, wherein the material is deposited using a laser beam deposition technique, such as LMD (laser metal deposition), HSLC (high-speed laser cladding), EHLA (ultrahigh-speed laser pladding), or TSC (top-speed cladding).

26. The method according to any one of claims 22-25, wherein step c) is carried out until the thickness of the additional layer (300) is 10 μm to 150 μm, preferably 30 μm to 120 μm, and more preferably 50 μm to 90 μm.

27. Step b) is performed using at least one first laser beam, The output of the laser beam is between 12 kW and 22 kW. The method according to any one of claims 16-26, wherein the laser beam is preferably Gaussian, top-hat, or top-hat ring type.

28. In step b), the first particle composition is deposited using a single nozzle or two or more nozzles. The total flow rate is between 30 g / min and 300 g / min. When the tangential velocity is between 100 m / min and 250 m / min, Sedimentation rate 1m ２ / h to 14m ２ It is between / h. The method according to any one of claims 16-27.

29. In step b) above, prior to using the first laser beam, a further laser beam having an output of 1 to 15 kW is used. Preferably, the further laser beam is Gaussian, top-hat, or top-hat ring type. The method according to claim 27 or claim 28, which is dependent on claim 27, wherein the further laser beam pre-treats at least one of the braking surfaces (2a, 2B).

30. In step b) above, after using the first laser beam, use a further laser beam having an output of 1 to 20 kW. Preferably, the further laser beam is Gaussian, top-hat, or top-hat ring type. The method according to claim 27, or claim 28 or 29, which is dependent on claim 27, wherein the further laser beam performs post-treatment on at least one of the brake surfaces (2a, 2b) on which the first particle composition has been pre-deposited.

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